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 effect
relationships within the water based ecosystems. Without a conscious effort to
rehabilitate our water systems many rivers and lakes are doomed. We have to look after
this precious resource. Fortunately many new controls and clean up programs have been
Rivers are being devastated due to physical and ecological transformation. This
decrease in the quality of river and water bodies results from human activities and
processes. The ecosystems are changing rapidly. It is necessary to maintain a
consistent balance in these ecosystems. Imbalances are occurring with nutrient levels,
water temperature, water level, and sedimentation. "The stream then carries more
sediment and becomes wider, shallower, and warmer, making the water unfit for many
vital organisms." (Stevens, New York Times, Jan. 26, 1993)
The activities affecting the streams are as diverse as the areas in which streams
are being affected. Dams are capable of destroying total ecosystems. They affect
water levels, and thus affect water temperature. Changes in river temperature can
destroy total population of organisms. In addition they affect nutrient levels by
cutting them off, not allowing them to flow down stream. Salmon runs often fall prey
to the concrete monsters. Although this is often bypassed with salmon elevators.
Development of land often results in the straightening, channeling, and diversion
of the rivers and streams. Many rivers and streams have simply dried up most of the
year, and some never make it all the way to the ocean. This can be devastating to the
wide variety of species, and decimate niches and ecosystems lowering the biologicalÔ h) 0*0*0*°° Ô diversity. Development is often detrimental to river bank vegetation. ...