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Updated: May 17, 2026
12:50
Continuous Instream Monitoring of Nutrients and Sediment in Agricultural Watersheds
Published on: September 26, 2017
Soil nitrogen dynamics in a river floodplain mosaic.
J Shrestha1, P A Niklaus, E Frossard
1Swiss Federal Institute for Forest, Snow, and Landscape Research, Birmensdorf, Switzerland.
Journal of Environmental Quality
|November 7, 2012
Summary
Restored floodplains enhance nitrogen removal through varied habitats. Heterogeneity in restored areas promotes nitrogen cycling and retention, unlike channelized sections.
Area of Science:
- Ecology
- Environmental Science
- Soil Science
Background:
- River floodplains are dynamic ecosystems crucial for nitrogen retention and removal from surface waters.
- Understanding nitrogen dynamics in different floodplain habitats is essential for ecosystem management and restoration.
Purpose of the Study:
- To compare soil nitrogen dynamics across diverse habitat patches in restored and channelized sections of the Thur River floodplain.
- To link nitrogen pools, transformations, and gaseous emissions to soil properties and hydrological processes.
Main Methods:
- Investigated soil nitrogen pools (ammonium, nitrate, microbial nitrogen) and transformations (mineralization, nitrification, denitrification).
- Measured gaseous nitrogen (NO) emissions.
- Related nitrogen dynamics to soil properties (water content, carbon availability) and hydrological factors (sedimentation, inundation).
Main Results:
- Soil water content and carbon availability, influenced by sedimentation and inundation, were key drivers of nitrogen dynamics.
- High nitrogen turnover rates were observed in gravel bars and alluvial forests, indicating efficient nitrogen removal.
- Channelized embankment soils showed lower inorganic nitrogen pools and transformation rates, especially for nitrate production.
Conclusions:
- Environmental heterogeneity in restored floodplains enhances nitrogen removal via sedimentation and denitrification.
- Restored floodplains effectively promote nitrogen cycling and retention compared to channelized sections.
- Potential concerns include localized high nitrogen oxide (NO) efflux and nitrate leaching from nitrification hotspots.
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