Nitrogen as an Ecological Function
What is nitrogen?
Nitrogen is a naturally occurring element (found in the atmosphere
and organic compounds) that occurs in several forms: gaseous nitrogen, ammonium,
nitrate, and nitrite. In discussing the ecosystem processes and functions
of shorelines, the focus is on nitrate and ammonium.
Why is nitrogen important?
Nitrogen is the biological limiting nutrient in marine systems, generally
by being the least available for marine plants and algae. It is similar to
phosphorus in freshwater in that when there is too much or too little it can
change how an ecosystem functions.
What affects the movement or amount of nitrogen?
Altering wetlands and headwater streams through channelizing or filling can
affect the movement of nitrogen.
Nitrogen moves through the watershed in these key areas:
- depressional wetlands
- headwater streams, and
- soil erosion.
Nitrogen can be increased through:
- leakage of septic systems;
- agricultural and residential impacts such as the application of manure and fertilizers or poor manure management; and
- clearing areas without soil stabilization or without replanting native species. (Some non-native invasive species can increase the amount of nitrogen along shorelines.)
References: Stanley
et al 2005; and Schlesinger
1997 (Acrobat pdf files).
Related Information
- King County Streams Water Quality Data
- Shoreline Practices for a Healthy Lake, River or Creek
- King County Wetlands
