Location: Water Quality and Ecology ResearchTitle: Characterization and placement of wetlands for integrated watershed conservation practice planning Author
|Bingner, Ronald - Ron|
Submitted to: Transactions of the ASABE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/4/2016
Publication Date: 11/10/2016
Publication URL: http://handle.nal.usda.gov/10113/63297
Citation: Momm, H.G., Bingner, R.L., Yuan, Y., Kostel, J., Monchak, J., Locke, M.A., Giley, A. 2016. Characterization and placement of wetlands for integrated watershed conservation practice planning. Transactions of the ASABE. 59(5): 1345-1357. 2016.. Interpretive Summary: Technology has been developed to identify and characterize wetlands within watershed systems. The placement of wetlands within watershed systems can be part of a system-wide plan to reduce pollutant loads moving downstream by trapping and transforming nutrients. Management tools are needed to evaluate the effectiveness of wetlands used in conjunction with a watershed system approach of implementing conservation practices. Without these tools, the placement of wetlands can be subjective without quantitatively assessing their impact on reducing pollutant loads moving further downstream. Wetland identification and characterization using newly developed Geographic Information System (GIS) wetland management tools linked with watershed management models provides improved planning tools to action agencies. The characteristics of each wetland can be automatically determined to describe the main parameters used in models, such as the wetland area, wetland barrier height, and the location and extent of each wetland within a watershed. Examples will be discussed on the use of the wetland feature based on a 125,000 ha watershed located in North-Central Illinois. Wetlands in series or individually can be created and evaluated using the model for their effect on downstream pollutant loadings. This information can then be part of a decision-making approach to conservation management planning.
Technical Abstract: Constructed wetlands have been recognized as an efficient and cost-effective conservation practice to protect water quality through reducing the transport of sediments and nutrients from upstream croplands to downstream water bodies. The challenge resides in targeting the strategic location of wetlands within agricultural watersheds to maximize the reduction in nutrient loads while minimizing their impact on crop production. Furthermore, agricultural watersheds involve complex interrelated processes requiring a systems approach to evaluate the inherent relationships between wetlands and multiple sediment/nutrient sources (sheet, rill, ephemeral gully, channels) and other conservation practices (filter strips). This study describes new capabilities of the U.S. Department of Agriculture’s Annualized Agricultural Non-Point Source pollutant loading model, AnnAGNPS. A developed AnnAGNPS GIS-based wetland component, AgWet, is introduced to identify potential sites and characterize individual constructed or natural wetlands at a watershed scale. AgWet provides a simplified, semi-automated, and spatially distributed approach to quantitatively evaluate wetlands as potential conservation management alternatives. AgWet is integrated with other AnnAGNPS components providing seamless capabilities of estimating the potential sediment/nutrient reduction of individual wetlands. This technology provides conservationists the capability for improved management of watershed systems and support for nutrient credit trading programs.