Nitrogen mineralization, nitrification and denitrification in upland and wetland ecosystems

Measuring nitrification, denitrification, and related biomarkers in terrestrial geothermal ecosystems.

Research on the nitrogen biogeochemical cycle in terrestrial geothermal ecosystems has recently been energized by the discovery of thermophilic ammonia-oxidizing archaea (AOA). This chapter describes methods that have been used for measuring nitrification and denitrification in hot spring environments, including isotope pool dilution and tracer approaches, and the acetylene block approach. The ...

Nitrification and denitrification in humid tropical ecosystems: potential controls on nitrogen retention

1 Nitrification is an important microbial process in humid tropical ecosystems because of its effects on potentials for nitrogen loss via nitrate leaching and denitrification and on the hydrogen ion cycle. Nitrification rates in humid tropical soils vary markedly among different forest types but in general appear to increase following disturbance. Proximal controls on nitrifiers include ammoniu...

Study on Nitrification and Denitrification of High Nitrogen and COD Load Wastewater in Moving Bed Biofilm Reactor

Regulation of nitrogen mineralization and nitrification in Southern Appalachian ecosystems: Separating the relative importance of biotic vs. abiotic controls

Long-term measurements of soil nitrogen (N) transformations along an environmental gradient within the Coweeta Hydrologic Laboratory basin in western North Carolina showed a strong seasonal pattern and suggested that vegetation community typethrough its influence on soil properties-was an important regulating factor. Our objective was to determine the relative effects of biotic vs. abiotic fact...

Nitrous Oxide Nitrification and Denitrification

The isotopic signatures of N and O in N2O emitted from tropical soils vary both spatially and temporally, leading to large uncertainty in the overall tropical source signature and thereby limiting the utility of isotopes in constraining the global N2O budget. Determining the reasons for spatial and temporal variations in isotope signatures requires that we know the isotope enrichment factors fo...