Nitrogen cycling wetlands

Ammonia loss through volatilization to the atmosphere is a complex process mediated by a combination of physical, chemical, and biological factors. The exchange of ammonia between water column, soils, and the atmosphere plays an important role in wetland nitrogen cycle. However, the significance of this process is not well established. 

FIGURE 11.1 Sulfur cycling in wetlands is closely associated with carbon and nitrogen cycling. (From Krairapanond et al., 1992.)... 

Francis, C. A., J. M. Beman, and M. M. M. Kuypers. 2007. New processes and players in the nitrogen cycle the microbial ecology of anaerobic and archaeal ammonia oxidation. Int. Soc. Microbial Ecol. J. 1 19-27. Gutknecht, J. L. M. and R. M. Goodman. 2006. Linking soil process and microbial ecology in freshwater wetland ecosystems. Plant Soil 289 17-34. 

Discnss the biogeochemical cycle of nitrogen in mixed ecosystems. Stress your attention on wetlands and upland landscapes. 

Wetlands and aquatic systems are recipients of phosphorus loads from upland systems. Increased loading of phosphorus to a system can cause nitrogen limitations. The phosphorus enrichment of P-limited systems leads to eutrophication and ecosystem stress. The phosphorus cycle does not have a significant gaseous loss mechanism. Thus, most of the added P accumulates in the systems. 

Nutrients incorporated into herbaceous material are deposited on soil surface or exported from the wetland as detritus or dissolved nutrients released by decaying vegetation. Air-water exchange also plays an important role in biogeochemical cycling of carbon, nitrogen, and sulfur. Wetlands emit methane, carbon dioxide, nitrous oxide, and reduced sulfur gases to the atmosphere. 

---