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Good Example Of Aquatic Life And Habitat Essay

Type of paper: Essay

Topic: Water , River , Environment , Species , Quality , Fish , Population , Abundance

Published: 01/22/2022

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The global economy of today is casting its effect on the earth’s capacity to maintain life’s abundance. What we see around is not promising, and it shows the need for reorientation. The focus is fast shifting on the relation between nature and the humans. The humans with their activities are destroying the very plant they live on. The aim is to look for the right ways to live on the life-giving planet, by having the right relationship. New understandings are fast emerging to understand the relationship between humans and nature. TAC or Thames Anglers’ Conservancy is a voluntary organization founded in 2010 with the objective of conservation of the River Thames. The members of the organization are well familiar with the river and have noticed how the river and its habitat has changed over time. Still, the river faces several challenges and population of eel have crashed. On the other hand, populations of invasive species like American Signal Crayfish and Chinese Mitten Crabs have damaged the ecology of the river. The potential impact of illegal fishing methods, poaching and Thames HydroPower projects need to be measured. TAC campaigns against sewage entering the Thames and how the untreated sewage is leading to a serious environmental problem. There are efforts to improve and increase the Mogden Sewage Treatment Works. TAC is getting stakeholders, conservation organizations, Environment Agency, river user groups, and local councils to come together in their efforts to make the Thames a safer environment. Together with Angling Trust, it fights pollution and poaching as well as other issues that are damaging the aquatic environment (Anglers dedicated to protecting and improving the River Thames 2016). The River Thames has been a high-profile project regarding improvements to the water quality and restoring Atlantic salmon. It has been observed that restoration of certain species of plants and animals is getting common around the world, and one good example is the Atlantic salmon. The efforts are seen as a response to the severe decline in the populations of salmon in rivers. The continued decline was attributed to environmental changes within rivers, happening because of exploitation of land and water resources by humans. Atlantic salmon not only holds a sporting and commercial value but remains a key indicator of the quality of water and ecosystem health as asserted by Griffiths et al. (2733). The data on fish abundance and their environmental conditions collected over a decade shows substantial variation in the abundance. The general pattern is a trend of deterioration over the years. One of the main reasons is rapid urbanization and industrialization of Greater London that has led to pollution. The results are a decline in fish and other biota as stated by Araújo, Williams, and Roland (305). It has bene observed that an improved effluent quality of the major Sewage Works led to an increase in fish population and species diversity. Seasonal variation influences the marked cycles of fish abundance in environmental conditions and the biological indicators of water quality (Araújo, Williams and Roland 306). The effect of pollution alters the diversity and the abundance of species as well as deteriorates fish habitat as reported by Araújo, Williams, and Roland (316). There are limitations to the recent attempts of genetically assigning Thames, salmon to northern populations. However, the results support that salmon caught in the Thames have strayed from other rivers. This indicates the need of making concerted efforts for improving river quality and habitat, rather than just focusing on long-term stocking of the endangered species (Griffiths et al. 2737). Again, it is the right balance of relation between the humans and the nature that can help restore ecosystem functioning and continuity, and not just focus on the immediate habitat of the species. This will encourage the populations of salmon to reestablish naturally. The above discussion shows how the relation between the human and nature can make the biotic environment change for the better or worse.

Works Cited

"Anglers dedicated to protecting and improving the River Thames." Thames Anglers' Conservancy. 2016. Web. 18 Oct. 2016. Araújo, Francisco Gerson, W. Peter Williams, and Roland G. Bailey. "Fish Assemblages as Indicators of Water Quality in the Middle Thames Estuary, England (1980-1989)." Estuaries 23.3 (2000): 305-17. Web. Griffiths, Andrew M., et al. "Restoration Versus Recolonisation: The Origin of Atlantic Salmon ( Salmo Salar L.) Currently in the River Thames." Biological Conservation 144.11 (2011): 2733-8. Web.

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The Ocean: Life Below Water and Why it Matters

Key questions >>>

• Why does the ocean matter? How is the ocean important for sustainable development?
• What does the sustainable blue economy offer us?
• What are the ocean knowledge gaps?
• How do we need to develop a multidisciplinary ocean science?

The ocean covers around three-quarters of the earth's surface and contains more than 90% of living species on our planet. The ocean is also the single largest ecosystem in the world, and it provides food for billions of people worldwide, as well as maritime transport, renewable energies, and other goods and services like regulating, cultural and supporting services. 

Nevertheless, the ocean is not indestructible, and our footprint is very large. Overfishing, toxic pollution, invasive species, nutrient over-enrichment, habitat degradation and destruction, biodiversity loss, dependence of a growing global population on its goods and services, and coastal development, all threaten the sustainability of coastal ocean ecosystems ( Vanderweerd in Sherman and McGovern, 2011). Ocean acidification is also a growing threat that may be more important than warming, pollution and overfishing (Roberts, 2011).

Why Does the Ocean Matter?

Oceans mean different things for different people: life, passion or wonderment; vastly important; a very important source of life and energy; an incredible source of food and amazing source of biodiversity; it's wild, exciting, terrifying and exhilarating; means a lot to me, if something happens I will not have the fun I’m used to; it's a livelihood, it's been there for generations and hopefully will be there for generations to come.’ (Adapted from video excerpt, Plymouth Marine Laboratory, 2011, in Muñoz-Sevilla and Le Bail 2017).

According to the World Wildlife Fund, the ocean is currently valued at $24 trillion dollars. The goods and services from marine environments add up to an additional $2.5 trillion yearly. This means the ocean would have the seventh-largest GDP in the world.  However, the value of the ocean relies on its current output, which in turn depends on its conditions. Climate change, ocean acidification, habitat destruction, pollution and overfishing are endangering the ocean and threatening its value and the security and livelihood of the three billion people who depend on it. Most of these people live in Small Island Developing States, they are among the ones who contribute least to these issues, but they are the ones at most risk, as they’re already vulnerable. ( Hoegh-Guldberg 2015)

Agenda 2030: SDG 13 and SDG 14

A historical change has been taking place for the past 23 years, from Agenda 21 to Agenda 2030. At the Rio de Janeiro Earth Summit in 1992, more than 178 countries adopted Agenda 21. The Millennium declaration was adopted after the 2000 Millennium Summit in New York. 10 years after the Rio Earth Summit, in the Millennium Development Goals (MDGs) that were adopted during the Earth Summit in Johannesburg, ocean issues were included in the conversation for the first time. 

In 2012, at the United Nations Conference on Sustainable Development (also popularly known as Rio+20), member states adopted the document titled “The Future We Want”, which set the process of developing the sustainable development goals (SDGs) building on the MDGs. Finally, during the UN Sustainable Development Summit in 2015, seventeen SDGs were adopted which are an integral part of the 2030 Agenda.  

Progress of SDG 14 in 2019

The expansion of protected areas for marine biodiversity and existing policies and treaties that encourage responsible use of ocean resources are still insufficient to combat the adverse effects of overfishing, growing ocean acidification and worsening coastal eutrophication. As billions of people depend on oceans for their livelihood and food source, increased efforts and interventions are needed to conserve and sustainably use ocean resources at all levels. 

• Ocean acidification is caused by the uptake of atmospheric CO 2 by the ocean, which changes the chemical composition of the seawater. Long-term observations over the past 30 years have shown an average increase of acidity of 26 percent since pre-industrial times. At this rate, an increase of 100 to 150 percent is predicted by the end of the century, with serious consequences for marine life. 
• To achieve sustainable development of fisheries, fish stocks must be maintained at a biologically sustainable level. Analysis reveals that the fraction of world marine fish stocks that are within biologically sustainable levels declined from 90 percent in 1974 to 66.9 percent in 2015. 
• As of December 2018, over 24 million km 2 (17.2 per cent) of waters under national jurisdiction (0–200 nautical miles from a national border) were covered by protected areas, a significant increase from 12 percent in 2015 and more than double the extent covered in 2010. The protected areas increased from 31.2 per cent in 2000 to 44.7 per cent in 2015 and to 45.7 per cent in 2018. 
• Illegal, unreported and unregulated fishing remains one of the greatest threats to sustainable fisheries, the livelihoods of those who depend upon them and marine ecosystems. Most countries have taken measures to combat such fishing and have adopted an increasing number of fisheries management instruments in the past decade. 
• Small-scale fisheries are present in almost all countries, accounting for more than half of total production on average, in terms of both quantity and value. To promote small-scale fishers’ access to productive resources, services and markets, most countries have developed targeted regulatory and institutional frameworks. However, more than 20 per cent of countries have a low to medium level of implementation of such frameworks, particularly in Oceania and Central and South Asia.

The Ocean Decade

To recognize that more needs to be done to mitigate the global decline in ocean health, in December 2017, the UN declared 2021 to 2030 as the decade of ‘Ocean Science and Sustainable Development’. 

The Ocean Decade will strengthen international cooperation in all levels by strengthening dialogues, developing partnerships, developing capacity-building and leveraging investment, while supporting the entire 2030 Agenda for sustainable development. Other critical goals include improving ocean literacy and education to modify social norms and behaviors, and creating new models for ocean action.

The Ocean Decade aims to include science-informed mitigation and adaptation policies around the world and share knowledge with coastal communities who are most vulnerable to the changes of the ocean. (Claudet et al. 2019)

The COVID-19 Pandemic and the Ocean 

From Little Blue Letter, Glen Wright

• Marine creatures are enjoying some quiet time as underwater noise levels drop. Scientists are studying these effects on marine mammals.
• ​From Florida to Thailand, the number of sea turtles nests has increased on the now-empty beaches. The rapid recovery of marine wildlife in coastal areas shows how extensive our impacts are and highlights the importance of protected areas. 
• Fishers around the world are struggling with decreased demand, lack of sanitary conditions and logistical challenges. In some countries, like India, food security of the communities may be affected by this disruption of supply chains.
• PADI and Rash’R are producing (non-profit)  reusable face masks made from Ocean plastic , with designs based on sea animals!

Final Remarks

We can all take small steps towards protecting our ocean. Reduction of single-use plastic, responsible fish consumption, avoiding ocean harming products, and making your voice heard can all directly contribute towards a healthier ocean. However, more indirect approaches can be taken by reducing the amount of greenhouse gases produced by our daily activities and, therefore, reducing our carbon footprint. Reducing red meat consumption, consuming locally sourced products and using personal vehicles less are all examples of small steps we can take towards reducing our impact. The sum of individual actions can truly make a difference in the fate of our ocean.

Collectively, we need to form a global ocean community, acknowledging that all of our actions have an impact on the ocean (Claudet et al. 2019). And, although it is incumbent on each of us to take steps to protect the ocean, collective action is also required. New models for ocean action, which are collaborative, intergenerational, cross-cultural, and multi-sectoral, are needed in the coming decade, in order to protect our beloved ocean. 

The ocean is our life support system, it connects every one of us, you can think of the ocean as the blue heart  of this planet, but then we look after that heart and we know how we are damaging it and it needs intensive care. We know that scientists, politicians and stakeholders are talking to each other, but it isn’t just up to them, each and every one of us can make the difference, even if the difference might be small, after all individual small drops of sea water can make up the vast ocean . (Adapted from video excerpt, Plymouth Marine Laboratory 2011, in Muñoz-Sevilla and Le Bail 2017).

Bibliography

Cheung, W. et al (2013), “Signature of Ocean Warming in Global Fisheries Catch”, Nature, 497(2013): 365–368.

Claudet, J. et al (2019), “A Roadmap for Using the UN Decade of Ocean Science for Sustainable Development in Support of Science, Policy, and Action”, One Earth , 2(1): 34-42.

Halpern, B. et al (2012), “An Index to Assess the Health and Benefits of the Global Ocean, Nature , 488(2012): 615–620.

UNESCO and UNEP (United Nations Educational, Scientific and Cultural Organization and United Nations Environment Programme) (2016), Large Marine Ecosystems: Status and Trends, Summary for Policy Makers , Nairobi: UNEP.

Muñoz-Sevilla N. and M. Le Bail M (2017), “Latin American and Caribbean Regional Perspectives on Ecosystem Based Management (EBM) of Large Marine Ecosystems Goods and Services”, Environmental Development , 22(2017), 9-17.

Munoz-Sevilla N. et al (2019), UNU Ocean Institute Scoping Study Report , Tokyo: United Nations University.

Plymouth Marine Laboratory (2011), Ocean Acidification: Connecting Science, Industry, Policy and Public (A Short Film for the Natural Environment Research Council and the UK Ocean Acidification Research Programme), Plymouth Marine Laboratory

Roberts D. (2011), In: Ocean Acidification: Connecting Science, Industry, Policy and Public . A short film for the Natural Environment Research Council and the UK Ocean Acidification Research Programme. Plymouth Marine Laboratory.

Sherman, K. and G. McGovern (2011), Toward Recovery and Sustainability of the World’s Large Marine Ecosystems during Climate Change , Gland, Switzerland: International Union for Conservation of Nature.

Sherman K. et al (2017), “Sustainable Development of Latin American and the Caribbean Large Marine Ecosystems”, Environmental Development , 22(2017), 1-8.

United Nations (2015), Transforming Our World: the 2030 Agenda for Sustainable Development , New York: UN.

Wright G. (2020), “The Pandemic and the Ocean”, Email Correspondence on May 1, 2020.

Hoegh-Guldberg, O. (2015), Reviving the Ocean Economy: The Case for Action , Geneva: World Wide Fund for Nature.

Consulted on April 24th, 2020. (2019) What is the United Nations Decade of Ocean Science for Sustainable Development?. https://www.oceandecade.org/about?tab=our-story . Consulted on May 4th, 2020.

Introductory essay

Written by the educators who created The Deep Ocean, a brief look at the key facts, tough questions and big ideas in their field. Begin this TED Study with a fascinating read that gives context and clarity to the material.

How inappropriate to call this planet Earth when it is quite clearly Ocean. Arthur C. Clarke

Planet Ocean

In the late 1960s, the Apollo Mission captured images of Earth from space for the very first time. These iconic photos gave people around the world a fresh perspective on our home planet — more specifically, its vast and dazzling expanses of blue. It's perhaps unsurprising that science has subsequently established the key roles that the ocean and its marine organisms play in maintaining a planetary environment suitable for life.

While the Apollo astronauts were sending back pictures of our blue planet, a scientist at the Jet Propulsion Laboratory in California was searching for ways to detect life on other planets such as Mars. James Lovelock's investigations led him to conclude that the only way to explain the atmospheric composition of Earth was that life was manipulating it on a daily basis. In various publications, including his seminal 1979 book Gaia: A New Look at Life on Earth , Lovelock launched the Gaia hypothesis, which describes how the physical and living components of the natural environment, including humankind, interact to maintain conditions on Earth. During the same period, marine scientists including Lawrence Pomeroy, Farooq Azam and Hugh Ducklow were establishing a firm link between the major biogeochemical cycles in the oceans and marine food webs, particularly their microbial components. In the late 1980s and 1990s, large-scale research programs like the Joint Global Ocean Flux Study (JGOFS) explored ocean biogeochemistry and established the oceans' pivotal role in the Earth's carbon cycle.

Research efforts like these underscored the oceans' critical importance in regulating all the major nutrient cycles on Earth. It's now widely recognized that the ocean regulates the temperature of Earth, controls its weather, provides us with oxygen, food and building materials, and even recycles our waste.

The advent of deep-sea science

It seems remarkable that until fairly recently many scientists believed that life was absent in the deep sea. Dredging in the Aegean Sea in the 1840s, marine biologist Edward Forbes found that the abundance of animals declined precipitously with depth. By extrapolation he concluded that the ocean would be azoic (devoid of animal life) below 300 fathoms (~550m depth). Despite evidence to the contrary, scientists supported the azoic hypothesis, reasoning that conditions were so hostile in the deep ocean that life simply could not survive. Extreme pressure, the absence of light and the lack of food were viewed as forming an impenetrable barrier to the survival of deep-sea marine species.

But others were already proving this hypothesis wrong. As Edward Forbes published his results from the Aegean, Captain James Clark Ross and the famous naturalist John Dalton Hooker were exploring the Antarctic in the Royal Navy vessels HMS Terror and HMS Erebus . During this expedition, Ross and Hooker retrieved organisms from sounding leads at depths of up to 1.8km, including urchin spines and other fragments of various marine invertebrates, a number of bryozoans and corals. Ross remarked, "I have no doubt that from however great a depth we may be enabled to bring up the mud and stones of the bed of the ocean we shall find them teeming with animal life." This contention was supported by work of Norwegian marine biologists Michael Sars and George Ossian Sars who dredged hundreds of species from depths of 200 to 300 fathoms off the Norwegian coast.

Further evidence came from natural scientists William Carpenter and Charles Wyville-Thomson, who mounted expeditions in 1868 and 1869 on the vessels HMS Lightening and HMS Porcupine to sample the deep ocean off the British Isles, Spain and the Mediterranean. The findings of these expeditions, which Wyville-Thomson published in his 1873 book The Depths of the Sea , confirmed the existence of animal life to depths of 650 fathoms — including all the marine invertebrate groups — and suggested that oceanic circulation exists in the deep sea.

This convinced the Royal Society of London and the Royal Navy to organize the circumnavigating voyage of HMS Challenger in the 1870s. In part, the expedition's purpose was to survey potential routes for submarine telegraph cables, and so the links between scientific exploration and human use of the deep sea were established in the very early days of oceanography. The Challenger expedition was a watershed for deep-ocean science, establishing the basic patterns of distribution of deep-sea animals, and that their main food source was the rain of organic material from surface waters.

In the 1950s, the Danish Expedition Foundation's Galathea voyage established that life occurred at depths of more than 10km in the Philippines Trench. In 1960 marine explorers Auguste Picard and Don Walsh reached the bottom of the Challenger Deep in the Marianas Trench, at a depth estimated to be 10,916 meters--the deepest part of the ocean — where they observed flatfish from the porthole of their pressure sphere. This feat was not repeated until 2012 when James Cameron visited the bottom of the Challenger Deep in the submersible Deepsea Challenger .

Hype or hyper-diversity in the deep sea?

While working at Woods Hole Oceanographic Institution in the late 1960s, scientists Howard Sanders and Robert Hessler developed new types of deep-sea trawls called epibenthic sleds that featured extra- fine mesh in the nets. When the new trawls were tested, they recovered an astonishing diversity of species from the deep sea. It became apparent that the species richness of deep-sea communities actually increased with greater depth to a peak somewhere on the continental slope between 2,000 and 4,000 meters depth. Beyond these depths, diversity appeared to decrease (but not everywhere), or the pattern was unclear.

How to explain this amazing diversity in the deep sea? Initially, scientists credited the species richness to the stability of environmental conditions in the deep ocean, which would support extreme specialization of the animals and thus allow many species to coexist. This is known as the stability-time hypothesis. Some scientists considered that small-scale variations of the sediments of the deep ocean, including reworking of seabed by animals, was important in maintaining microhabitats for many species. In the late 1970s other scientists suggested that conditions in shallow waters allow competitive exclusion, where relatively few species dominate the ecosystem, whereas in deeper waters environmental factors associated with depth and a reduced food supply promote biological communities with more diversity.

Fred Grassle and Nancy Maciolek added substantially to our knowledge of deep-sea biodiversity when they published a study of the continental slope of the eastern coast of the USA in the early 1990s. Grassle and Maciolek based their study on quantitative samples of deep-sea sediments taken with box cores. These contraptions retrieve a neat cube-shaped chunk of the seabed and bring it to the surface enclosed in a steel box. Scientists then sieve the mud and count and identify the tiny animals living in the sediment.

In a heroic effort, Grassle and Maciolek analyzed 233 box cores, an equivalent of 21 square meters of the seabed, identifying 90,677 specimens and 798 species. They estimated that they found approximately 100 species per 100 km along the seabed they sampled. Extrapolations of this figure suggested that there may be 1 - 10 million macrofaunal species in the deep sea.

What's more, some scientists argued that Grassle and Maciolek's estimates represented only a small part of the species diversity in the ocean depths. Dr John Lambshead of London's Natural History Museum pointed out that Grassle and Maciolek had not examined the smallest animals in sediments — the meiofauna — made up of tiny nematode worms, copepods and other animals. These are at least an order of magnitude more diverse than the macrofauna, suggesting that as many as 100 million species may inhabit the deep ocean.

However, given that the latest approximation of the Earth's biodiversity is 10 million species in total, Lambshead's number appears to be an overestimate. Scientists have since realized that there are major problems with estimating the species richness of large areas of the deep sea based on local samples. Today we understand that species diversity in the deep ocean is high, but we still don't know how many species live in the sediments of the continental slope and abyssal plains. We also don't understand the patterns of their horizontal distribution or the reasons for the parabolic pattern of species diversity as it relates to depth. Evidence suggests, however, that the functioning of deep-sea ecosystems depends on a high diversity of animals — although exactly why remains open to conjecture.

The creation of deep-sea environments: "Drifters" and "Fixists"

In 1912, German scientist Alfred Wegener put forward his theory of continental drift to address many questions that engaged the geologists and biologists of his time. For example, why do the continents appear to fit together as though they had once been joined? Why are many of the large mountain ranges coastal? And, perhaps most intriguing, why do the rocks and fossil biotas (combined plant and animal life) on disconnected land masses appear to be so similar?

Wegener's theory provoked a major scientific controversy that raged for more than 50 years between "drifters" and "fixists." Critics of Wegener's — the "fixists" — pointed out that Wegener's proposed mechanism for drift was flawed.

In the search for an alternate mechanism to explain continental drift, British geologist Arthur Holmes suggested that radioactive elements in the Earth were generating heat and causing convection currents that made the Earth's mantle fluid. Holmes argued that the mantle would then rise up under the continents and split them apart, generating ocean basins and carrying the landmasses along on the horizontally-moving currents.

Following World War II, scientific expeditions employing deep-sea cameras, continuously recording echo-sounders, deep-seismic profilers and magnetometers lent support to the arguments of Holmes and his fellow "drifters." Scientists realized that the deep sea hosted a vast network of mid-ocean ridges located roughly in the center of the ocean basins. These ridges were characterized by fresh pillow lavas, sparse sediment cover, intense seismic activity and anomalously high heat flow. Scientists found geologically-synchronous magnetic reversals in the rocks of the ocean crust moving away from either side of the mid-ocean ridges. Added to this was the fact that nowhere could scientists find sediments older than the Cretaceous in age. Together, these findings suggested that new oceanic crust was being formed along the mid-ocean ridges, while old oceanic plates are forced underneath continental plates and destroyed along the ocean trenches. By the late 1960s, the bitter scientific debate between the "fixists" and the "drifters" was finally settled.

Life without the sun

During the next decade, scientists investigating volcanic activity at mid-ocean ridges became interested in the associated phenomenon of hot springs in the deep sea. Anomalously high temperature readings over mid-ocean ridge axes led scientists to mount an expedition in 1977 to the 2.5 km-deep Galápagos Rift. From the submersible Alvin, the scientists observed plumes of warm water rising from within the pillow lavas on the seabed. Living amongst the pillows were dense communities of large vesicoyid clams, mussels, limpets and giant vestimentiferan tube worms (Siboglinidae). An abundance of bacteria around the Galápagos Rift site immediately suggested that these communities might be based on bacterial chemosynthesis, or chemolithotrophy, using chemical energy obtained by oxidizing hydrogen sulphide to drive carbon fixation. Subsequent investigation confirmed that the giant tube worms, clams and mussels actually hosted symbiotic sulphur-oxidizing bacteria in their tissues.

The discovery caused huge excitement in the scientific community. Here was life thriving in the deep sea, where primary production — the basis of the food web — was independent from the sun's energy. Furthermore, as scientists discovered additional vent communities and surveyed elsewhere in the mid-ocean ridge system, they found that environmental conditions were extreme, with high temperatures, acidic waters, hypoxia (lack of oxygen) and the presence of toxic chemicals the norm.

The implications of this were enormous and went well beyond the study of the ocean itself. First, it meant that life could exist elsewhere in our solar system in environments previously thought too extreme. Second, it widened the potential area for habitable planets around suns elsewhere in the universe. For example, the discovery in 2000 of the Lost City alkaline hydrothermal vents presented an environment that some scientists suggest is analogous to the conditions in which life evolved on Earth.

Subsequently, chemosynthesis has been discovered in many places in the ocean, including deep-sea hydrocarbon seeps, in large falls of organic matter such as whale carcasses, and from shallow-water sediments associated with, for example, seagrass beds.

Drawing down the oceans' natural capital

Over the past two decades, we've developed a much deeper understanding of the relationship between humankind and the natural world, including the Earth's oceans. In 1997 Robert Costanza and his colleagues published a paper in Nature that estimated the economic value of the goods and services provided by global ecosystems. Costanza and his colleagues argued that the living resources of Earth could be viewed as a form of natural capital with a value averaging $33 trillion per annum, upon which the entire human economy depended. These goods and services were later grouped into supporting (e.g. primary production), provisioning (e.g. food), regulating (climate regulation) and cultural (e.g. education) services.

While this knowledge may have been intuitive for many people, Costanza's recasting of the environment in economic terms forced policymakers, industry leaders and others to recognize the importance of long-term environmental sustainability. With the support of international agencies such as the World Bank, many countries are now implementing natural capital accounting procedures through legislation. The purpose of this is to help monitor and regulate the use and degradation of the environment and to ensure that the critical ecosystem goods and services underpinning economic activity and human well-being are not undermined.

Although it seems like a modern preoccupation, sustainability is actually a centuries-old challenge, particularly as it relates to marine environments. For example, there is evidence that aboriginal fisheries in ancient times may have overexploited marine species. Certainly by medieval times in Europe, a thriving market for fish, coupled with other developments like changing agricultural practices, forced species such as salmon and sturgeon into decline.

The Industrial Revolution led to an increase in hunting fish, seals and whales, thanks to the development of steam- and then oil-powered fishing vessels that employed increasingly sophisticated means of catching animals. Pelagic whaling began in the early 20th century; the development of explosive harpoons, the ability to process whales at sea, and the strong demand for margarine made from whale oil all contributed to dramatic rises in catches. Despite the initiation of the International Whaling Commission in 1946, a serial depletion of whale populations took place from the largest, most valuable species (e.g. blue whale) through to the smallest species (minke whale). The failure to regulate catches of whales led to the establishment of a near-moratorium on whaling in 1986.

Over the same post-war period, fishing fleets underwent a major expansion and deployed increasingly powerful fishing vessels. Improved technologies for navigating, finding fish and catching them led to increasing pressure on fish stocks and the marine ecosystems in which they lived. In 1998, after analyzing catch statistics from the United Nations Food and Agricultural Organisation (FAO), Daniel Pauly and his colleagues from the University of British Columbia identified a global shift in fish catches from long-lived, high trophic level predators to short-lived, low trophic level invertebrates and plankton-eating fish. This was the first evidence that fishing was having a global impact on marine ecosystems, causing major changes in the structure of ocean food webs. Aside from the economic impacts of "fishing down the food web," evidence was accumulating that it also affected the vulnerability and/or resilience of marine ecosystems to shocks such as invasions by alien species and climate-change effects such as mass coral bleaching.

Further evidence came in 2003 from a study by Ransom Myers and Boris Worm. Myers and Worm documented a significant decline over time in the stocks of certain large, predatory fish after analyzing information from research trawl surveys and the catches of the Japanese long-line fleet. Other studies over the same time period suggested that sharks, seabirds and turtles were suffering large-scale declines as they became by-catch in many industrial fisheries. Scientists also asserted that some fishing technologies, such as bottom trawling, were extremely damaging to seabed communities — deep-sea ecosystems in particular — by documenting the devastation of cold-water coral communities.

These studies sparked a bitter war of words between marine ecologists, fishing industry executives and fisheries biologists. While it has now been demonstrated that fish stocks can recover if levels of exploitation by fisheries are reduced through management measures, it's clear that in many parts of the world's oceans this is not happening. Overall, global yields from marine capture fisheries are in a downward trajectory. By-catch of some marine predators, such as albatrosses, still poses a threat of extinction. Habitat destruction resulting from fishing is continuing.

In addition to overfishing, other human activities are damaging marine ecosystems. During the 1960s and 1970s, several major accidents with oil tankers and oil installations resulted in serious oil spills. While oil pollution is still a significant problem, as illustrated by the Deepwater Horizon disaster in the Gulf of Mexico in 2010, other less-visible sources of pollution are causing large-scale degradation of the ocean.

Persistent organic pollutants and heavy metals such as mercury are being recognized as major health issues for marine animals (especially high trophic level predators, such as killer whales and tuna) and also for humans. The oceans are becoming the dumping ground for a wide range of chemicals from our personal care products and pharmaceuticals, as well as those that leach out of all manner of plastics that are floating in our seas. Agrochemicals are pouring into the oceans through rivers; in some cases these artificially fertilize coastal waters, generating blooms of algae which are broken down by bacteria, thus stripping the water of oxygen and creating dead zones.

Our release of greenhouse gases into the atmosphere, particularly carbon dioxide (CO2), is leading to a profound disturbance in ocean temperatures and ocean chemistry. Since the late 1970s, mass coral bleaching from ocean warming has killed large areas of tropical coral reefs. Marine animals are changing their distribution and the timing of their lifecycles, sometimes with catastrophic effects across the wider ecosystem. Such effects are often propagated from lower levels of food webs up through to predators such as fish and seabirds: witness recent declines in spectacled sea duck populations in the Arctic and the decline of cod populations in the North Sea. The oceans are becoming more acidic, which affects the growth rates of animals with calcium carbonate shells or skeletons and has other negative impacts on animal physiology. Many of these different stresses on marine species interact in a form of "negative synergy", inducing more severe effects than if they had presented in isolation. At the ecosystem level these stresses reduce the resilience of marine ecosystems to "shocks" arising from large-scale effects, such as anomalous warming events associated with climate change.

Ocean future

The TEDTalks in The Deep Ocean illuminate many current topics in marine science and oceanic exploration. These include the call for better conservation management in the face of unprecedented threats to marine ecosystems, the discovery and application of as-yet-untapped natural resources from the ocean depths, and the quest for improved technologies to support both of these endeavors. As Sylvia Earle eloquently reminds us in her 2009 TEDTalk, the oceans are critically important to maintaining the planet in a condition that is habitable, and better cooperative, international management of marine ecosystems is essential. However, as other TED speakers like Robert Ballard and Craig Venter argue, the oceans should also interest us because they contain vast untapped resources: unexploited mineral resources as well as genes, proteins and other biomolecules of marine life, which may furnish the medicines and industrial materials of the future.

Smart management of these natural resources requires knowledge, as do our efforts to ensure the oceans' ongoing species richness and their critical function in maintaining the Earth system. In their TEDTalks, explorers and scientists Edith Widder, Mike deGruy and Craig Venter share some of the amazing physical and biological features of ocean habitats and describe how new technologies allow more careful study and exploitation of deep-sea environments.

Despite these advances, there are still enormous gaps in our knowledge. In a TEDTalk he gave in 2008, Robert Ballard noted that many parts of the ocean remain entirely unexplored and he advocated for increased resources for organizations like NOAA. As many of the TED speakers in The Deep Ocean argue, marine science is more important than ever because the oceans are under serious threat from a range of human impacts including global-scale climate change.

However, these speakers also offer a message of hope, underscoring that there is still time to alter the current trajectory of degradation. Scientists including TED speaker John Delaney present a vision for the future where ecosystem-based management, coupled with the advent of new technologies that allow us to monitor ocean health in real time, provide us with tools to heal marine ecosystems. This may allow us to restore their capacity to provide goods and services for humankind over the long term. Measures such as marine-protected areas can maintain the oceans' important biogeochemical functions, but will also conserve the remarkable and beautiful marine ecosystems that have culturally enriched the human experience for millennia.

We'll begin our journey into The Deep Ocean with legendary explorer and oceanographer Sylvia Earle, who shares disturbing data about the decline of marine ecosystems and proposes one method to protect what she calls "the blue heart of the planet."

Sylvia Earle

My wish: protect our oceans, relevant talks.

Mike deGruy

Hooked by an octopus.

David Gallo

Underwater astonishments.

Edith Widder

Glowing life in an underwater world.

Robert Ballard

The astonishing hidden world of the deep ocean.

Craig Venter

On the verge of creating synthetic life.

John Delaney

Wiring an interactive ocean.

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Marine life

Our ocean, coasts, and estuaries are home to diverse living things. These organisms take many forms, from the tiniest single-celled plankton to the largest animal on Earth, the blue whale. Understanding the life cycles, habits, habitats, and inter-relationships of marine life contributes to our understanding of the planet as a whole. Human influences and reliance on these species, as well as changing environmental conditions, will determine the future health of these marine inhabitants. Toxic spills , oxygen-depleted dead zones, marine debris , increasing ocean temperatures, overfishing, and shoreline development are daily threats to marine life. Part of NOAA's mission is to help protect these organisms and their habitats.

Food webs describe who eats whom in an ecological community. Made of interconnected food chains, food webs help us understand how changes to ecosystems — say, removing a top predator or adding nutrients — affect many different species, both directly and indirectly.

Phytoplankton and algae form the bases of aquatic food webs. They are eaten by primary consumers like zooplankton, small fish, and crustaceans. Primary consumers are in turn eaten by fish, small sharks, corals, and baleen whales. Top ocean predators include large sharks, billfish, dolphins, toothed whales, and large seals. Humans consume aquatic life from every section of this food web.

Coral reefs are some of the most diverse ecosystems in the world. Coral polyps , the animals primarily responsible for building reefs, can take many forms: large reef building colonies, graceful flowing fans, and even small, solitary organisms. Thousands of species of corals have been discovered; some live in warm, shallow, tropical seas and others in the cold, dark depths of the ocean.

Seafood plays an essential role in feeding the world’s growing population. Healthy fish populations lead to healthy oceans and it's our responsibility to be a part of the solution. The resilience of our marine ecosystems and coastal communities depend on sustainable fisheries.

Estuaries are areas of water and shoreline where rivers meet the ocean or another large body of water, such as one of the Great Lakes. Organisms that live in estuaries must be adapted to these dynamic environments, where there are variations in water chemistry including salinity, as well as physical changes like the rise and fall of tides. Despite these challenges, estuaries are also very productive ecosystems. They receive nutrients from both bodies of water and can support a variety of life. Because of their access to food, water, and shipping routes, people often live near estuaries and can impact the health of the ecosystem.

Marine mammals are found in marine ecosystems around the globe. They are a diverse group of mammals with unique physical adaptations that allow them to thrive in the marine environment with extreme temperatures, depths, pressure, and darkness. Marine mammals are classified into four different taxonomic groups: cetaceans (whales, dolphins, and porpoises), pinnipeds (seals, sea lions, and walruses), sirenians (manatees and dugongs), and marine fissipeds (polar bears and sea otters).

Sea turtles breathe air, like all reptiles, and have streamlined bodies with large flippers. They are well adapted to life in the ocean and inhabit tropical and subtropical ocean waters around the world. Of the seven species of sea turtles, six are found in U.S. waters; these include the green, hawksbill, Kemp's ridley, leatherback, loggerhead, and olive ridley.

10 Easy Ways to Help Protect Marine Life

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The ocean is downstream of everything, so all of our actions, no matter where we live, affect the ocean and the marine life it holds. Those who live right on the coastline will have the most direct impact on the ocean, but even if you live far inland, there are many things you can do that will help marine life.

Eat Eco-Friendly Fish

Our food choices have a significant impact on the environment—from the actual items we eat to the way they are harvested, processed, and shipped. Going vegan is better for the environment, but you can take small steps in the right direction by eating eco-friendly fish and eating locally as much as possible. If you eat seafood, eat fish that is harvested sustainably, which means eating species that have a healthy population, and whose harvest minimizes bycatch and impacts on the environment.

Limit Your Use of Plastics, Disposables and Single-Use Projects

Have you heard of the Great Pacific Garbage Patch ? That is a name coined to describe the vast amounts of plastic bits and other marine debris floating in the North Pacific Subtropical Gyre, one of five major ocean gyres in the world. Sadly, all the gyres seem to have their garbage patch.

Plastic stays around for hundreds of years can be a hazard to wildlife and leaches toxins into the environment. Stop using so much plastic. Buy things with less packaging, don't use disposable items and use reusable bags instead of plastic ones wherever possible.

Stop the Problem of Ocean Acidification

Global warming has been a hot topic in the ocean world, and it is because of ocean acidification , known as 'the other global warming problem.' As the acidity of the oceans increases, it will have devastating impacts on marine life, including plankton , corals and shellfish, and the animals that eat them.

But you can do something about this problem right now. Reduce global warming by taking simple steps that will likely save money in the long run: drive less, walk more, use less electricity and water—you know the drill. Lessening your "​carbon footprint" will help marine life miles from your home. The idea of an acidic ocean is scary, but we can bring the oceans to a more healthy state with some easy changes in our behavior.

Be Energy-Efficient

Along with the tip above, reduce your energy consumption and carbon output wherever possible. This includes simple things like turning off the lights or TV when you're not in a room and driving in a way that increases your fuel efficiency. As Amy, an 11-year old reader said, "It might sound strange, but being energy efficient helps the Arctic marine mammals and fish because the less energy you use, the less our climate heats up—then the ice won't melt."

Participate in a Cleanup

Trash in the environment can be hazardous to marine life, and people too! Help clean up a local beach, park or roadway and pick up that litter before it gets into the marine environment. Even trash hundreds of miles from the ocean can eventually float or blow into the ocean. The  International Coastal Cleanup  is one way to get involved. That is a cleanup that occurs each September. You can also contact your local coastal zone management office or department of environmental protection to see if they organize any cleanups.

Never Release Balloons

Balloons may look pretty when you release them, but they are a danger to wildlife such as sea turtles, who can swallow them accidentally, mistake them for food, or get tangled up in their strings. After your party, pop the balloons and throw them in the trash instead of releasing them.

Dispose of Fishing Line Responsibly

Monofilament fishing line takes about 600 years to degrade. If left in the ocean, it can provide an entangling web that threatens whales, pinnipeds and fish (including the fish people like to catch and eat). Never discard your fishing line into the water. Dispose of it responsibly by ​ recycling it if you can, or into the garbage.

View Marine Life Responsibly

If you're going to be viewing marine life, take steps to do so responsibly. Watch marine life from the shore by going tide pooling . Take steps to plan a whale watching, diving trip or other excursions with a responsible operator. Think twice about "swim with dolphins " programs, which may not be suitable for dolphins and could even be harmful to people.

Volunteer or Work With Marine Life

Maybe you work with marine life already or are studying to become a marine biologist . Even if working with marine life isn't your career path, you can volunteer. If you live near the coast, volunteer opportunities may be easy to find. If not, you can volunteer on field expeditions such as those offered by Earthwatch as Debbie, our guide to ​ insects , has done, where she learned about sea turtles , wetlands, and giant clams!

Buy Ocean-Friendly Gifts

Give a gift that will help marine life. Memberships and honorary donations to non-profit organizations that protect marine life can be a great gift. How about a basket of environmentally-friendly bath or cleaning products, or a gift certificate for a whale watch or snorkeling trip? And when you wrap your gift - be creative and use something that can be re-used, like a beach towel, dish towel, basket or gift bag.

How Do You Protect Marine Life? Share Your Tips!

Are there things you do to protect marine life, either from your home or while visiting the coast, on a boat, or out volunteering? Please share your tips and opinions with others who appreciate marine life.

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Home — Essay Samples — Environment — Marine Life — How Aquatic Life Has Been Impacted By Pollution

How Aquatic Life Has Been Impacted by Pollution

• Categories: Marine Life

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Published: Mar 14, 2019

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Impacts of ocean acidification on marine organisms: quantifying sensitivities and interaction with warming

Kristy j kroeker.

* Bodega Bay Laboratory, University of California, 2099 Westside Rd, Bodega Bay, CA, 94923, USA

Rebecca L Kordas

† University of British Columbia, Vancouver, BC, Canada, V6T1Z4

‡ Puget Sound Restoration Fund, 590 Madison Ave N, Bainbridge Island, WA, 98110, USA

Iris E Hendriks

§ Global Change department, IMEDEA (CSIC-UIB), Instituto Mediterráneo de Estudios Avanzados, C/Miquel Marqués 21, Esporles (Mallorca), 07190, Spain

Laura Ramajo

¶ Laboratorio de Ecologia y Cambio Climatico, Facultad de Ciencias Universidad Santo Tomas, C/Ejercito, 146, Santiago de Chile

Gerald S Singh

Carlos m duarte.

‖ The UWA Oceans Institute and School of Plant Biology, University of Western Australia, 35 Stirling Highway, Crawley, 6009, Australia

Jean-Pierre Gattuso

** Laboratoire d'Océanographie de Villefranche-sur-Mer, CNRS-INSU, BP 28, Villefranche-sur-Mer Cedex, 06234, France

†† Université Pierre et Marie Curie-Paris 6, Observatoire Océanologique de Villefranche, Villefranche-sur-Mer Cedex, 06230, France

Associated Data

Ocean acidification represents a threat to marine species worldwide, and forecasting the ecological impacts of acidification is a high priority for science, management, and policy. As research on the topic expands at an exponential rate, a comprehensive understanding of the variability in organisms' responses and corresponding levels of certainty is necessary to forecast the ecological effects. Here, we perform the most comprehensive meta-analysis to date by synthesizing the results of 228 studies examining biological responses to ocean acidification. The results reveal decreased survival, calcification, growth, development and abundance in response to acidification when the broad range of marine organisms is pooled together. However, the magnitude of these responses varies among taxonomic groups, suggesting there is some predictable trait-based variation in sensitivity, despite the investigation of approximately 100 new species in recent research. The results also reveal an enhanced sensitivity of mollusk larvae, but suggest that an enhanced sensitivity of early life history stages is not universal across all taxonomic groups. In addition, the variability in species' responses is enhanced when they are exposed to acidification in multi-species assemblages, suggesting that it is important to consider indirect effects and exercise caution when forecasting abundance patterns from single-species laboratory experiments. Furthermore, the results suggest that other factors, such as nutritional status or source population, could cause substantial variation in organisms' responses. Last, the results highlight a trend towards enhanced sensitivity to acidification when taxa are concurrently exposed to elevated seawater temperature.

Introduction

Ocean acidification is projected to impact all areas of the ocean, from the deep sea to coastal estuaries ( Orr et al ., 2005 ; Feely et al ., 2009 , 2010 ), with potentially wide-ranging impacts on marine life ( Doney et al ., 2009 ). There is an intense interest in understanding how the projected changes in carbonate chemistry will affect marine species, communities, and ecosystems ( Logan, 2010 ; Gattuso & Hansson, 2011a ). The rapidly growing body of experimental research on the biological impacts of acidification spans a broad diversity of marine organisms and reveals an even broader range of species' responses, from reduced calcification rates in oysters (e.g., Gazeau et al ., 2007 ; Talmage & Gobler, 2010 ; Waldbusser et al ., 2011 ) to impaired homing ability in reef fishes ( Munday et al ., 2009 , 2010 ) to increased growth rates in macro algae ( Hurd et al ., 2009 ; Koch et al ., 2013 ). Translating the wide range of responses to ecosystem consequences, management actions, and policy decisions requires a synthetic understanding of the sources of variability in species responses to acidification and the corresponding levels of certainty of the impacts.

Meta-analysis is a quantitative technique for summarizing the results of primary research studies. It provides a transparent method to identify key patterns across numerous studies, and can be used to develop hypotheses for future research. Furthermore, it can be a powerful tool for placing individual studies into the context of a broader field of research on a topic. While several meta-analyzes have been published regarding ocean acidification ( Dupont et al ., 2010 ; Hendriks et al ., 2010 ; Kroeker et al ., 2010 ; Liu et al ., 2010 ), research on this topic is growing exponentially ( Gattuso & Hansson, 2011b ). Over 403 studies investigating ocean acidification have been published since the beginning of 2010, which more than triples the number of studies included in any previous meta-analysis of its impacts ( Hendriks et al ., 2010 ; Kroeker et al ., 2010 ; Liu et al ., 2010 ). These new studies provide an important opportunity to expand our understanding of species vulnerability and resilience to ocean acidification by including a broader array of species in the analyzes, as well as an opportunity to test the robustness of the patterns found in previous analyzes and highlight new insights.

Previous meta-analyzes identified significant variation in response to ocean acidification among broad taxonomic groups ( Kroeker et al ., 2010 ) and suggested there is predictable sensitivity among heavily calcified organisms and higher tolerance among more active mobile organisms (e.g., crustaceans and fish). Variation in sensitivity among calcifying taxa was primarily attributed to differences in life history characteristics, including the degree of control over calcification processes ( Berry et al ., 2002 ; Cohen et al . 2009 ), the presence or absence of biogenic coverings that separate calcified material from seawater (e.g., the periostracum in mussels Ries et al ., 2009 ; Rodolfo-Metalpa et al ., 2011 ), or the amount of calcium carbonate in an organism's shell or skeleton ( Kroeker et al ., 2011a ). However, there is still unresolved variation in sensitivity within these taxonomic groups. Determining whether the remaining variation within taxonomic groups is due to species-specific differences that are inherently difficult to predict, or is due to additional methodological or biological factors remains an important area of research.

Several hypotheses regarding the variation in sensitivity to ocean acidification have been proposed that are not directly related to taxonomic characteristics. For example, acidification's effects can differ across life stages of the same species (e.g., Talmage & Gobler, 2010 ; Albright & Langdon, 2011 ; Crim et al ., 2011 ; Martin et al ., 2011 ). Pronounced sensitivity among a particular life history stage could determine the sensitivity of the species as a whole, but previous meta-analyzes were not able to detect clear patterns among life history stages when all taxa were pooled together ( Kroeker et al ., 2010 ). It was proposed that differences among life stages may be apparent within taxonomic groups, but the lack of studies at the early life history stages of many taxa prevented these comparisons ( Kroeker et al ., 2010 ). Therefore, the emergence of numerous studies on larvae in recent years, may allow a re-evaluation of acidification's impacts across different life history stages.

Recent research has highlighted other factors that may underlie variability in sensitivity among and within taxonomic groups. For example, increased food or nutrient supply can offset reductions in calcification and growth associated with acidification in corals ( Cohen et al . 2009 ; Holcomb et al ., 2010 ) and mussels ( Melzner et al ., 2011 ; Thomsen et al ., 2013 ). Furthermore, adaptation can cause one population to be more or less sensitive than another population of the same species ( Langer et al ., 2009 ; Parker et al ., 2011 ). In addition, some species may be able to acclimate to acidification over longer time frames ( Form & Riebesell, 2011 ), suggesting that the duration of the experiment may influence the species response. As research on ocean acidification has progressed, it is important to understand how the variability due to these factors compares to other known sources of variation.

Moreover, the increasing levels of atmospheric CO 2 are concurrently driving ocean warming ( Meehl et al . 2007 ), and a growing number of experiments have tested the combined effect of ocean acidification and warming. Elevated temperatures can increase the metabolic rate of organisms within their thermal tolerance window, but cause a rapid deterioration of cellular processes and performance beyond tolerance limits ( Pörtner, 2008 ). Hence, predicting the combined effects of warming and acidification is difficult, as warming could either offset the effects of ocean acidification ( McCulloch et al ., 2012 ) or aggravate it through an accumulation of stress effects ( Anthony et al ., 2008 ). As a result, meta-analyzes on the impacts of ocean acidification can now extend beyond preceding efforts by addressing the role of warming on the response of marine biota to acidification.

As research has progressed, it is important to examine how new studies influence our understanding of acidification's impacts. Here, we test the robustness of previous conclusions regarding the sensitivity of various taxonomic groups to ocean acidification to an additional 155 studies (representing approximately 100 new species that were not included in the previous meta-analysis ( Kroeker et al ., 2010 ), which had 79 species). In particular, we used meta-analyzes to test: (i) how taxa vary in key physiological responses, as well as changes in abundance to ocean acidification; (ii) how these effects vary across different life stages within common taxonomic groups; and (iii) how increased temperatures influence the effect of acidification across multiple response variables. We then compare these results to previous analyzes and highlight new insights.

Materials and methods

For these analyzes, we repeated the methods reported in Kroeker et al . (2010 ). First, we identified studies that measured any biological response to ocean acidification published from 1 January 2010 to 1 January 2012 by searching ISI web of science and the European Project on Ocean Acidification (EPOCA) blog ( http://oceanacidification.wordpress.com/ ), as well as the literature cited of the identified studies, resulting in 403 published studies.

We included the data from any study that measured a biological response to a 0.5 unit reduction or less in mean seawater pH (on any pH scale), which reduced the 403 studies to 155 studies. The 0.5 unit reduction in pH was chosen to approximate projections for changes in the global mean surface pH in the near future (i.e., 2100) ( Caldeira & Wickett, 2003 ; Caldeira, 2005 ). Although the magnitude of projected pH reductions varies by location and depth ( Feely et al ., 2009 ), we chose the response to a pH change closest to this global projection (<0.5) to minimize experimental variation. However, we then tested the effect of the magnitude of pH changes on our response estimates (see sensitivity analyzes below).

Although multiple carbonate chemistry parameters will change with acidification, we chose to compare responses with mean reductions in pH, because it is the most commonly reported seawater chemistry parameter that allowed us to best standardize comparisons among experiments. In addition, we chose to use a relative change in pH from the control pH designated by the author of each study (rather than particular pH or pCO 2 values) to allow for differences in the ambient (control) conditions in the system of interest. However, there are still many studies that do not adequately characterize the carbonate chemistry for their study system to know if the designated control is ecologically relevant, and instead rely on global mean pCO 2 levels and projections, despite research that has highlighted the wide range of pH values marine organisms are currently experiencing (e.g., Hofmann et al ., 2011 ). While this is an important area for improvement ( McElhany & Busch, 2012 ), we rely on the authors' designations of control pH for the current analysis, which range from pH T 7.8 to 8.2. The pH total scale is used throughout the study when absolute pH values are indicated.

Data from any experiment that factorially manipulated both carbonate chemistry and temperature were also collected. For these experiments, we analyzed responses at ambient and a 2–3 °C elevated temperature treatment to approximate the projected global averages of near-future warming in the surface ocean ( IPCC, 2007 ). While warming is projected to be more extreme in some areas, all studies had similar temperature manipulations (2–3 °C), which allowed us to standardize among studies.

The choice of which studies to include in meta-analysis can profoundly influence the conclusions ( Abrami et al ., 1988 ; Englund et al ., 1999 ; Osenberg et al ., 1999 ). It is recommended that all relevant data are included in the meta-analysis and that decisions regarding whether studies should be included based on judgments of ‘quality’ be minimized due to issues of bias ( Englund et al ., 1999 ). Instead, running and reporting multiple meta-analyzes with various levels of data selection criteria is recommended to test the robustness of the patterns. Thus, all studies that measured a biological response to a 0.5 unit reduction in pH were included, and several analyzes were used to test the role of data selection criteria and potential methodological sources of variation ( Osenberg et al ., 1999 ). Data points and error estimates were obtained from the EPOCA database ( Nisumaa et al ., 2010 ) or interpolated from figures with graphical software ( data thief iii v. 1.5, Amsterdam, the Netherlands; and graphclick v. 3.0, Neuchâtel, Switzerland).

The data set, comprised of 155 studies, which was then merged with another data set (built with the same methods) that was based on studies published prior to 1 January 2010 ( Kroeker et al ., 2010 ). This combined data set had 228 studies, measuring responses of marine organisms to ocean acidification ( Table S1 ). For each study (i.e., a published article), responses from separate experiments (i.e., independent experiments within a published article) at ambient levels of any other factors (e.g., temperature, nutrients, food supply, light levels) were collected. When ambient food concentrations were not reported, we included the responses of the fed/higher nutrient treatments over the unfed/lower nutrient concentrations. In addition, the differences in responses between the fed/high nutrient and unfed/low nutrient responses were compared with the mean effects and variability for given responses.

Responses from separate species in the same experiment (e.g., species allowed to interact in the same tank) were collected separately. Although, the responses of multiple species from the same experiment are not truly independent, we chose to include multiple species responses from a single experiment, because the indirect effects (e.g., species interactions) of acidification that are nonindependent are very pertinent to global acidification scenarios where species will be experiencing both direct and indirect effects. In addition, multiple lines/populations of the same species from the same experiment were all included for similar reasons. Differences between lines/populations of the same species represent real sources of variability that are the focus of this study. The entire data set primarily consisted of experiments on single species, but also included field experiments (e.g., 18 studies from natural gradients and naturally acidified ecosystems and 21 studies using mesocosms with multiple species).

For each experiment, the effect of acidification was calculated as the log-transformed response ratio ( LnRR ). It is the ratio of the mean effect in the acidification treatment to the mean effect in a control group ( Hedges et al ., 1999 ). Then, the overall mean effect was calculated for each response variable (survival, calcification, growth, photosynthesis, development, abundance, and metabolism) by weighing each individual LnRR by the inverse of the sum of its sampling variance and the between experiment variance, and then calculating the weighted mean (i.e., random effects meta-analysis; Hedges & Olkin, 1985 ). Because of the weighting by variance, any experiment that did not report an error estimate was excluded from the random effects meta-analysis. This resulted in 29 responses excluded from the main analyzes (although they were included in a sensitivity analysis; Fig. S1 ). When a single experiment reported several response variables, we included only one response from an experiment per response variable to avoid pseudoreplication. For example, if an experiment reported the effects on calcification, growth rate, and metabolism, each of those responses were included in the separate meta-analyzes for each response. However, if an experiment reported the effects on various metrics of a response type, such as growth rates based on changes in biomass and length, we included only the most inclusive for that response variable (i.e., we chose to use biomass rather than length to represent growth).

Calcification responses were primarily the estimates of net calcification. Growth responses included estimates of change in biomass, length, width, somatic tissue, and growth rates. Photosynthesis responses included changes in the photosynthetic rate or efficiency. Development responses were primarily based on indices of embryonic or larval development (e.g., percent metamorphosed, percent larvae to reach a certain stage, etc.). Abundance responses encompassed the number of individuals, including the number of newly settled individuals, as well as percent cover estimates. Survival rates were typically reported as the final percent survival or mortality at the end of the experiment, which were then converted to survival. In addition to the analyzes on this raw data, the survival data were also converted into specific daily survival rates to account for differences in the duration of the experiments, and unweighted fixed effects meta-analyzes were performed on LnRR estimates on these duration-weighted, daily survival rates ( Fig. S2 ). Because the focus of this study includes only key physiological and ecological parameters, it should be noted that there are likely to be important effects of ocean acidification that are not captured in this analysis. Several studies report the effects of ocean acidification on reproduction (e.g., fertilization success). However, because this is the subject of several qualitative reviews ( Albright, 2011 ; Byrne, 2011 ; Ross et al ., 2011 ), it is not considered here.

Heterogeneity in mean effect sizes was determined by a significant (α = 0.05) Q T statistic, which is calculated by summing the standard deviation of each effect size from the overall mean effect size estimate, and then weighting each one by the inverse of its sampling variance ( Cochran, 1954 ; Rosenberg et al ., 2000 ). Significant heterogeneity ( Q T ) can indicate that there is underlying data structure that is not adequately captured by the mean effect size (e.g., multiple populations of effect sizes rather than just one population of effect sizes), potentially signaling important sources of biological variation.

The variation in effect sizes among (i) taxa; and (ii) life stages within taxonomic groups was tested with categorical random effects meta-analysis ( Hedges & Olkin, 1985 ). For these analyzes, effect sizes were first partitioned into categories (based on taxonomic groups or life stages within taxonomic groups, respectively). Only the response variables with representative studies in the priori defined categories, and only those categories that had four or more data points for the analyzes were included. The statistic Q M (which quantifies the variation explained by the chosen categories vs. the residual variation, which is defined by Q E ) was then computed to determine whether significant variability is explained by the categories ( Hedges & Olkin, 1985 ; Rosenberg et al ., 2000 ). The significance of Q M was tested by a randomization procedure that randomly re-assigns the effect sizes to the categories to create a probability distribution for mean effect sizes of each category using 9999 iterations ( Rosenberg et al ., 2000 ).

Variation in the effects of acidification at ambient and elevated seawater temperatures was tested by analyzing only those studies that factorially compared both factors (i.e., <0.5 unit reduction in pH combined with a 2–3 °C rise in seawater temperature). We only analyzed the effect of acidification at the ambient seawater temperature (identified by the author of the primary study) in the previous analyzes. In the present analysis, a random effects categorical meta-analysis was performed on (i) the effect of acidification at ambient temperature; (ii) the effect of acidification at an elevated temperature for each different response variable. All meta-analyzes were performed with metawin V. 2.0 (Sinauer Associates).

After meta-analyzes, the mean LnRR estimates were back transformed to mean percent change estimates for ease of interpretation. Because each response ratio was natural log-transformed prior to calculating the mean effect size, the antilog of the mean LnRR was taken to calculate a mean response ratio. Back transformations using the antilog provide a geometric mean of the response ratios, which is known to underestimate the arithmetic mean ( Rothery, 1988 ). However, the underestimation of the arithmetic mean is generally very small ( Hedges et al ., 1999 ). Therefore, reported mean percent change transformations can be considered conservative estimates.

Sensitivity analyzes

To examine the robustness of the results, the Rosenthal's fail-safe number was calculated for each analysis. It estimates the number of nonsignificant results needed to change the significance of the meta-analysis. Furthermore, the disproportionate contribution of an individual experiment with a large magnitude effect size to a given result was tested by (i) ranking each experiment by the magnitude of its effect size; and (ii) individually removing each of the five experiments with the largest magnitude effect sizes from the overall analyzes one at a time and re-running the analyzes. If the exclusion of a single experiment changed the significance of the overall mean effect size or the heterogeneity statistic ( Q T ), we would want to consider removing it from the analysis as it would signal a disproportionate contribution to the overall result. However, this was not the case in any analysis, and all experiments were included. Normality was also checked with normal quantile plots, and non-normal distributions were compensated for by testing the significance of Q T and Q M statistics with randomization tests from 9999 iterations of the data and bootstrapped bias-corrected 95% confidence intervals for the mean effect sizes ( Adams et al ., 1997 ).

Unweighted, fixed effects meta-analyzes were also run for each dataset to examine the role of data selection and weighting on the results ( Englund et al ., 1999 ). This allowed the inclusion of studies that did not report error estimates and that were excluded from the weighted analyzes. Finally, differences in effects sizes due to methodological factors, such as length of experiment or magnitude of pH change, were tested with continuous random-effects meta-analysis ( Rosenberg et al ., 2000 ). Separate analyzes were performed for each taxonomic group with more than 10 data points with either duration of experiment or magnitude of pH change as a continuous variable.

When all taxa are pooled together, ocean acidification had a significant negative effect on survival, calcification, growth, development and abundance ( Fig. 1 ; Table S2 ). Overall, survival and calcification are the responses most affected by acidification, with 27% reductions in both responses, whereas growth and development are reduced by approximately 11–19%, respectively, for conditions roughly representing year 2100 scenarios. On average, the abundance is reduced 15%. In contrast, effects of acidification on photosynthesis and metabolism are not detected, when all taxa are pooled together.

Mean effect of near future acidification on major response variables. Significance is determined when the 95% bootstrapped confidence interval does not cross zero. The number of experiments used to calculate the mean is included in parentheses. *denotes a significant effect.

The magnitude of these effects varies among taxa ( Figs 2 – 4 ; Table S3 ). Reductions in survival are similar among corals, mollusks and echinoderms (although only significant for mollusks), whereas no effect is detected for crustaceans. Corals, coccolithophores, and mollusks show the greatest mean reductions in calcification (22–39%), whereas a significant mean effect of acidification is not detected on the calcification of echinoderms or crustaceans. However, these differences among taxonomic groups are not significant sources of variation in this analysis ( Table S3 ). All calcified taxa show similar magnitude mean reductions in growth (9–17% reductions), although these reductions are only statistically significant for mollusks and echinoderms. Effects on fish growth are not detected, whereas growth increases 22% on average among fleshy algae and 18% among diatoms (growth Q M 8,146 = 70.85, P = 0.001). The effects of acidification on photosynthesis vary little among taxa with the exception of calcified algae, for which photosynthesis is reduced 28% on average (photosynthesis Q M 5,61 = 40.88, P = 0.004). This sensitivity in calcified algae is also apparent in experiments that tested for impacts on abundance, where calcified algae have a much greater mean reduction (80%) in percent cover/abundance in acidified conditions than other groups. In addition, corals suffer significant mean reductions in abundance (47%) in acidified treatments, whereas there is very high variability among other taxa (abundance Q M 6,41 = 42.55, P = 0.005).

Variation in effect sizes among key taxonomic groups, divided by major response variables. Note there are different scales on the y-axes to highlight the variation among taxa. Means are from a weighted, random-effects model with bootstrapped bias-corrected 95% confidence intervals. The number of experiments used to calculate the means is given in parentheses. Not all response variables are considered in this analysis. *denotes a significant difference from zero.

Summary of effects of acidification among key taxonomic groups. Effects are represented as either mean percent (+) increase or percent (−) decrease in a given response. Percent change estimates were back transformed from the mean LnRR , and represent geometric means, that are conservative of the arithmetic means.

In addition, acidification reduces the development of the early life stages of mollusks and sea urchins ( Fig. 3 ; bivalves dominate the mollusk category in 9 of 13 experiments). In comparisons among life stages, the mean effect of acidification on mollusk survival was lowest for larvae ( Q M 2,23 = 3.22, P = 0.05; Fig. 5 ; Table S4 ). This pattern is consistent for the effects of acidification on mollusk metabolism (primarily estimated by oxygen consumption); metabolism is significantly reduced among mollusk larvae and unaffected or increased slightly among adults ( Q M 1,13 = 15.82, P = 0.003; Fig. 5 ). No significant differences in effect sizes are detected among life stages within taxonomic groups for any other response (i.e., the Q M statistics are not significant), including survival of echinoderms or crustaceans, calcification of corals or mollusks, or growth of corals, echinoderms or mollusks ( Fig. 5 ; Table S4 ).

Variation in effects of acidification among taxa for development. Means are from weighted, random effects meta-analysis and are shown with bias-corrected bootstrapped 95% confidence intervals. The number of experiments used to calculate each mean is given in parentheses. *denotes a significant difference from zero.

Significant variation in the effects of near-future ocean acidification among lifestages within taxonomic groups. Error bars represent bias-corrected bootstrapped 95% confidence intervals, and the number of experiments used to calculate the means is shown in parentheses. The * associated with mollusk survival and metabolism denotes a significant difference in effect size among life history stages (Significant Q M ).

The duration of the experiments are heavily skewed towards shorter experiments ( Fig. 6 ), making inferences regarding the influence of experiment duration on effect size problematic. For most taxonomic groups, significant effects of experiment duration on effect size are not detected, while in some limited cases, there is a small but significant effect ( Fig. 6 , Table 1 ). However, the limited number of data points at longer durations strongly influences these patterns, and the shape of the distribution of effect sizes are unknown at longer durations.

The effect of experiment duration on log-transformed response ratio from continuous random effect weighted meta-analysis

The effect of duration of experimental CO 2 enrichment on LnRR . The mean effect size and 95% CI (for all taxa pooled) is shown on the left of each figure (overall), while the individual LnRR estimates for each study are plotted against duration (days) on the right side of the figure for survival, calcification, growth, photosynthesis and development.

The influence of the magnitude of the reduction in seawater pH is not consistent across taxonomic groups and response variables. Similar to the duration analyzes, the effect of the magnitude of the pH change is only detected in a limited number of analyzes ( Table 2 ). These effects are very small, differ in the sign of the slope, and are often heavily influenced by a few responses, analogous to statistical outliers ( Figs S3–S6 ).

The effect of the magnitude of pH reduction on log-transformed response ratio from continuous random effects weighted meta-analysis

There is a trend towards lower survival, growth and development (approximately 8–11%) at elevated temperatures, although these differences are not statistically significant ( Fig. 7 ). Elevated temperature has no clear effect on calcification estimates, and there is a nonstatistically significant trend towards higher photosynthesis in response to acidification in the subset of experiments included in this analysis. However, the differences in effect sizes to exposure to acidification at ambient temperature and at elevated temperature do not explain a significant amount of heterogeneity in any dataset ( Table S5 ).

Variation in effect of acidification treatment at ambient temperature and elevated temperature for different response variables . Means are from weighted, random effects categorical meta-analyses for each separate response variable. Error bars represent bias-corrected bootstrapped 95% confidence intervals, and the number of experiments used to calculate the means is shown in parentheses. *denotes a significant difference from zero.

Rosenthal's fail-safe numbers are large for all analyzes, ranging from 192 to 6157, suggesting that the results are robust. Furthermore, there is no change in significance with the singular removal of any of the experiments with large effect sizes. Therefore, all experiments are included in the analyzes. Additionally, all of the unweighted, fixed effects analyzes reveal very similar patterns to their respective weighted, random effects analyzes ( Fig. S1 ). Finally, while the magnitude of effect size in the duration-weighted survival rate is less than the final estimates of survival, both analyzes reveal very similar patterns (e.g., the significance of the mean effect size did not change for any analysis). The effects of acidification on duration-weighted survival rates are reported in Supporting Information ( Fig. S2 ).

Our results reveal reductions in survival, calcification, growth, development, and abundance in response to ocean acidification across a broad range of marine organisms. These results support the findings of previous meta-analyzes ( Kroeker et al ., 2010 ) and suggest that the effect of ocean acidification will be widespread across a diversity of marine life. In addition, the analyzes reveal significant trait-mediated variation in the sensitivity of marine organisms. In general, heavily calcified organisms, including calcified algae, corals, mollusks, and the larval stages of echinoderms, are the most negatively impacted, whereas crustaceans, fish, fleshy algae, seagrasses and diatoms are less affected or even benefit from acidification ( Fig. 4 ) whereas some fleshy algae and diatoms may benefit, although marginally, from the same conditions ( Koch et al ., 2013 ). These results support previous analyzes despite the tripling of studies and the doubling of species included in the analyzes, suggesting that species' traits (taxonomic group) may be a robust factor for forecasting species sensitivity to acidification.

Most of the mean effect size estimates fall within the 95% confidence intervals of the previous meta-analysis ( Kroeker et al ., 2010 ), with the exception of crustaceans. The mean effect of acidification on crustacean calcification and growth fall outside of the previous 95% confidence intervals and are more negative in both cases (although not statistically significant) primarily due to the addition of two studies examining barnacles ( Findlay et al ., 2010a , b ). These results suggest that the growth and calcification of heavily calcified barnacles may be more susceptible to acidification than other mobile crustaceans. Generally, the other mean effect size estimates (those within previous 95% confidence intervals) do not follow directional patterns (i.e., some increase, whereas others decrease slightly) suggesting that reported patterns are robust.

While the broad scale patterns are robust, new insight is gained by examining the body of studies published in recent years. Whereas the mean effect of acidification on mollusks was not significant for any response variable in a previous meta-analysis ( Kroeker et al ., 2010 ), the power provided by the additional 39 recent studies published reveal significant reductions in calcification (40%), growth (17%) and development (25%) of this group. When compared with other taxa, these new results suggest that mollusks are one of the groups most sensitive to acidification ( Fig. 4 ), suggesting the exposure of early life stages of mollusks to acidification may represent a bottleneck for their populations ( Talmage & Gobler, 2010 ; Crim et al ., 2011 ; Hettinger et al ., 2012 ). The slower development of mollusk larvae supports this result as well ( Fig. 3 ). Indeed, the results from the present meta-analysis are consistent with recent evidence suggesting that oyster larvae in hatcheries in the Northeast Pacific Ocean are very sensitive to acidification and are already being impacted by low pH waters ( Barton et al ., 2012 ). Furthermore, recent studies suggest that carry-over effects between life history stages of mollusks can influence the response at later life stages ( Hettinger et al ., 2012 ; Parker et al ., 2012 ).

The increase in the number of studies considering multi-species responses to acidification allows the first synthetic analysis of abundance patterns. Species abundance patterns are of particular interest, because it integrates many of the physiological effects of acidification, as well as indirect effects via species interactions when quantified in a multi-species assemblage. Most of the abundance estimates in this meta-analysis are from multi-species assemblages (75% for mollusks, 90% for corals and 100% for calcifying algae, crustaceans and fleshy algae), with the exception of coccolithophores and diatoms for which the studies are more often focused on specific growth rates of single species. The results reveal considerably more variability in the effects of acidification on abundance than the other response variables (note the large confidence intervals and larger scale in Fig. 2 ), especially among mollusks and crustaceans. This suggests that species interactions may decrease the predictability in species responses ( Fabricius et al ., 2011 ; Hale et al ., 2011 ; Kroeker et al ., 2011b ). Indeed, studies examining impacts of acidification on multi-species assemblages have reported opposing responses of closely related species within the same assemblage, potentially due to compensatory dynamics among the most tolerant species ( Fabricius et al ., 2011 ; Hale et al ., 2011 ; Kroeker et al ., 2011b ; Porzio et al ., 2011 ). Abundance estimates are based upon results from four field studies in three naturally acidified ecosystems, two field mesocosms, and 29 laboratory studies containing multiple species ( Table S1 ), suggesting the results are not biased by a specific approach.

Another important insight in the abundance analysis concerns the early life stages of corals. All abundance estimates for corals used here are focused on the percent settlement of coral spat ( Table S1 ), whereas other response variables mostly estimate the effects of acidification on adult corals. The effect of acidification on coral abundance was greater than its effect on any other response (e.g., abundance is reduced on average 47%, while other response variables are reduced less than 34%). In several studies, this response was dependent on the exposure of the settlement substrate to reduced pH seawater, suggesting ocean acidification affects coral settlement indirectly by affecting the community composition (primarily crustose coralline algae and/or microbial biofilms) or biological and chemical settlement cues ( Albright et al ., 2010 ; Albright & Langdon, 2011 ). These results suggest that the settlement of coral larvae may be particularly sensitive to acidification and could also represent a bottleneck for population dynamics of corals in acidified conditions ( Albright et al ., 2010 ; Albright & Langdon, 2011 ; Doropoulos et al ., 2012 ).

While the effects of acidification on the early life stages of mollusks and coral settlement (abundance) are significant, the sensitivity of early life stages of other taxa are not clear in other categorical meta-analyzes ( Fig. 5 ). These results suggest that the amount of variation due to differences in sensitivity among life stages may be relatively small compared with other sources of variation for some groups. Thus, it is suggested that the identification of potential life history bottlenecks may be best approached at a finer taxonomic resolution for these groups (i.e., quantifying variation in sensitivity of life stages within specific species).

Although the differences between acidification effects at ambient and elevated temperature do not explain a significant amount of variation, there is a trend towards lower survival, growth and development at elevated temperature. Given the significant variation already attributed to taxonomic groups and life history stages, the inability to detect statistically significant differences does not suggest that increased temperature does not affect the response to ocean acidification. It rather suggests that other sources of variation in these analyzes may be more pronounced than the difference in effect size at ambient and elevated temperatures. However, the trend towards lower survival, growth and development on average at elevated temperatures, suggest that continued research on the combined impacts of acidification and warming may be critical for accurately forecasting marine species responses to acidification in the near future.

When all taxa are pooled together, the effects of elevated temperature on species responses to acidification are clearly not apparent for calcification. Modeling efforts have highlighted how warmer temperatures that increase calcium carbonate precipitation kinetics can potentially offset the reduction in calcification caused by lower pH in some species of corals that are able to up-regulate internal pH ( McCulloch et al ., 2012 ). However, this response is limited to certain species and to temperature increases that are within the thermal tolerance of the organism ( Pörtner, 2008 ). Nonetheless, the analysis does contain several studies on corals (10 of 18 experiments examined the response of corals), and increased kinetics due to warmer temperatures could in part explain the insensitivity of the acidification-driven calcification response to increased temperature. Additional studies have suggested that temperature and acidification affect different pathways, with temperature overriding the effects on survival ( Findlay et al ., 2010a ; Lischka et al ., 2011 ) and ocean acidification affecting calcification more specifically. Thus, while there is some evidence for synergistic effects of temperature and acidification in some studies ( Reynaud et al ., 2003 ; Anthony et al ., 2008 ; Rodolfo-Metalpa et al ., 2010 ), our results suggest that this is not the norm in experiments examining their combined impact on calcification (see Comeau et al ., 2010 ).

While the meta-analyzes can explain some variation in responses based on biological traits, the remaining variation within taxonomic groups is still of real ecological interest. Although this remaining variation could represent species-specific sensitivities, the importance of context has recently become more apparent. For example, the responses of both corals and mussels to acidification have been shown to be dependent on their food supply ( Holcomb et al ., 2010 ; Melzner et al ., 2011 ). Although the available studies are few, we found that the difference in LnRR estimates between unfed/low nutrient vs. fed/high nutrient species within in single study can sometimes span or exceed the size of the 95% confidence interval for coral calcification ( Holcomb et al ., 2010 ; Melzner et al ., 2011 ; Edmunds 2011 ). For example, the range of LnRR estimates of coral calcification in zooxanthellate corals ( Astrangia poculata ) between high and low nutrient concentrations (i.e., the difference between high and low nutrient treatments = range = 1.0 LnRR ; Holcomb et al ., 2010 ) is more than double the 95% confidence interval for coral calcification (95% CI = 0.48). However, the range of area-normalized calcification LnRR estimates between Porites spp. with and without heterotrophic feeding (range = 0.22 LnRR ; Edmunds 2012) is about half the 95% CI. In another example, the range of growth estimates of mussels ( Mytilus edulis ) between high and low food concentrations (range = 0.08 LnRR; Melzner et al ., 2011 ) is also approximately half the 95% confidence interval for mollusk growth (95% CI = 0.21 LnRR ). While the examples are few, these results suggests that nutritional status is not trivial in determining species sensitivity to acidification and should be considered to control for sources of variability.

In addition, populations can be locally adapted to different environmental conditions ( Sanford & Kelly, 2010 ) and respond differently to the same acidification stress ( Langer et al ., 2009 ; Sunday et al ., 2011 ; Pistevos et al ., 2011 ; Parker et al ., 2011 ). For example, the range of LnRR estimates for growth among selectively bred lines of the Sydney rock oyster (range = 0.72 LnRR ; Parker et al ., 2011 ) was over three times the 95% confidence interval for the mean effect of acidification on mollusk growth (95% CI = 0.21 LnRR ). In another example, the range of LnRR estimates for growth of different strains of the coccolithophore Emiliania huxleyi (range = 0.47 LnRR ; Langer et al ., 2009 ), almost doubles the 95% confidence interval for coccolithophore growth (95% CI = 0.28 LnRR ). In many cases, the response of a single population is reported as if it was the response of the entire species. As the field progresses, care must be taken into account for and report factors such as location for source populations and background environmental conditions of source populations ( McElhany & Busch, 2012 ) to refine our understanding of acidification's biological impacts.

Despite the growing interest in acclimation to ocean acidification ( Evans & Hofmann, 2012 ), a signal of acclimation is not clear in this data set (i.e., it is not clear whether organisms exposed to acidification for longer durations are less affected than those in short-term experiments). While the analyzes highlight high variability in the short-term experiments, the few experiments at longer durations fall well within the range of effects in short-term experiments and are still well-estimated by the mean effect sizes ( Fig. 6 ). Additional experiments for extended durations, are needed to understand whether the distribution of effect sizes shifts or becomes smaller (i.e., the variability is reduced) over time. However, field studies have shown that species respond to relatively short fluctuations in carbonate chemistry (e.g., diel fluctuations) even when they experience these conditions regularly ( Price et al ., 2012 ). Thus, although short-term studies may not address acclimation potential, the results are still informative and can be ecologically relevant.

While the magnitude of the pH change does not consistently explain a significant amount of variability, it does not necessarily indicate that the magnitude of ocean acidification will not influence species responses. Instead, other sources of variation could be masking a potential relationship between the responses of taxonomic groups and the degree of acidification, including methodological sources of error or true biological sources of variation. In addition, the relationship between the magnitude of pH changes and species responses could be nonlinear, and/or more pronounced changes could be detected in lower pH conditions ( Scheffer & Carpenter, 2003 ; Ries et al ., 2009 ; Christen et al ., 2012 ).

In conclusion, analysis of the rapidly expanding body of research on acidification reveals consistent reductions in calcification, growth, and development of a range of calcified marine organisms, despite the variability in their biology. While our syntheses suggest that some taxa may be predictably more resilient or may benefit from ocean acidification (e.g., brachyuran crustaceans, fish, fleshy algae, and diatoms), it should be noted that a decrease in pH is also likely to have effects that are not captured in the physiological and ecological response variable synthesized here. For example, acidification appears to have neurological effects on fish with repercussions for their behavior ( Nilsson et al ., 2012 ), whereas some marine plants appear to lose the phenolic compounds used as herbivore deterrents under acidified conditions ( Arnold et al ., 2012 ). Furthermore, the potential for acclimation ( Evans & Hofmann, 2012 ) or adaptation ( Sunday et al ., 2011 ; Lohbeck et al ., 2012 ) in response to acidification could potentially lessen the effects on calcified taxa synthesized here and remain critical areas for future research. While physiological effects on these calcified organisms can result in decreases in their abundance, the higher variability in species responses in multi-species studies indicates that species interactions will also be important determinants of abundance ( Fabricius et al ., 2011 ; Kroeker et al ., 2011b ). Furthermore, understanding whether the remaining variation within taxonomic groups and life stages represents real biological differences among species, locally adapted populations, or acclimatory capacities, rather than experimental error, remains a critical area for future research. Finally, marine organisms of the future will not be subjected to acidification in isolation, and our results suggest that continued research on the concurrent effects of warming and acidification is necessary to forecast the status of marine organisms and communities in the near-future.

Acknowledgments

Thanks are due to C.D.G. Harley and two reviewers for comments on an early version of this manuscript and A.-M. Nisumaa for her help with data compilation. This study is a contribution to the European Project on Ocean Acidification (EPOCA) and the MedSeA project (Contract #265103), with funding from the European Community's Seventh Framework Programme. Scientific illustrations are courtesy of the Integration and Application Network ( http://ian.umces.edu/symbols/ ), University of Maryland Center for Environmental Science.

Supporting Information

Additional Supporting Information may be found in the online version of this article:

Figure S1 . Unweighted, fixed effects meta-analyzes.

Figure S2 . Comparison of total percent survival and calculated daily survival rate estimates (weighted by the duration of the study) pooled for all taxa.

Figure S3 . Effect of pH change on LnRR estimates of survival among taxonomic groups.

Figure S4 . Effect of pH change on LnRR estimates of calcification among taxonomic groups.

Figure S5 . Effect of pH change on LnRR estimates of growth among taxonomic groups.

Figure S6 . Effect of pH change on LnRR estimates of photosynthesis among taxonomic groups.

Table S1 . Studies used for analyzes (excel file).

Table S2 . Statistics for overall analyzes.

Table S3 . Statistics for categorical taxonomic analyzes.

Table S4 . Statistics for categorical life stage analyzes within taxonomic groups.

Table S5 . Statistics for categorical temperature analyzes.

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ENCYCLOPEDIC ENTRY

Marine pollution.

Marine pollution is a combination of chemicals and trash, most of which comes from land sources and is washed or blown into the ocean. This pollution results in damage to the environment, to the health of all organisms, and to economic structures worldwide.

Biology, Ecology, Earth Science, Oceanography

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• Marine Pollution (Google Doc)

Marine pollution is a growing problem in today’s world. Our ocean is being flooded with two main types of pollution: chemicals and trash.

Chemical contamination, or nutrient pollution, is concerning for health, environmental, and economic reasons. This type of pollution occurs when human activities, notably the use of fertilizer on farms, lead to the runoff of chemicals into waterways that ultimately flow into the ocean. The increased concentration of chemicals, such as nitrogen and phosphorus, in the coastal ocean promotes the growth of algal blooms , which can be toxic to wildlife and harmful to humans. The negative effects on health and the environment caused by algal blooms hurt local fishing and tourism industries.

Marine trash encompasses all manufactured products—most of them plastic —that end up in the ocean. Littering, storm winds, and poor waste management all contribute to the accumulation of this debris , 80 percent of which comes from sources on land. Common types of marine debris include various plastic items like shopping bags and beverage bottles, along with cigarette butts, bottle caps, food wrappers, and fishing gear. Plastic waste is particularly problematic as a pollutant because it is so long-lasting. Plastic items can take hundreds of years to decompose.

This trash poses dangers to both humans and animals. Fish become tangled and injured in the debris , and some animals mistake items like plastic bags for food and eat them. Small organisms feed on tiny bits of broken-down plastic , called micro plastic , and absorb the chemicals from the plastic into their tissues. Micro plastics are less than five millimeters (0.2 inches) in diameter and have been detected in a range of marine species, including plankton and whales. When small organisms that consume micro plastics are eaten by larger animals, the toxic chemicals then become part of their tissues. In this way, the micro plastic pollution migrates up the food chain , eventually becoming part of the food that humans eat.

Solutions for marine pollution include prevention and cleanup. Disposable and single-use plastic is abundantly used in today’s society, from shopping bags to shipping packaging to plastic bottles. Changing society’s approach to plastic use will be a long and economically challenging process. Cleanup, in contrast, may be impossible for some items. Many types of debris (including some plastics ) do not float, so they are lost deep in the ocean. Plastics that do float tend to collect in large “patches” in ocean gyres. The Pacific Garbage Patch is one example of such a collection, with plastics and micro plastics floating on and below the surface of swirling ocean currents between California and Hawaii in an area of about 1.6 million square kilometers (617,763 square miles), although its size is not fixed. These patches are less like islands of trash and, as the National Oceanic and Atmospheric Administration says, more like flecks of micro plastic pepper swirling around an ocean soup. Even some promising solutions are inadequate for combating marine pollution. So-called “ biodegradable ” plastics often break down only at temperatures higher than will ever be reached in the ocean.

Nonetheless, many countries are taking action. According to a 2018 report from the United Nations, more than sixty countries have enacted regulations to limit or ban the use of disposable plastic items. The National Geographic Society is making this content available under a Creative Commons CC-BY-NC-SA license . The License excludes the National Geographic Logo (meaning the words National Geographic + the Yellow Border Logo) and any images that are included as part of each content piece. For clarity the Logo and images may not be removed, altered, or changed in any way.

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Essay on Water Is Life

Students are often asked to write an essay on Water Is Life in their schools and colleges. And if you’re also looking for the same, we have created 100-word, 250-word, and 500-word essays on the topic.

Let’s take a look…

100 Words Essay on Water Is Life

Importance of water.

Water is a vital resource for all living beings. It is essential for our survival. Without water, life on earth would not exist.

Role in Our Body

Water makes up about 70% of our body. It helps in digestion, circulation, and maintaining body temperature.

Water in Nature

Water forms rivers, oceans, and rains that nourish the earth. It is crucial for the growth of plants and animals.

Conservation

Water is a limited resource. We must conserve it to ensure a healthy future for our planet.

Also check:

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250 Words Essay on Water Is Life

Introduction.

Water, a simple molecule composed of two hydrogen atoms and one oxygen atom, is the lifeblood of our planet. It is the most abundant and essential resource, without which life as we know it would not exist.

The Essence of Life

Water is the fundamental building block of life. It is involved in every bodily function, from digestion and circulation to temperature regulation and waste removal. The human body is approximately 60% water, reflecting its importance in maintaining life and health.

Water and the Environment

Water’s role extends beyond the individual organism. It is integral to maintaining Earth’s delicate ecosystems. Water cycles through our environment, from the atmosphere to the earth and back again, supporting plant and animal life, shaping landscapes, and influencing climate patterns.

The Social and Economic Impact of Water

Water also plays a significant role in social and economic structures. It is vital for agriculture, industry, and energy production. Access to clean water is a determinant of societal health and prosperity. Yet, water scarcity, pollution, and mismanagement pose major challenges, with profound implications for human rights, social equity, and global stability.

In conclusion, water is life. It is the essence of biological function, the driver of ecological systems, and the underpinning of social and economic structures. As we face a future of increasing water scarcity and pollution, understanding and respecting the critical role of water is more important than ever. We must strive to conserve and protect this invaluable resource, for it is not just water, but life itself.

500 Words Essay on Water Is Life

The essence of life: water.

Water, the most vital natural resource, is the lifeblood of every living organism on Earth. From microscopic organisms to the largest mammals, all life forms depend on water for survival. This universal solvent, often referred to as the “elixir of life,” performs essential roles in biological processes, climatic regulation, and economic development.

Water: The Biological Imperative

Water is crucial to the existence and sustenance of life on Earth. It comprises about 60-70% of a human body, acting as a medium for biochemical reactions, a transporter of nutrients and waste, and a temperature regulator. It is the primary component of cells, tissues, and organs, and without it, life as we know it would cease to exist.

In the plant kingdom, water is instrumental for photosynthesis, the process by which plants produce food. It also facilitates the transportation of nutrients from the roots to other parts of the plant. Hence, the absence of water would disrupt the food chain, leading to catastrophic effects on all life forms.

Water and Climate

Water plays a significant role in regulating Earth’s climate. The hydrological cycle, involving evaporation, condensation, precipitation, and runoff, is a key driver of weather patterns. Oceans, which hold about 97% of Earth’s water, absorb heat from the sun and distribute it around the globe through ocean currents, thereby moderating global temperatures.

Furthermore, water in the form of ice at the poles and high altitudes reflects sunlight back into space, helping to stabilize Earth’s temperature. The melting of this ice due to global warming is a cause for concern as it could lead to a rise in sea levels and drastic changes in climate.

Economic Importance of Water

Water is indispensable for economic development. It is essential for agriculture, which is the primary source of livelihood for a large portion of the global population. Industries such as power generation, manufacturing, and tourism also rely heavily on water. Moreover, waterways serve as important routes for trade and transportation, contributing significantly to the global economy.

Water Scarcity and Conservation

Despite its abundance, water scarcity is a pressing issue in many parts of the world due to factors like overpopulation, overexploitation, pollution, and climate change. This underscores the need for efficient water management and conservation.

Water conservation can be achieved through strategies like rainwater harvesting, recycling and reusing wastewater, and adopting water-efficient technologies. It is also crucial to create awareness about the importance of water and the need for its conservation.

In conclusion, water is not just a life-sustaining resource but the very essence of life. It is a critical component of biological processes, a key climate regulator, and an economic catalyst. However, the growing water scarcity necessitates urgent action to conserve and manage this invaluable resource. As we recognize water’s integral role in our lives, it becomes our collective responsibility to ensure its availability for future generations. After all, water is life.

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Aquatic Life in Indiana Problem Solution Essay

Problem statement, background of the issue, work through an issue or work around an issue, political, economic, societal, and environmental consequences of the pathways, works cited.

Due to the increase of motor boating in public freshwater lakes of Indiana, environmental degradation has risen in the area. There seems to be no substantive laws and regulations to curb the rise of engine propelled boats. The following goals (targets) are important in order to fix the apparent problem.

• Indiana ought to reduce the emissions of the motor boats and other recreational equipments that endanger aquatic life of natural rivers and lakes.
• Improvement of partnership relations between private and public organizations to enhance environmental custodianship is a desirable condition.
• Rehabilitation of various freshwater lakes in order to conserve the marine ecology is important for the area.

To achieve the goal of reducing emissions that endanger the aquatic life of freshwater lakes and rivers in Indiana, various pathways are crucial. They include:

• Agitating for enactment of laws that encourage ecotourism and limit the amount of harmful emissions by high-speed motor boats and other equipments of recreation is a major pathway.
• Identifying potential eco-zones in shallow lakes is a pathway that will deter boats from visiting the areas.
• Active participation by all stakeholders and community of Indiana should serve as a pathway that will enhance responsiveness of people towards the endangered rivers and shallow lakes.

According to Hill, technology has played a significant role of supporting tourism and recreation (33). The demand for motor boats has risen across the United States and the entire world. In Indiana, the number of registered and unregistered high-speed boats has tripled in the last three decades. In 2010, Indiana had a high number of registered motor boats that surpassed 280,000 (Seba 71).

This was a sharp increase of 29% from 2000 (Baromey 31). Consequently, high-speed motor boats have led to a form of recreation that is harmful to the environment. While it is imperative to underscore the role of technology in social and economic development, it is agreeable that the effects of motor boating in shallow lakes of Indiana are apparent and detrimental.

At the outset, Hill argues that high-speed boats are detrimental to aquatic environments and near-shore ecologies (45). The rationale is that over 60% of motor boats that operated in 2011 emitted harmful compounds and greenhouse gases owing to their consumption of fossil fuels to propel their engines (Seba 3).

High-speed motor boating leads to incidences of noise pollution, fossil fuel emissions and degradation of shorelines (Honey 39). This does not only affect the life of animals living in freshwater lakes and rivers but also the people utilizing the recreational facilities.

Hill points out that the question of whether or not motor boating is detrimental to aquatic life requires various perspectives and point of views (46). It is important to note that motor boating has not only increased the utilization of recreational facilities but is a major source of revenues for public institutions. In fact, US authorities recognize the role of motor boating in the economy and tourism (Zieman 134).

Nonetheless, new laws have emerged to enhance environmental custodianship in many parts of the country. This is not the case in Indiana. Current laws in Indiana that aim at regulating high-speed boating have not achieved their goals (Honey 39). In particular, Indiana’s laws do not classify specific regions within freshwater lakes according to their vulnerability and susceptibility to environmental degradation (Rodgers and Smith 140).

It is therefore difficult for motor boaters to comprehend the actual impacts of boating on shallow lakes within the region. To that end, it is essential for the regulatory authorities to enact laws that promote ecotourism.

Due to the importance of technology in enhancing reactionary activities, ecotourism has emerged as a major pathway through which Indiana can reduce the amount of fossil fuel emissions by the motor boats (Baromey 61). In fact, the concept of ecotourism advocates for a specific form of leisure that takes into account the environmental concerns raised by societies (Rodgers and Smith 143).

It is sensitive to the environment and it advances the notion that environment is a central aspect of tourism. For instance, ecotourism does not advocate for high-speed boating in shallow lakes (Zieman 135). To that end, motor boating is only possible in deep lakes and rivers in order to avoid the apparent and negative effects of high-speed boating.

It is important to mention that many sectors of tourism have embraced the concept of ecotourism in order to conserve and preserve the natural environment (Seba 72). This has enabled various public institutions to remain profitable without endangering the environment.

In addition, the concept of ecotourism has demystified the notion that regulation of motor boating activities in shallow lakes will eventually reduce revenues for the stakeholders. According to ecotourism statistics, over 79% of countries and institutions that have adopted ecotourism practices have reported increments in their profit margins over time (Seba 73).

Working through an issue involves unraveling causative factors and addressing them continuously (Buckley 63). It also involves the ability to understand the issue from firsthand experience. Active participation by all stakeholders is a central aspect of working through an issue. Every member of the society plays an important role of ensuring that the issue is addressed amicably.

While proponents of the process say that it lead to the achievement of anticipated outcomes, opponents point out that working around an issue is the best way to address a situation. In fact, they argue that working through an issue is time consuming and may require more resources than other conventional ways of resolving problems (Seba 79). Working around a problem is a subjective way of identifying and resolving problems.

The problem solver identifies the issue and recommends ways to resolve it. As such, working around the problem does not always yield results that are desirable by the entire society.

It is important to mention that I prefer working through a problem as opposed to working around an issue. The rationale is that it involves all stakeholders and ensures that the problem is monitored overtime (Seba 85). This does not only enhance problem solution but also ensures that the problem does not occur in the future.

In addition, working through a problem is an objective way of resolving problems acceptably (Buckley 106). It has the goodwill of all stakeholders and involves almost all interested parties. For instance, all stakeholders will play a role in an effort to reduce emission of motor boats in Indiana.

Various pathways will have political, economic, societal and economic consequences. At the outset, agitating for enactment of laws and regulations to guide motor boating in Indiana may have various consequences. Due to the sensitivity of the issue, major motor boat manufacturers may lobby various political actors to impede the enactment of new laws.

Nonetheless, adoption of eco-friendly laws will guarantee the society of sustainable recreational facilities. This in turn will spur economic activities associated with tourism in the entire city of Indiana (Buckley 101). Over and above, passage of new laws that aim at protecting and preserving natural lakes and rivers will have a positive impact on the environment.

The second pathway involves mapping and identifying eco-zones within the rivers and shallow lakes of Indiana. This will result to a boost in environmental conservation and enhance economic sustainability of Indiana’s tourism sector. Undoubtedly, mapping and identifying eco-zones may lead to overcrowding in some areas where motor boating will persist.

This may predispose the society to the risk of high concentration of pollutants in some specific areas. Finally, the third pathway entails rehabilitating the endangered freshwater lakes. This is possible by enhancing active participation and partnership of all stakeholders. Politically, the pathway will provide a platform where all stakeholders will discuss and contribute towards addressing the issue of motor boating.

It will also encourage the growth of positive partnership between political and social institutions. Moreover, the society will play a significant role in identifying the appropriate solution. Consequently, public awareness on the problem of motor boating will increase since all societal members are active participants in the entire process (Buckley 101).

Finally, involvement of major partners and stakeholders will contribute towards sustainable recreational practices. This will not only benefit the community but also ensure that Indiana’s freshwater lakes and rivers begin to support marine ecology once again.

Baromey, Neth. Ecotourism as a Tool for Sustainable Rural Community Development, New Jersey: Prentice Hall, 2008. Print.

Buckley, Ralf. Environmental Impacts of Ecotourism, New York: McGraw Hill, 2004. Print.

Hill, Daniel. “Physical Impacts of Boating on Lakes.” Journal of Sustainable Development, 3.5 (2004): 238-250. Print.

Honey, Martha. Ecotourism and Sustainable Development, London: Blackwell Press, 2008. Print.

Rodgers, Jermain and Smith, Heath. “Buffer Zone Distances to Protect Foraging and Loafing Waterbirds from Human Disturbance in Florida. Wildlife and Social Bulletin, 25.1 (2007):139-145. Print.

Seba, Jaime. Ecotourism and Sustainable Tourism: New Perspectives and Studies , New York: Sage Publishers, 2011. Print.

Zieman, John. “The Ecological Effects of Physical Damage from Motor Boats on Turtle Grass Beds In Southern Florida.” Aquatic Bulletin, 2.2 (1996):127-139.Print.

• Chicago (A-D)
• Chicago (N-B)

IvyPanda. (2023, December 18). Aquatic Life in Indiana. https://ivypanda.com/essays/aquatic-life-in-indiana/

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Bibliography

IvyPanda . "Aquatic Life in Indiana." December 18, 2023. https://ivypanda.com/essays/aquatic-life-in-indiana/.

• The Bart’s Basic Boating Database
• An analysis of the Luncheon of the boating party
• Chattahoochee River National Recreation Area
• The Ocean Pollution Problem Overview
• Polluted Indian River Lagoon Hurts the Local Economy
• The Failure of the Assimilation
• Hotel Services and Pricing Strategies
• Trends in Ecotourism
• Eco-Tourism and Eco-Cities
• Strategic Plan for the Indiana Automotive Industry
• Energy and Society Carbon Footprint
• The Effect of the Ozone Layer on the earth
• Responsibility and Attributes towards the Natural World
• BHP Waste Managements: Environmental Justice
• Water Pollution and Its Challenges

Movie Reviews

Tv/streaming, collections, great movies, chaz's journal, contributors, the wes anderson collection, chapter 4: "the life aquatic with steve zissou".

When I tell people that my favorite Wes Anderson movie is " The Life Aquatic with Steve Zissou ," they look at me funny. And why wouldn't they? Cowritten with Noah Baumbach (" Kicking and Screaming ," " The Squid and the Whale "), it's Anderson's longest, strangest, most tonally and (perhaps) visually ambitious picture, and it made about eight dollars at the box office and was despised by critics. 

I exaggerate, but only slightly. This is, point of fact, Wes Anderson's biggest-budgeted production, and his biggest disappointment in relation to cost. When it hit theaters in late 2004, few American critics had anything good to say about it. I was in that minority , as was my New York Press colleague Armond White and...not too many others that I know of. At the New York Critics Circle voting meeting that year, I proposed it for awards in a number of categories, including best director and cinematography, knowing that the suggestion would inspire eye-rolls and derisive laughter, because I hoped that maybe somebody in the room would think, "Hey, if he really loves it that much, maybe there's something to it after all, and I should give it another chance." I don't think there were any takers. To love "The Life Aquatic" felt, at the time, a bit insane. Maybe it still does. It's his least perfect movie, without a doubt. It's almost certainly too long, and there are sections that drag or feel somehow off or that just flat-out don't quite work, at least not as they needed to in order to please a wide audience. But it's wonderful all the same. I cherish its imperfections to the point where they no longer seem like imperfections.  

I love how Roger Ebert's review of "The Life Aquatic" quotes a cutting phrase from his TV review of the film, but in service of what already feels like a revision: "My rational mind informs me that this movie doesn't work. Yet I hear a subversive whisper: Since it does so many other things, does it have to work, too? Can't it just  exist?  'Terminal whimsy,' I called it on the TV show. Yes, but isn't that better than half-hearted whimsy, or no whimsy at all? Wes Anderson's 'The Life Aquatic with Steve Zissou" is the  damnedest  film. I can't recommend it, but I would not for one second discourage you from seeing it.'"

My already great admiration for the film grew as I dealt with a string of deaths between 2006 and 2009—my wife, my best friend and my stepmother, one after the other. 

I watched "The Life Aquatic" a couple of times a year during that period. Each time it helped me a bit more, for reasons I get into in this video essay, as well as in the forthcoming fourth chapter, about the similarly-death-haunted "The Darjeeling Limited." 

Few American directors are as obsessed with the continuing psychic aftershocks of loss as Anderson, as this film, "Darjeeling" and "The Royal Tenenbaums" and "Rushmore" make plain. And yet somehow his movies don't feel morbid. They take a marvelously balanced attitude, cherishing all the bustle and humor and pettiness and absurdity and other mundane realities that make up daily life in the aftermath of catastrophe, but without minimizing the burden of all that weight. This is is one of the very few movies that I can unhesitatingly say made a tangible, positive difference in my life.  

I've reprinted a version of the "Life Aquatic" essay that appears in "The Wes Anderson Collection." It's quite a bit longer than the version that made print, with more digressions, but considering the subject, that seems somehow fitting.

"I'm going to go on an overnight drunk, and in ten days I'm going to set out to find the shark that ate my friend and destroy it. Anyone who wants to tag along is more than welcome." 

With that declaration, the naturalist/director/pothead hero of The Life Aquatic with Steve Zissou drags the crew of his research vessel The Belafonte on a mission to kill the dreaded Jaguar Shark. It sounds like the plot of a sci-fi thriller, or maybe the umpteenth retelling of Moby Dick or Jaws or some other nautical epic. But while Wes Anderson's fourth film draws on these modes and others, it's defiantly unique. Like its predecessor The Royal Tenenbaums , but more so, Aquatic anchors its dazzling images and zig-zaggy detours to strong, basic themes: the lived experience of grief; the futility of revenge; the anxiety of entering middle age and wondering if you'll leave a legacy along with your unfinished business. 

Dry comedy segues into romance, farce, violence and deep sorrow. There are lyrical montages, funky action setpieces and shots of obviously stop-motion animated sea creatures with made-up names: sugar crab, golden barracuda, crayon pony fish. Cowritten with Noah Baumbach, The Life Aquatic is patchwork personal expression on a grand scale. It's as simultaneously old-yet-new-seeming as Zissou's boat, a refurbished World War II frigate containing a research lab, a movie studio, and spa with a sauna designed by an engineer from the Chinese space program. No wonder it was a critical and commercial disappointment: it's as immense and weird yet clearly personal as Jacques Tati's Playtime , Steven Spielberg's 1941 , Martin Scorsese's New York, New York , and Francis Coppola's One from the Heart -- box-office bombs whose reputations grew over time. 

There's a bright spot: the possibility that a young acolyte turned investor, Air Kentucky pilot Ned Plimpton (Anderson's regular collaborator Owen Wilson ), might be his illegitimate son. Of all Anderson's charismatic fathers and father figures, Steve is the most complex and contradictory. He's Jacques Cousteau, Captain Ahab and Andy Hardy rolled into a spliff and smoked by Tommy Chong . His flaky sincerity that undercuts his arrogance and makes him seem, if not lovable, then at least tolerable, and sometimes pitiable. As Zissou, Murray is at once exuberant and depressed, bitter and open-hearted.  It might be his most stylized yet human-scaled performance, rivaled only by his work as the hero of Jim Jarmusch's Broken Flowers, another middle-aged stud who suffers an existential crisis when he learns that he might have a son he didn't know about. 

Steve and Ned's maybe father-son relationship is thrown off-balance when Steve falls for the pregnant Jane, then loses her to the man-child Ned. This awkward love triangle is awkward but ultimately healing, and it releases prismatic new colors in the characters. It's like a hall of mirrors that obliterates labels, blurs boundaries and makes everyone resemble everyone else. Ned was raised by a single mom that he recently lost to cancer -- the same woman Steve seduced and abandoned decades ago. Jane is a single mother who was knocked up and abandoned by her editor. Steve lost two seeming father figures, Esteban and his mentor Lord Mandrake, to death, and his mate Eleanor to divorce. Like Rushmore 's Max Fischer and Herman Blume, Steve and Ned seem like brothers as well as father-son, and their competition for Jane has an aspect of sibling rivalry. When Jane reads to her unborn child and Ned listens in, he's the adult that Jane's baby will one day become, and she's the mom that Ned lost. 

Like Anderson's second and third features, The Life Aquatic was shot in CinemaScope, a super-wide rectangular format created to envelop the viewer. In the age of home video, 'Scope is more often used for action movies, science fiction films and historical epics, not comedies. But here, Anderson and cinematographer Robert Yeoman (who shot the director's previous films) manage to have it both ways. The framing is at once spectacular and intimate, elevating characters to heroic scale in close-ups and taking them down a peg in wide shots that turn them into flyspecks. More often than not, Anderson plants people and objects dead center in the frame, surrounded by acres of negative space, pinning them to their environments like butterflies behind glass.  When the camera moves, the shot often starts with one perfectly composed, perfectly balanced, color-coordinated composition and ends with another. It's as if the film is continually trying to get a handle on these people even as they try to get a handle on themselves. 

Among other things, the film is about living life as it happens, appreciating whoever you are and whoever you're with rather than constantly obsessing about the past and future. As Steve tells Eleanor, speaking words he doesn't yet recognize as wisdom, "Nobody knows what's going to happen. And then we film it. That's the whole concept." Steve is constantly trying to turn his life into a narrative with a clear direction and satisfying outcome, but his efforts are as forced as the cornball voice-overs in his partly staged "documentaries" and the strained ad-libs he and Ned devise on that jellyfish beach. Steve is a man who likes to be in control of everything even though he can't control much. His mission to kill the Jaguar Shark is the ultimate act of hubris: he wants nothing less than to track and kill Death and re-assert autonomy over his life. In time he'll learn this isn't possible. 

Matt Zoller Seitz

Matt Zoller Seitz is the Editor at Large of RogerEbert.com, TV critic for New York Magazine and Vulture.com, and a finalist for the Pulitzer Prize in criticism.

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