|
The major nonpoint sources of pollutants are sediments, nutrients and toxins.
Sediments
Sediments are particles of soil that are washed into our streams, lakes and wetlands by melting snow and rain. This is known
as erosion. Increased sediments may significantly alter the ecology and water quality of our water resources.
Nutrients
Nitrogen and phosphorus are the most common nonpoint source pollutants coming from many sources. These nutrients are present
in soils, fertilizer, manure, sewage, and litter. If excessive nutrients are present in water, lakes, streams and wetlands
may become eutrophic (low oxygen) and cause fish kills.
Toxins
Chemicals and metals have many positive uses in our society, but many of them are toxic at certain concentrations and can
harm aquatic organisms, fish, and other animals associated with streams, lakes and wetlands. These substances are consumed
by microorganisms and the concentration of these substance will increase with each level of the food chain. By the time fish
are caught by you or I, it may not be safe to eat.
|
 |
|
NPS POLLUTION OF CERTAIN LAND USES
(lbs/acres/year)
|
|
|
|
|
 |
|
|
Land Use
|
Sediment
|
Phosphorus
|
Nitrogen
|
|
Forest
|
200
|
0.20
|
2.20
|
|
Pasture
|
350
|
0.30
|
4.40
|
|
Cropland
|
1,400
|
0.50
|
9.80
|
|
Barnyard
|
1,750
|
0.80
|
4.60
|
|
Lawn
|
400
|
1.20
|
7.50
|
|
Golf Course
|
1,300
|
3.00
|
19.40
|
|
Urban Land
|
570
|
1.30
|
9.00
|
|
|
|
|
|
|
|
|
|
|
|
