Comparing nutrient export from first, second and third order watersheds in the South Carolina Atlantic coastal plain

Monitoring of stream water chemistry in forested watersheds provides information to environmental scientists that relate management operations to hydrologic and biogeochemical processes. We used data for the first order watershed, WS80, and second order watershed, WS79, at Santee Experimental Forest. We also used data from a third order watershed, WS78, to identify the differences in temporal changes of stream water chemistry from 2006 to 2012. Phosphate concentrations for WS80 and WS79 decreased from 2006 to 2012. Most of the nitrogen (N) component was dominated by organic N and the watershed that registered highest organic N also registered highest total N concentration. Phosphate and N concentrations for all watersheds varied with rainfall received in the area. The annual mean pH of all watersheds significantly increased with stream conductivity (p < 0.05). The differences in fluctuations of observed annual stream water nutrient concentrations for all watersheds may provide a basis for nutrient availability for aquatic responses.