Marine Biome: Negative Impacts And Their Causes

Human activities have had a detrimental impact on marine life and habitats through overfishing, habitat loss, the introduction of invasive species, ocean pollution, ocean acidification, and warming. These impacts have far-reaching consequences for marine ecosystems, food webs, and the biodiversity and survival of marine life forms. The ocean, the world's largest ecosystem, is home to countless species, and human actions are putting this delicate balance at risk. From coastal ecosystems to the open ocean, the negative effects of human activities are evident, with overfishing, pollution, and climate change being key drivers of ecological disruption.

Oil spills

The magnitude of harm caused by oil spills varies depending on factors such as the amount of exposure, the pathway of exposure, the age and health of affected animals, and the type of synthetic chemicals used in the cleanup process. While natural processes like wind, waves, and microbes can help disperse and break down oil, the impact on marine life is often severe and long-lasting.

To address oil spills, specialists and veterinarians are trained to clean and rehabilitate affected wildlife, returning them to their natural environment. During cleanup efforts, various tools and techniques are employed, including skimmers, booms, and controlled burning. However, preventing oil spills in the first place is crucial to protecting sensitive marine areas and the diverse life they support.

Overfishing

Ecologically, overfishing disrupts the delicate balance of marine ecosystems. It can alter food webs and lead to the loss of vital habitats such as coral reefs, seagrass meadows, and kelp forests. These ecosystems are essential for maintaining marine biodiversity, providing seafood, and protecting coasts. Overfishing of large predators can cause a shift in the food web structure, leading to a decline in prey species and the proliferation of algae. This, in turn, can smother and reduce seagrass populations, further disrupting the ecosystem.

The impact of overfishing extends beyond the marine environment and affects the lives and livelihoods of millions of people worldwide. Fishing is the principal livelihood for many, and billions depend on fish as a source of protein. Overfishing can lead to decreased food and economic security, particularly in developing coastal communities. It can also have far-reaching effects on industries such as seafood trading and tourism, which are closely linked to the health of marine ecosystems.

To address overfishing, it is crucial to implement sustainable fishing practices and improve fisheries management. This includes reforming government policies, reducing illegal fishing, and eliminating harmful fishing subsidies. Additionally, creating and expanding marine protected areas can help safeguard key fish species and support the livelihoods of coastal communities. By taking these steps, we can work towards conserving marine ecosystems, sustaining livelihoods, and ensuring food security for the future.

Furthermore, overfishing can have a cascading effect on marine ecosystems, leading to a decline in species diversity and altering the structure of food webs. Removing large predators from the ecosystem can result in an increase in the population of their prey, which then affects the species that they feed on, and so on. This disruption can have far-reaching consequences for the entire marine biome, affecting not only fish populations but also other marine organisms and the overall health of the ecosystem.

Plastic pollution

The Sources of Plastic Pollution in the Marine Biome

The Impact on Marine Life and Ecosystems

The Health Hazards of Plastic Pollution

Microplastics, tiny plastic particles, have infiltrated various aspects of our lives, from drinking water and salt to beer and soil-grown vegetables. These microplastics can have detrimental effects on human health. They can affect the body's endocrine system, leading to developmental, neurological, reproductive, and immune disorders. Moreover, toxic contaminants often accumulate on plastic surfaces, and consuming seafood exposed to these toxins can be harmful.

The Economic Impact

The economic costs of plastic pollution in the ocean are significant, estimated to be between $6-19 billion USD annually. This includes impacts on tourism, fisheries, and aquaculture, as well as the costs of cleanup operations. Additionally, plastic production contributes to climate change, as it is derived from fossil fuels, and incinerating plastic waste releases carbon dioxide and methane, exacerbating global warming.

Addressing the Problem: Prevention and Solutions

Preventing plastic waste from entering rivers and seas is crucial, as retrieving plastic from the ocean, especially microplastics, is extremely challenging. This can be achieved through improved waste management systems, increased recycling, and reduced use of disposable packaging and single-use plastics. Individual actions, such as reducing plastic consumption, supporting relevant legislation, and participating in clean-up efforts, are vital. Additionally, supporting research and organizations dedicated to combating plastic pollution is essential to develop effective solutions.

Eutrophication

The process of eutrophication begins with an overabundance of nutrients, such as nitrogen and phosphorus, in the water. These nutrients act as fertilisers, leading to excessive growth of plants and algae, including harmful algal blooms. This overgrowth blocks sunlight from reaching underwater plants, causing their death. As the excess algae and plant matter eventually decompose, they produce large amounts of carbon dioxide, which lowers the pH of seawater, a process known as ocean acidification.

Ocean acidification has several detrimental consequences. It slows the growth of fish and shellfish, prevents shell formation in bivalve mollusks such as oysters, clams, and scallops, and reduces essential fish habitats. This leads to a decline in commercial and recreational fisheries, resulting in smaller harvests and more expensive seafood. Eutrophication also disrupts the balance of the marine ecosystem, affecting the survival of various organisms, including fish and other wildlife that depend on oxygen-rich waters.

The economic impacts of eutrophication can be significant. For example, commercial shellfisheries in Long Island Sound have lost millions of dollars annually due to eutrophication. Additionally, there are environmental concerns, as eutrophication contributes to the degradation of water quality, destruction of economically important fisheries, and public health risks.

To address eutrophication, various techniques have been employed, including chemical, physical, and biological methods. Chemical coagulants such as lime, magnesium sulphate, and ferric sulphate have been effective in removing nitrate and phosphate from wastewater. Biological techniques, such as wetland treatment, have also shown promising results in removing excess nutrients. However, the success of these techniques depends on various factors, and it is essential to develop effective long-term solutions to mitigate the negative impacts of eutrophication on the marine biome.

Ocean acidification

The process of ocean acidification is simple chemistry. When carbon dioxide dissolves in seawater, it forms carbonic acid, which releases hydrogen ions. Seawater with more hydrogen ions is more acidic and has a lower pH. The pH of the ocean has decreased by about 25% since before the Industrial Revolution, a greater change than at any other time in the last two million years.

This change in ocean chemistry negatively affects marine life. Many ocean plants and animals build shells and skeletons out of calcium carbonate, and increased acidity slows the growth of these structures. In severe cases, it can dissolve structures faster than they can form. Organisms such as mussels, sea urchins, and crabs have been observed to start dissolving their protective shells to counter elevated acidity in their body fluids.

The building of skeletons in marine creatures is particularly sensitive to acidity. One of the molecules that hydrogen ions bond with is carbonate, a key component of calcium carbonate shells. Shell-building organisms such as corals and oysters combine a calcium ion with carbonate from the seawater to create their shells. However, hydrogen ions have a greater attraction to carbonate than calcium, and when they bond, they form bicarbonate, which shell-building organisms cannot use. This makes it harder for these organisms to build and maintain their shells, and they may have to spend more energy doing so, impairing their overall health and ability to reproduce.

Some species may be able to adapt to the changing conditions. Crustaceans, for example, have been found to grow stronger shells under higher acidity. Some plants and algae may also thrive under more acidic conditions, as they use carbon dioxide to make energy. However, coralline algae, which help cement coral reefs, do not fare as well under increased acidity.

The effects of ocean acidification are expected to be dramatic and mostly negative, with the potential to decrease marine biodiversity on a large scale. While some organisms may survive or even thrive, others will struggle to adapt and may go extinct. This loss of biodiversity will also impact fisheries and aquaculture, threatening food security and economies related to the sea.

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