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Environmental Impact Of Fishing
The environmental impact of fishing includes issues such as the availability of fish, overfishing, fisheries, and fisheries management; as well as the impact of industrial fishing on other elements of the environment, such as bycatch. These issues are part of marine conservation, and are addressed in fisheries science programs. According to a 2019 FAO report, global production of fish, crustaceans, molluscs and other aquatic animals has continued to grow and reached 172.6 million tonnes in 2017, with an increase of 4.1 percent compared with 2016. There is a growing gap between the supply of fish and demand, due in part to world population growth. Fishing and pollution from fishing are the largest contributors to the decline in ocean health and water quality. Ghost nets, or nets abandoned in the ocean, are made of plastic and nylon and do not decompose, wreaking extreme havoc on the wildlife and ecosystems they interrupt. The ocean takes up 70% of the earth, so overfishing and h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fishing Down The Food Web
Fishing down the food web is the process whereby fisheries in a given ecosystem, "having depleted the large predatory fish on top of the food web, turn to increasingly smaller species, finally ending up with previously spurned small fish and invertebrates". The process was first demonstrated by the fisheries scientist Daniel Pauly and others in an article published in the journal ''Science'' in 1998.Pauly D, Christensen V, Dalsgaard J, Froese R and Torres F (1998"Fishing down marine food webs"''Science'', 279: 860-863. Large predator fish with higher trophic levels have been depleted in wild fisheries. As a result, the fishing industry has been systematically "fishing down the food web", targeting fish species at progressively decreasing trophic levels. The trophic level of a fish is the position it occupies on the food chain. The article establishes the importance of the mean trophic level of fisheries as a tool for measuring the health of ocean ecosystems. In 2000, the Conve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollution
Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants. Although environmental pollution can be caused by natural events, the word pollution generally implies that the contaminants have an anthropogenic source – that is, a source created by human activities. Pollution is often classed as point source or nonpoint source pollution. In 2015, pollution killed nine million people worldwide (one in six deaths). This remained unchanged in 2019, with little real progress against pollution being identifiable. Air pollution accounted for of these earlier deaths. Major forms of pollution include air pollution, light pollution, litter, noise pollution, plastic pollution, soil contamination, radioactiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pork
Pork is the culinary name for the meat of the domestic pig (''Sus domesticus''). It is the most commonly consumed meat worldwide, with evidence of pig husbandry dating back to 5000 BCE. Pork is eaten both freshly cooked and preserved; curing extends the shelf life of pork products. Ham, gammon, bacon, and sausage are examples of preserved pork. Charcuterie is the branch of cooking devoted to prepared meat products, many from pork. Pork is the most popular meat in the Western world, particularly in Central Europe. It is also very popular in East and Southeast Asia ( Mainland Southeast Asia, Philippines, Singapore, and East Timor). The meat is highly prized in Asian cuisines, especially in Mainland China, for its fat content and texture. Some religions and cultures prohibit pork consumption, notably Islam and Judaism. History Pigs were domesticated in Mesopotamia around 13,000 BC. Charcuterie is the branch of cooking devoted to prepared meat products such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aquaculture
Aquaculture (less commonly spelled aquiculture), also known as aquafarming, is the controlled cultivation ("farming") of aquatic organisms such as fish, crustaceans, mollusks, algae and other organisms of value such as aquatic plants (e.g. lotus). Aquaculture involves cultivating freshwater, brackish water and saltwater populations under controlled or semi-natural conditions, and can be contrasted with commercial fishing, which is the harvesting of wild fish. Mariculture, commonly known as marine farming, refers specifically to aquaculture practiced in seawater habitats and lagoons, opposed to in freshwater aquaculture. Pisciculture is a type of aquaculture that consists of fish farming to obtain fish products as food. Aquaculture can also be defined as the breeding, growing, and harvesting of fish and other aquatic plants, also known as farming in water. It is an environmental source of food and commercial product which help to improve healthier habitats and used to recon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trawling
Trawling is a method of fishing that involves pulling a fishing net through the water behind one or more boats. The net used for trawling is called a trawl. This principle requires netting bags which are towed through water to catch different species of fishes or sometimes targeted species. Trawls are often called towed gear or dragged gear. The boats that are used for trawling are called trawlers or draggers. Trawlers vary in size from small open boats with as little as 30 hp (22 kW) engines to large factory trawlers with over 10,000 hp (7.5 MW). Trawling can be carried out by one trawler or by two trawlers fishing cooperatively (pair trawling). Trawling can be contrasted with trolling. While trawling involves a net and is typically done for commercial usage, trolling instead involves a reed, rod and a bait or a lure and is typically done for recreational purposes. Trawling is also commonly used as a scientific sampling, or survey, method. Bottom vs. midwater trawling ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Recirculating Aquaculture System
Recirculating aquaculture systems (RAS) are used in home aquaria and for fish production where water exchange is limited and the use of biofiltration is required to reduce ammonia toxicity. Other types of filtration and environmental control are often also necessary to maintain clean water and provide a suitable habitat for fish. The main benefit of RAS is the ability to reduce the need for fresh, clean water while still maintaining a healthy environment for fish. To be operated economically commercial RAS must have high fish stocking densities, and many researchers are currently conducting studies to determine if RAS is a viable form of intensive aquaculture. RAS water treatment processes A series of treatment processes is utilized to maintain water quality in intensive fish farming operations. These steps are often done in order or sometimes in tandem. After leaving the vessel holding fish the water is first treated for solids before entering a biofilter to convert ammonia, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beef
Beef is the culinary name for meat from cattle (''Bos taurus''). In prehistoric times, humankind hunted aurochs and later domesticated them. Since that time, numerous breeds of cattle have been bred specifically for the quality or quantity of their meat. Today, beef is the third most widely consumed meat in the world, after pork and poultry. As of 2018, the United States, Brazil, and China were the largest producers of beef. Beef can be prepared in various ways; cuts are often used for steak, which can be cooked to varying degrees of doneness, while trimmings are often ground or minced, as found in most hamburgers. Beef contains protein, iron, and vitamin B12. Along with other kinds of red meat, high consumption is associated with an increased risk of colorectal cancer and coronary heart disease, especially when processed. Beef has a high environmental impact, being a primary driver of deforestation with the highest greenhouse gas emissions of any agricultural product. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greenhouse Gas Emissions
Greenhouse gas emissions from human activities strengthen the greenhouse effect, contributing to climate change. Most is carbon dioxide from burning fossil fuels: coal, oil, and natural gas. The largest emitters include coal in China and large oil and gas companies, many state-owned by OPEC and Russia. Human-caused emissions have increased atmospheric carbon dioxide by about 50% over pre-industrial levels. The growing levels of emissions have varied, but it was consistent among all greenhouse gases (GHG). Emissions in the 2010s averaged 56 billion tons a year, higher than ever before. Electricity generation and transport are major emitters; the largest single source, according to the United States Environmental Protection Agency, is transportation, accounting for 27% of all USA greenhouse gas emissions. Deforestation and other changes in land use also emit carbon dioxide and methane. The largest source of anthropogenic methane emissions is agriculture, closely followed by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecological Niche
In ecology, a niche is the match of a species to a specific environmental condition. Three variants of ecological niche are described by It describes how an organism or population responds to the distribution of resources and competitors (for example, by growing when resources are abundant, and when predators, parasites and pathogens are scarce) and how it in turn alters those same factors (for example, limiting access to resources by other organisms, acting as a food source for predators and a consumer of prey). "The type and number of variables comprising the dimensions of an environmental niche vary from one species to another ndthe relative importance of particular environmental variables for a species may vary according to the geographic and biotic contexts". See also Chapter 2: Concepts of niches, pp. 7 ''ff'' A Grinnellian niche is determined by the habitat in which a species lives and its accompanying behavioral adaptations. An Eltonian niche emphasizes that a spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trawling
Trawling is a method of fishing that involves pulling a fishing net through the water behind one or more boats. The net used for trawling is called a trawl. This principle requires netting bags which are towed through water to catch different species of fishes or sometimes targeted species. Trawls are often called towed gear or dragged gear. The boats that are used for trawling are called trawlers or draggers. Trawlers vary in size from small open boats with as little as 30 hp (22 kW) engines to large factory trawlers with over 10,000 hp (7.5 MW). Trawling can be carried out by one trawler or by two trawlers fishing cooperatively (pair trawling). Trawling can be contrasted with trolling. While trawling involves a net and is typically done for commercial usage, trolling instead involves a reed, rod and a bait or a lure and is typically done for recreational purposes. Trawling is also commonly used as a scientific sampling, or survey, method. Bottom vs. midwater trawling ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Washington Post
''The Washington Post'' (also known as the ''Post'' and, informally, ''WaPo'') is an American daily newspaper published in Washington, D.C. It is the most widely circulated newspaper within the Washington metropolitan area and has a large national audience. Daily broadsheet editions are printed for D.C., Maryland, and Virginia. The ''Post'' was founded in 1877. In its early years, it went through several owners and struggled both financially and editorially. Financier Eugene Meyer purchased it out of bankruptcy in 1933 and revived its health and reputation, work continued by his successors Katharine and Phil Graham (Meyer's daughter and son-in-law), who bought out several rival publications. The ''Post'' 1971 printing of the Pentagon Papers helped spur opposition to the Vietnam War. Subsequently, in the best-known episode in the newspaper's history, reporters Bob Woodward and Carl Bernstein led the American press's investigation into what became known as the Watergate scandal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bahamas
The Bahamas (), officially the Commonwealth of The Bahamas, is an island country within the Lucayan Archipelago of the West Indies in the Atlantic Ocean, North Atlantic. It takes up 97% of the Lucayan Archipelago's land area and is home to 88% of the archipelago's population. The archipelagic state consists of more than 3,000 islands, cays, and islets in the Atlantic Ocean, and is located north of Cuba and northwest of the island of Hispaniola (split between the Dominican Republic and Haiti) and the Turks and Caicos Islands, southeast of the U.S. state of Florida, and east of the Florida Keys. The capital is Nassau, Bahamas, Nassau on the island of New Providence. The Royal Bahamas Defence Force describes The Bahamas' territory as encompassing of ocean space. The Bahama Islands were inhabited by the Lucayan people, Lucayans, a branch of the Arawakan-Taino language, speaking Taíno, for many centuries. Christopher Columbus was the first European to see the islands, making hi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
