Journal article
Effectiveness of a newly reconstructed floodplain oxbow to reduce NO3-N loads from a spring flood
Journal of environmental management, Vol.215, pp.385-393
06/01/2018
DOI: 10.1016/j.jenvman.2018.03.070
PMID: 29604545
Abstract
Enhancing NO3-N processing in floodplains offers opportunities to achieve water quality improvements in agricultural watersheds but few studies have quantified the effectiveness of newly reconstructed oxbows to reduce loads delivered from floods, In this study, we evaluated NO3-N retention during a spring storm water runoff event in a newly reconstructed oxbow (<1 year old) located along Morgan Creek in eastern Iowa. A 30-h flood connected the oxbow to the creek for approximately nine hours and delivered 14.7 kg of NO3-N into the oxbow. Using a NO3-N sensor, oxbow NO3-N concentrations were observed to increase from 0.7 to 5.3 mg/I after the flood event, but decreased to background conditions over the next 21 days. We estimated NO3-N retention to be 0.30 gN m(-2) d(-1) and the NO3-N retention efficiency to be 74.2% for the single flood event. The NO3-N mass reduction in the oxbow intersected with predicted mass reduction from a first-order denitrification decay model after 21 days which suggests that denitrification was largely responsible for the observed NO3-N decrease. However, the effectiveness of the oxbow for reducing watershed-scale N loads appears to be limited, since the oxbow is located in a low-nutrient floodplain and would only retain NO3-N loads when delivered to the oxbow via flooding. Study results suggest that oxbows provides valuable ecosystem services during non-flooding periods and are activated for NO3-N load reduction during floods. (C) 2018 Elsevier Ltd. All rights reserved.
Details
- Title: Subtitle
- Effectiveness of a newly reconstructed floodplain oxbow to reduce NO3-N loads from a spring flood
- Creators
- Keith E. Schilling - Iowa Geological Survey, University of Iowa, Iowa City, IA, USA. Electronic address: keith-schilling@uiowa.edu.Bryce J. Haines - University of IowaChristopher S. Jones - University of IowaMartin St Clair - United States Army Corps of Engineers
- Resource Type
- Journal article
- Publication Details
- Journal of environmental management, Vol.215, pp.385-393
- Publisher
- Elsevier
- DOI
- 10.1016/j.jenvman.2018.03.070
- PMID
- 29604545
- ISSN
- 0301-4797
- eISSN
- 1095-8630
- Number of pages
- 9
- Grant note
- Iowa Nutrient Research Center
- Language
- English
- Date published
- 06/01/2018
- Academic Unit
- Earth and Environmental Sciences; IIHR--Hydroscience and Engineering
- Record Identifier
- 9984383303302771
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