During the last century, the region has experienced a change in land use, since urban, suburban, and agricultural areas are the natural ecosystem of the region. This has increased the number of nutrients and sediment entering rivers and streams and has contributed to poor water quality that affects aquatic life. Excess nutrients, for example, fuel the growth of algae blooms that create "dead zones" with little oxygen. Stress-related to poor water quality can do considerable damage to the entire ecosystem.
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