Location: Soil Management and Sugarbeet Research
Project Number: 3012-12210-001-012-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Feb 15, 2022
End Date: Sep 30, 2025
Objective:
The purpose of this agreement is to coordinate legacy phosphorus (P) project activities in the Lake Champlain watershed with a larger, national-scale project occurring in multiple states. The goal of the larger scale project is to discern the potential contribution of legacy P sources to watershed P discharges/dynamics across USDA-funded research watersheds. The following objectives for Phases 1 and 2 of the project are specific to the Lake Champlain Watershed and are the basis of this agreement:
Phase 1, goal 1. Characterize legacy P sources in research watersheds, with locally derived, and common, methods.
Phase 1, goal 2. Assess long-term (>5 yr) Edge-of-Field and small watershed data to assess contributions of new/recent/incidental vs. old/legacy/chronic sources of legacy P.
Phase 1, goal 3. Advance management recommendations to comprehensively address legacy P and non-legacy P sources, including to be used as scenarios by watershed modelers.
Phase 2, goal 1. Improve the representation of legacy phosphorus processes in simulation models that are important to watersheds targeted under Phase 1
Phase 2, goal 2. Assess the baseline contribution of legacy phosphorus to watershed outcomes within the Lake Champlain watershed using SWAT/APEX
Phase 2, goal 3. Quantify watershed outcomes of watershed-specific recommendations developed as part of Phase 1.
Approach:
For each objective, the following research approach will be implemented:
Phase 1, goal 1. Characterize legacy P sources in research watersheds, with locally derived, and common, methods. This will involve sampling soils within multiple locations within the Lake Champlain watershed where water quality monitoring activities are underway. Nested sites will be a priority for soil sampling. Specifically, a CEAP Innovative Stacked Practices study site will be targeted, which exists within a subwatershed of the treatment watershed of the Lake Champlain watershed CEAP Paired Watersheds project (i.e., the East Branch of the Dead Creek). Characterization will also occur at other locations within the Lake Champlain watershed, including the Headwaters Little Otter Creek watershed, main stem of the Dead Creek, and the Jewett Brook watershed. All of the selected locations are characterized by soils that are representative of the dominant farmed soils of the Lake Champlain watershed. The spatial and temporal sampling strategy will be determined through consultation with project partners to enjoy commonalities and feasibility. Soil samples will be split and analysis of one split will occur at a common lab along with project cooperators’ soils from the other study areas. The other split will be analyzed at the UVM Agricultural and Environmental Testing Laboratory per methods TBD. UVM will work with the Project Director Kleinman and other ARS cooperators to use existing models (e.g., SWAT, APEX, AnAgNPS, SPARROW) to inform decisions on metrics so that they may be implemented later. The emphasis will be on P characterization in soils, but sediments will be investigated where and when feasible.
Phase 1, goal 2. Assess long-term (>5 yr) Edge-of-Field and small watershed data to assess contributions of new/recent/incidental vs. old/legacy/chronic sources of legacy P. Data from at least four edge-of-field monitoring stations will be assembled for this objective and organized to facilitate ease-of-use by ARS scientists performing the modeling activities. Datasets will include hay, hay with aeration prior to manure application, corn silage with conventional tillage surface manure application, and corn silage with no tillage, manure injection, and a cover crop. Soils will include alluvial flood-plain soils and clay-textured soils (dominating the Lake Champlain watershed). Data will be analyzed through cooperation with ARS scientists.
Phase 1, goal 3. Advance management recommendations to comprehensively address legacy P and non-legacy P sources, including to be used as scenarios by watershed modelers. Local knowledge will be utilized to identify key management practices that have the greatest potential for addressing P loss in the Lake Champlain watershed. Those practices/management changes will also be vetted with Extension personnel and agricultural service providers regarding their adaptability for implementation within the region’s farming systems.
Phase 2, goal 1. Improve the representation of legacy phosphorus processes in simulation models that are important to watersheds targeted under Phase 1. (a) contribute to local simulation mod.
