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|What is an Estuary? > Climate > Geology > Surface Water > Ground Water > Aquatic Habitat > Upland Habitat > Ecological Processes > Animals and Plants > Socioeconomic Values > Human Impacts and Pollution > Where does Your water come from? > Management Issues > Protecting YOUR Watershed|
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|Management Issues > Sediment Pollution > Chemical and Waste > Disease Pollution|
You can tell when erosion has occurred because you will see bare, exposed ground. Streams and riverbanks erode readily as flowing water wears away their sides and bottoms.
Agriculture, development (building houses and businesses), and dredging (digging channels in shallow water) are major contributors to erosion. These practices speed up erosion by removing the grass and plants that cover the soil and disturbing sediment.
Certain farming practices lead to erosion. Clearing land to plant crops exposes bare soil to wind and rain. When hillsides are farmed, rain readily washes soil downhill. And, when windbreaks are not put up, soil is blown away. Another agricultural problem is overgrazing. When grazing animals are crowded, they may eat vegetation down to the ground, exposing bare soil.
land for development leads to erosion. Soil is exposed during the process
of building homes, businesses, and parking lots. This loose soil gets
blown and washed across pavement and fields. Eventually it ends up in
Although these practices contribute greatly to erosion, it is important to note that careful planning can reduce erosion. To learn more about land-clearing practices that do a better job at containing sediment, see Protecting our watershed: What YOU can do to help.
Excess sediment causes many problems in an estuary. It covers up algae and detritus, two very important food sources. It makes the river bottom mushy, so that oysters and clams cannot attach and live there. Excess sediment also covers fish eggs that are laid in gravel beds.
When excess sediment harms detritus, algae, oysters and fish, all the other organisms in the estuary are affected too. Animals that eat algae and detritus, such as snails, fiddler crabs, shrimp, clams and worms, no longer have a food source. When these herbivorous animals cannot survive, the animals that eat them no longer have a food source. Carnivorous striped bass, starfish, raccoons and blue crabs no longer have anything to eat. And when these animals cannot survive, wading birds, such as great blue herons, no longer have anything to eat.
In addition to losing our coastal treasures, we also lose potential income. People that fish and harvest oysters and shrimp may go out of business. It is estimated that two-thirds (2/3) of all commercial fish spend some part of their life cycle in an estuary.
Pollution is a difficult problem because it is produced as a by-product of goods and services that are valuable to us. The good news is that there are many things we each can do (yes, Y?U!) to help solve our problem. To learn more about reducing your impact on the environment, see Protecting our watershed: What YOU can do to help.
we all live downstream ? in addition to local pollution, our water contains
pollutants from people living upstream. And, of course, our pollution
affects the water of people living downstream from us.