Premium
Denitrification Potential in Urban Riparian Zones
Author(s) -
Groffman Peter M.,
Crawford Marshall Kamau
Publication year - 2003
Publication title -
journal of environmental quality
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.888
H-Index - 171
eISSN - 1537-2537
pISSN - 0047-2425
DOI - 10.2134/jeq2003.1144
Subject(s) - riparian zone , environmental science , denitrification , surface runoff , hydrology (agriculture) , stormwater , wetland , nitrate , soil water , ecology , soil science , nitrogen , geology , chemistry , geotechnical engineering , organic chemistry , habitat , biology
Denitrification, the anaerobic microbial conversion of nitrate NO − 3 to nitrogen (N) gases, is an important process contributing to the ability of riparian zones to function as “sinks” for NO − 3 in watersheds. There has been little analysis of riparian zones in urban watersheds despite concerns about high NO − 3 concentrations in many urban streams. Vegetation and soils in urban ecosystems are often highly disturbed, and few studies have examined microbial processes like denitrification in these ecosystems. In this study, we measured denitrification potential and a suite of related microbial parameters (microbial biomass carbon [C] and N content, potential net N mineralization and nitrification, soil inorganic N pools) in four rural and four urban riparian zones in the Baltimore, MD metropolitan area. Two of the riparian zones were forested and two had herbaceous vegetation in each land use context. There were few differences between urban and rural and herbaceous and forest riparian zones, but variability was much higher in urban than rural sites. There were strong positive relationships between soil moisture and organic matter content and denitrification potential. Given the importance of surface runoff in urban watersheds, the high denitrification potential of the surface soils that we observed suggests that if surface runoff can be channeled through areas with high denitrification potential (e.g., stormwater detention basins with wetland vegetation), these areas could function as important NO − 3 sinks in urban watersheds.