Research Project: FY 2019 Conservation Effects Assessment Project (CEAP) Agricultural Research Service Benchmark Watershed Assessment Studies (on croplands)

Location: Hydrology and Remote Sensing Laboratory

Project Number: 8042-13610-030-008-I
Project Type: Interagency Reimbursable Agreement

Start Date: Aug 1, 2019
End Date: Sep 30, 2021

Objective:
1. Monitor water quality using real time sensors at two USGS gage stations in the Choptank River watershed. 2. Initiate a water age-dating study using chiral MESA (a metabolite of the herbicide, metolachlor) with other CEAP and LTAR partners. 3. Conduct remote sensing studies of mapping evapotranspiration (ET) for improved watershed model output.

Approach:
ARS will continue monitoring water quality at two USGS gage stations in the Choptank River watershed using in situ optical sensors that measure nitrate and dissolved organic carbon (DOC). The detailed data collected on stream flow and nitrate information will allow us to perform better flow and nitrate calibrations of the SWAT model for these two sub-basins. We will initiate a water age-dating study using chiral MESA (a metabolite of the herbicide, metolachlor) with other CEAP and LTAR partners. The Choptank River has been a test bed for validating the use of an in situ integrative passive sampler methodology for measurement of chiral MESA. We will also continue monthly sampling of 15 subwatersheds to examine DOC and a suite of pesticide and nutrient contaminants. Our remote sensing work will focus on mapping evapotranspiration (ET) with the expectation that improved ET measurements will improve modeling efforts to discern the impacts of increasing irrigation on stream discharge.