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Discuss how humans have impacted aquatic systems, and how these actions have affected aquatic resource availability.Human activities have put a lot of pressure on aquatic systems and have had negative effects on them. Coastal habitats have been reported to be disappearing at rates much higher than tropical rainforest loss. Mangrove forests are being lost in many subtropical and tropical countries. Moreover, coastal wetland destruction has become increasingly common in industrial countries. Coastal sea-grass beds, which function as “nurseries” for shellfish and other fish, are important for feeding these small fish and thus larger fish down the road in the food chain. A 2009 studied has showed than nearly 60 percent of sea-grass meadows around the world have been degraded or destroyed. Not to mention climate change has lead to increasing sea levels and the destruction of coral reefs and swamps, further threatening fish habitats and their resources. Trawler fishing boards have additionally damaged sea-bottom habitats so much that their destruction exceeds that of forests clear-cut on a yearly basis. This large pressure on aquatic habitats and a species can clearly be seen in coral reefs, which are being threatened by ocean acidification resulting from increased levels of CO2 emitted by human actions, increasing shore development, and pollution. This habitat destruction has also been seen in freshwater aquatic zones, where excessive water withdrawal for irritation and dam building have disrupted freshwater diversity, habitats, and negatively affected water flow. With all this destruction, resources have become much more scarce for fish and other species living in aquatic systems. As such, these species are overburdened and can potentially suffer, further perpetuating a cycle in which humans that rely on these fish and these aquatic systems for resources also suffer.Describe using specifics some of the threats to biodiversity in Lake VictoriaFor the past two decades, the biodiversity in Lake Victoria has been in trouble. Until around the early 1980s, the lake had 500 species of fish found nowhere else. 80% of these species were small fish called cichlids, which feed on mainly detritus, algae, and zooplankton. Since 1980, many of these cichlids have become extinct and remain in trouble. First off, the large increase in the population of Nile perch has led to a loss in aquatic biodiversity in Lake Victoria. This large and predatory fish was brought into the lake in the 1950s and 1960s as a way to increase the exportation of fish from the lake to European countries, despite the fact that biologists warned that Nile perch would eliminate many defenseless native fish species. Social and ecological effects also ensued. The incoming perch-fishing industry developed and put many small-scale fishers and vendors out of business, further leading to regional poverty and malnutrition for these fishermen. Furthermore, many people used wood-burning smokers to preserve the flesh of the perch; this wood of course, was taken from local forests for firewood and depleted the forests. Lastly, frequent and thick algae blooms led to many deaths of fish in Lake Victoria. Very common in the 1980s, these blooms were fed by nutrient runoff from nearby forms and deforested land in addition to spills of untreated sewage. Not to mention, the invasion in the late 1980s of water hyacinth also led to a biodiversity threat. This plant spread and covered large parts of the lake, thus blocking sunlight, depriving fish of oxygen and plankton, and reducing the diversity of critical aquatic plants.Describe problems associated with marine environment protection. Discuss the roles of legislation, regulation, and economic pressures.Marine environmental protection is oftentimes a very complicated task that is nuanced with issues in legislation, regulation, and other economic pressures. Marine environmental protection is specifically difficult for several reasons. First, the human ecological footprint and fishprint are rapidly expanding and it is often tough to monitor their impacts. Secondly, the damage in oceans and other bodies of water is not visible to most people. Thirdly, many people incorrectly recognize the seas as a resource that can absorb an infinite amount of pollution and waste while still producing enough seafood. Fourthly, most of the world’s oceans lie outside the legal range of any country. As a result, we have a similar “tragedy of the commons” scenario and overexploitation is common. The regulatory approach is a way to protect and sustain marine environmental biodiversity. Nation and international laws to protect marine species include the 1975 Convention on International Trade in Endangered Species (CITES), the 1979 Global Treaty on Migratory Species, the U.S. Marine Mammal Protection Act of 1972, the U.S. Endangered Species Act of 1973, the U.S. Whale Conservation and Protection Act of 1976, and the 1995 International Convention on Biological Diversity. The U.S. Endangered Species Act and a few other international agreements have been used to protect and identify marine species like whales, sea lions, and sea turtles that are threatened. However, with all international agreements, it can be hard to get compliance across many different nations. The International Whaling Commision (IWC) moratorium on commercial whaling is a particular aspect of legislation that has had a tough time in compliance. Countries like Japan continue to hunt and kill whales for their resources, while countries like the U.S. are against it (TV show “Whale Wars” depicts this). Economic incentives are also used to help protect endangered aquatic species. In 2004, the World Wildlife Fund showed how sea turtles have more worth to local communities alive than dead since sea turtle tourism brings in three times more money vs. sea turtle products like meat, leather, and eggs.Regulation of p. 266. Yet there can also be a negative sign of economic pressures. Economic pressure of tourism and fishing can also lead to overfishing. Take, for example, Key West were many fishermen venture in the summer months to fish. While regulations and limitations are available on how many fish one can keep, an increased number of tourists who fish can serve to stimulate the local economy, but also potentially ruin aquatic diversity by overfishing or disrupting coral reefs. At the same time, marine sanctuaries protect ecosystems and species and can be enforced by laws such as the Law of the Sea Treaty. Today, government subsidies have been shown to encourage overfishing, resulting in too many boats chasing too few fish. Bottom up pressure from consumers demanding sustainable food is a way to encourage more responsible fishing. Furthermore, labeling of fresh and frozen seafood to inform consumers about where they were caught is also important. Certification of sustainably caught seafood (Marine Stewardship Council in London) is also important in preserving aquatic diversity. Distinguish between coastal and inland wetlands. Describe the ecological functions performed by wetlands. Describe environmental problems associated with coastal and inland wetlands.Coastal wetlands are coastal land areas covered with water for all or part of the year and include river mouths, inlets, bays, sounds, and coastal marshes. On the other hand, inland wetlands, are lands away from the coast and include swamps, marshes, or bags covered all or part of the time with freshwater. Both types of these wetlands are important reservoirs for aquatic biodiversity and provide important economic and ecological impact. For many years, individuals have drained, filled in, or covered these wetlands to create croplands, rice fields, accommodate expanding cities and their suburbs, and for the purpose of building roads. Moreover, wetlands have been destroyed as a way to get oil and natural gas from them, further eliminating critical breedings grounds for insects that cause severe diseases like malaria. Dams and levees on rivers are also causing wetlands to disappear because they are interfering with the deposition of sediments that would naturally replace those washed out to see. The worst thing is that coastal wetlands will most likely be under water sooner or later as a result of global warming and rising sea levels. Thus, this could really have a negative impact on aquatic biodiversity in these wetlands, including commercially important fish and shellfish as well as waterfowl and other migratory birds. Not to mention, these rising sea levels will also reduce many other ecological and economic services these wetlands provide.Detail 4 industrial fishing methods. For each method briefly describe ecological collateral damage that results from their use.Bottom TrawlingBycatchExplosives (?) (This may help) the history and development of the Columbia River Basin. Summarize the lessons learned from the problems that were generated and the plans to address those problems.The Columbia River Basin is an example of biodiversity loss. The Columbia River runs through western Canada and the Northwest U.S. The Columbia River has many dams, which generate hydroelectric power and also supplies water for major urban areas and other irrigation projects. While the Columbia River dam system benefitted many individuals, it had a negative impact on wild salmon populations. Dams interrupt the life cycle of these salmon by interfering with the migration of young fish downstream and by also blocking the return upstream of other mature fish attempting to spawn. Since the 119 dams of the Columbia River were built, the Pacific salmon population dropped by 94% and now 9 of the Pacific Northwest salmon species are either threatened or endangered. Since 1980, the U.S. government has spent 3 billion dollars to protect the salmon, but efforts have been mainly ineffective. Furthermore, in the lower parts of the Snake River in Washington State, conservationists, Native Americans, and commercial salmon fishers want the government to remove hydroelectric dams to help restore salmon spawning. However, this has been met with resistance rom aluminum workers and barge operators who argue that this would reduce irrigation and hurt the local economies. All of this provides an important lesson in the preservation of freshwater ecosystems that can be protected by law, economic incentives, and other restoration efforts. In the case of the Snake River, compromise may be necessary in restoring these dams. Some politicians have even argued for protecting all remaining free-flowing rivers. In 1968, Congress passed the National Wild and Scenic Rivers Act to establish the protection of rivers. And in 2009, U.S. congress passed a law that increased the length of wild and scenic rivers by half. Certainly all these issues involve important discussion and dialogue. While not everyone will win, protecting the environment can have important long-term benefits.

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