Journal article
Water and nutrient discharge to a high‐value terrace–floodplain fen: resilience and risk
Ecohydrology, Vol.9(7), pp.1196-1207
10/2016
DOI: 10.1002/eco.1718
Abstract
While fens provide a host of ecosystem services, those located at the base of river terraces are under threat from upgradient agricultural activities. We investigated a fen located along the boundary of the highly agricultural terrace and modern floodplain of the Cedar River in southeast Iowa using a transect of groundwater and surface water monitoring points. During the three‐year monitoring period, the water table level in the terrace fluctuated 55 cm in the terrace, but hydraulic head in the fen varied only 18 cm during a severe drought that occurred in the region. Fen water table levels were significantly related to those measured in the adjacent terrace but groundwater flow to the fen from regional aquifer sources appeared to provide resilience against large fluctuations in fen water table levels. Terrace groundwater discharging into the fen from a spring at the terrace base had NO3–N concentrations as high as 16 mg/l, averaging approximately 8 mg/l during the study. Concentrations were significantly lower in fen groundwater, likely due in part to denitrification occurring in the organic‐rich fen deposits. PO4–P concentrations were less variable (ranging from 0.04 to 0.1 mg/l) but were significantly higher (1.2 mg/l) in the low‐redox fen groundwater. Conservation of these unique and high‐value terrace–fen ecosystems should be made a priority through additional hydrologic investigation and local land management. Copyright © 2015 John Wiley & Sons, Ltd.
Details
- Title: Subtitle
- Water and nutrient discharge to a high‐value terrace–floodplain fen: resilience and risk
- Creators
- Keith E. Schilling - United States Geological SurveyPeter J. Jacobson - Grinnell College
- Resource Type
- Journal article
- Publication Details
- Ecohydrology, Vol.9(7), pp.1196-1207
- DOI
- 10.1002/eco.1718
- ISSN
- 1936-0584
- eISSN
- 1936-0592
- Number of pages
- 12
- Grant note
- Grinnell College Iowa Chapter of The Nature Conservancy
- Language
- English
- Date published
- 10/2016
- Academic Unit
- Earth and Environmental Sciences; IIHR--Hydroscience and Engineering
- Record Identifier
- 9984383316002771
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