Water Degradation Essay, Research Paper
Water Degradation Based on the article: River Life Through U.S. Broadly Degraded. By William K. Stevens, Jan. 26, 93 Society has been presented with a broad spectrum of cause and effectrelationships within the water based ecosystems. Without a conscious effort torehabilitate our water systems many rivers and lakes are doomed. We have to look afterthis precious resource. Fortunately many new controls and clean up programs have beenintroduced. Rivers are being devastated due to physical and ecological transformation. Thisdecrease in the quality of river and water bodies results from human activities andprocesses. The ecosystems are changing rapidly. It is necessary to maintain aconsistent balance in these ecosystems. Imbalances are occurring with nutrient levels,water temperature, water level, and sedimentation. “The stream then carries moresediment and becomes wider, shallower, and warmer, making the water unfit for manyvital organisms.” (Stevens, New York Times, Jan. 26, 1993) The activities affecting the streams are as diverse as the areas in which streamsare being affected. Dams are capable of destroying total ecosystems. They affectwater levels, and thus affect water temperature. Changes in river temperature candestroy total population of organisms. In addition they affect nutrient levels bycutting them off, not allowing them to flow down stream. Salmon runs often fall preyto the concrete monsters. Although this is often bypassed with salmon elevators.Development of land often results in the straightening, channeling, and diversionof the rivers and streams. Many rivers and streams have simply dried up most of theyear, and some never make it all the way to the ocean. This can be devastating to thewide variety of species, and decimate niches and ecosystems lowering the biological+ h) 0*0*0*. . + diversity. Development is often detrimental to river bank vegetation. This allowswater to run off too quickly, thus reducing the water holding capacity of the land, andadding to sedimentation. Channeling and diversion can also be found in agriculture and farming practices.In addition chemical fertilizer and animal waste products run off causes an overabundance of nutrients being added to the water disrupting the delicate balances.Plowing and other practices leave soil victim to erosion which adds to thesedimentation of the river. Forestry is also a major cause of stream sedimentation. When the plant materialis removed the soil surface it is left very susceptible to erosion. This produces a lotof excess sedimentation over a long period of time. After an area is cleared thechemical balances are affected as well. “In particular, Ranberg and colleagues provedthat alkalinity increased when forest land was converted into agricultural land andacidification occurred when practices were abandoned.” (Charles, Nature, April 29,93) This clearly shows how the lake chemistry is affected by forestry and agriculture.Urban and suburban areas are also to blame. We continuously remove water from
our water ways for use, and replace it with wastes. This leads to nutrification andgeneral deterioration of the water. “Nationwide, there are 2,100 health advisories forfish contaminated by toxic chemicals, according to a 1991 National Academy of Sciencesreport, Seafood Safety.” (Marx, EPA Journal, Sept-Oct, 92) Heated effluent releasedinto river ecosystems are often detrimental. Emissions affect lake and riveracidification and therefore the ability to support aquatic organisms. The effects ofacid rain take a heavy toll on ecosystems whether they are water based or not. Another problem the river ecosystems are facing are exotic species. Somespecies are just naturally occurring incidence, others are human introduced. “Theyhave significantly reduced biological diversity through predation, alteration of habitat,introduction of diseases or parasites and interbreeding with native organisms.”(Stevens, New York Times, Jan. 26, 93) This shows the effects of introducing a foreignspecies to an established habitat. There are a number of factors affecting our riversand ecosystems. Fortunately some conscious effort is being made to preserve thisvaluable resource. These include saving the headwaters of major rivers, replantingriver banks, and government co operative water regulation at dams. An example of the attempts to help our current water situation is Chesapeake Bay where local governments have agreed to reduce the amount of nutrients being released by 40% before the year two thousand. Another form of preservation is the liming of water bodies rivers and entirewatersheds. Liming is the chemical neutralization of acidic waters. By liming theentire watershed, the treatment can last five to ten years. “Harvey Olem saysresearchers have estimated that half the U.S. surface waters acidified by air pollutants will eventually recover under the emissions control strategies most likely to emerge from strengthened Clean Air Act regulations. “The other half will remainacidic,” he observes. And for them “liming may be an option a tool for restoring theirfisheries.”" (Raloff, Science News, Feb 24, 1990) A lot of common practices must soon come to a halt. Obviously we are putting a veryheavy burden on our waterways. The effects of this are very clear. In order to dealwith these problems we must begin at the root of the problem. We must reduce ourwastes and find alternate means for disposal. We must cut back on emissions. Manythings are being done, and acts are being passed. The public population is starting totake it upon themselves to care for their river systems. Fortunately rivers are able,for the most part, to rebuild themselves once the inhibiting factors are removed. BIBLIOGRAPHYDonald Charles, “Acid Rain Not Only To Blame,” + +Nature,- – April 29, 93, P. 784Janet Raloff, “Lime for Your Drink?,” + +Science News,- – February 24, 90, P. 127Wesley Marx, ” Great Waterbodies at a Watershed,” + +EPA Journal- -, September October,92, P. 45-48William K. Stevens “River Life Through U.S. Broadly Degraded,” + + New York Times,- – January26, 93.
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