| Title: | Keeping agricultural soil out of rivers: evidence of sediment and nutrient accumulation within field wetlands in the UK |
| Author(s): | Ockenden MC; Deasy C; Quinton JN; Surridge B; Stoate C; |
| Address: | "Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK. Electronic address: m.ockenden@lancaster.ac.uk. Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK. Game & Wildlife Conservation Trust, Loddington House, Main Street, Loddington, Leicestershire LE7 9XE, UK" |
| DOI: | 10.1016/j.jenvman.2014.01.015 |
| ISSN/ISBN: | 1095-8630 (Electronic) 0301-4797 (Linking) |
| Abstract: | "Intensification of agriculture has resulted in increased soil degradation and erosion, with associated pollution of surface waters. Small field wetlands, constructed along runoff pathways, offer one option for slowing down and storing runoff in order to allow more time for sedimentation and for nutrients to be taken up by plants or micro-organisms. This paper describes research to provide quantitative evidence for the effectiveness of small field wetlands in the UK landscape. Ten wetlands were built on four farms in Cumbria and Leicestershire, UK. Annual surveys of sediment and nutrient accumulation in 2010, 2011 and 2012 indicated that most sediment was trapped at a sandy site (70 tonnes over 3 years), compared to a silty site (40 tonnes over 3 years) and a clay site (2 tonnes over 3 years). The timing of rainfall was more important than total annual rainfall for sediment accumulation, with most sediment transported in a few intense rainfall events, especially when these coincided with bare soil or poor crop cover. Nutrient concentration within sediments was inversely related to median particle size, but the total mass of nutrients trapped was dependent on the total mass of sediment trapped. Ratios of nutrient elements in the wetland sediments were consistent between sites, despite different catchment characteristics across the individual wetlands. The nutrient value of sediment collected from the wetlands was similar to that of soil in the surrounding fields; dredged sediment was considered to have value as soil replacement but not as fertiliser. Overall, small field wetlands can make a valuable contribution to keeping soil out of rivers" |
| Keywords: | Agriculture/methods Carbon/analysis Environmental Monitoring/*methods Food Geologic Sediments/*chemistry Nitrogen/analysis Phosphorus/analysis Rivers/*chemistry Soil/*chemistry United Kingdom Wetlands Catchment management Constructed wetlands Diffuse poll; |
| Notes: | "MedlineOckenden, Mary C Deasy, Clare Quinton, John N Surridge, Ben Stoate, Chris eng Research Support, Non-U.S. Gov't England 2014/02/11 J Environ Manage. 2014 Mar 15; 135:54-62. doi: 10.1016/j.jenvman.2014.01.015. Epub 2014 Feb 6" |
