title: Stimulating nitrate removal processes of restored wetlands.
abstract: The environmental and health effects caused by nitrate contamination of aquatic systems are a serious problem throughout the world. A strategy proposed to address nitrate pollution is the restoration of wetlands. However, although natural wetlands often remove nitrate via high rates of denitrification, wetlands restored for water quality functions often fall below expectations. This may be in part because key drivers for denitrification, in particular soil carbon, are slow to develop in restored wetlands. We added organic soil amendments that range along a gradient of carbon lability to four newly restored wetlands in western New York to investigate the effect of carbon additions on denitrification and other processes of the nitrogen cycle. Soil carbon increased by 12.67-63.30% with the use of soil amendments (p ≤ 0.0001). Soil nitrate, the carbon to nitrogen ratio, and microbial biomass nitrogen were the most significant predictors of denitrification potential. Denitrification potential, potential net nitrogen nitrification and mineralization, and soil nitrate and ammonium, were highest in topsoil-amended plots, with increases in denitrification potential of 161.27% over control plots. While amendment with topsoil more than doubled several key nitrogen cycling processes, more research is required to determine what type and level of amendment application are most effective for stimulating removal of exogenous nitrate and meeting functional goals within an acceptable time frame.
authors.affiliation: Department of Environmental Studies, Mount Holyoke College , South Hadley, Massachusetts 01075, United States.
authors.forename: Kate A
authors.initials: KA
authors.lastname: Ballantine
authors.forename: Peter M
authors.initials: PM
authors.lastname: Groffman
authors.forename: Johannes
authors.initials: J
authors.lastname: Lehmann
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Schneider
mesh_terms: D064751:Ammonium Compounds / Q000032:analysis; D018533:Biomass; D002244:Carbon / Q000032:analysis; D058440:Denitrification; D062070:Hydrology; D009518:New York; D009566:Nitrates / Q000302:isolation & purification*; D009584:Nitrogen / Q000032:analysis; D058458:Nitrogen Cycle; D012987:Soil / Q000737:chemistry; D014867:Water; D053833:Wetlands
chemical_list: D064751:Ammonium Compounds; D009566:Nitrates; D012987:Soil; D014867:Water; D002244:Carbon; D009584:Nitrogen