The Effects of Excessive Nitrogen and Phosphorus in Surface Waters of a Prairie Marsh

摘要

Use of natural wetlands as wastewater renovation sites requires knowledge of short- and long-term effects of nutrient enrichment on the ecosystem. Research was carried out to assess the impact of nitrogen (N) and phosphorus (P) enriched marsh waters on levels of N and P in interstitial water, and on emergent plant production and on decomposition. Ammonium nitrae and diammonium phosphate were applied to surface water of an Iowa praire marsh (Eagle Lake) in 1979 and 1980. Application in 1979 caused increases of ammonium-N (AN), nitrate-N, and phosphate-P (PP) in 15-cm interstitial water of 144, 291, and 47%, respectively. The results suggest decomposing below-ground litter is a continuous source of N under both fertilized and unfertilized conditions.