![[Dept. of Animal Sciences]](../../images/jcnerr.gif "[Dept. of Animal Sciences]"){kind=small}
Nitrogen under two scenarios.
Here we have modelled nitrogen runoff under the two scenarios.
What's the difference?
The amount of nitrogen runoff into the water system (pounds per year) is three times greater under a traditional zoning buildout compared to the alternative zoning.
Why this difference?
Nitrogen loading is primarily the result of non-point source pollution or runoff from lawn fertilizers and agricultural industries. An increase of Impervious Surface can also increase the amount of nitrogen in the water supply as more particles are washed into stream beds instead of being filtered out as water moves through soil layers.
What will it mean?
An increase of nitrogen can cause an increase of primary production and oxygen depletion within water bodies (lakes, streams, rivers, and estuaries). If levels are high enough this can cause an ecological shift of community structure changing the types and population of local flora and fauna.
Let's take a look the impact of lead. 