1a. Objectives (from AD-416):
Objective 1: Quantify states, fluxes, and cycling of water, carbon, and hydrologic constituents within the soil-plant-hydrologic-atmospheric systems of selected landscapes, watersheds, and agricultural systems of the Southern Great Plains. Objective 2: Develop tools and techniques for the selection, placement, and evaluation of conservation and agricultural practices to improve watershed integrity and ecosystems services. Objective 3: As part of the LTAR network, and in concert with similar long-term, land-based research infrastructure in the region, use the Little Washita River/Fort Cobb Reservoir Experimental Watersheds LTAR site to improve the observational capabilities and data accessibility of the LTAR network and support research to sustain or enhance agricultural production and environmental quality in agroecosystems characteristic of the Southern Plains region. Research and data collection are planned and implemented based on the LTAR site application and in accordance with the responsibilities outlined in the LTAR Shared Research Strategy, a living document that serves as a roadmap for LTAR implementation. Participation in the LTAR network includes research and data management in support of the ARS GRACEnet and/or Livestock GRACEnet projects.
1b. Approach (from AD-416):
The project builds upon the prior 5-year project and is structured around three inter-related research objectives that: 1) develop, maintain, and expand long-term observational research infrastructure and databases to elucidate water-related agroecosystem processes for agricultural systems, 2) conducts studies that help understand processes and improve algorithms of commonly used hydrologic and water quality models, and 3) develops tools and techniques for the selection, placement, and evaluation of conservation and agricultural practices to improve watershed integrity and ecosystems services. Our long-term objective is to elucidate key hydrologic and agroecosystem processes and to bridge the gap between farm management goals and landscape or watershed goals that are shared across farms and communities, using long-term research sites and research watersheds as the primary outdoor laboratories to address these issues of global relevance. Research approaches include field studies, remote sensing analyses, mathematical and statistical assessment of climate, farm to watershed scale process modeling, and development of integrative optimization tools. This research will assist farmers, land owners, governmental action agencies, and residents to contribute to more resilient mixed land-use watersheds, in part by providing tools that help them evaluate and optimize multiple management objectives for mixed-enterprise agricultural systems.
3. Progress Report:
This project replaces the expirired project 3070-13000-011-00D “Agricultural Land Management to Optimize Productivity and Natural Resource Conservation at Farm and Watershed Scales”, which was completed and terminated during the fiscal year. Site research for the Southern Plains Long-Term Agroecosystem Research (LTAR) was continued on two perennial long-term observational sites. The integrated 10-paddock crop-livestock Common Experiment study site (i.e., the GREEN Farm) was divided into no-till and till treatments following the 2016 wheat harvest. Two paddocks were planted into canola to position the site to have a wheat after canola and other 8 paddocks were cropped to wheat. The planned yield map for 2017 harvest was obtained except for the no-till canola treatment. Progress statement linked to Objective 3. Activities on the GREEN Farm included: 1) completion of flume installation, 2) an electromagnetic induction survey was conducted, 3) measurement of greenhouse gases from static chambers were made, 4) eddy covariance systems were installed on eight of the ten fields to measure fluxes of carbon dioxide, methane, and evapotranspiration, and 5) periodic measurements of biomass, leaf area index, chlorophyll concentration, and hyperspectral canopy reflectance. A new long-term weather station has been established to improve timeliness of data delivery to the Ag Data Commons. Equipment to support Unmanned Aerial Vehicle (UAV) -hyperspectral research was obtained and staff was trained in operation. The scientists and technicians worked with the Ag Commons team on a focused workshop for the Grazinglands Research Laboratory (GRL) data base design which is now in development. The GRL database will facilitate efficient delivery of data to the Ag Data Commons. Collaboration with Oklahoma State University focused on irrigation system efficiency and irrigation management in the Fort Cobb watershed. Most of the planned sensors have been installed. Objective 2. Long-term research sites were leveraged to support National Institute of Food and Agriculture (NIFA)-funded Grazing Coordinated Agricultural Project (CAP) research that focused on resilience of grazing systems to variable climate. Carbon, water, and energy fluxes were measured from perennial and annual grass sites. Nutrient use efficiency of cattle and impact of forage quality on enteric methane emissions were studied during intensive campaigns with CAP collaborations. Studies to calibrate field-scale COsmic-ray Soil Moisture Observing System (COSMOS) soil moisture sensors were established. The animal science team from Bushland, Woodward, Noble Foundation, and El Reno met to discuss analysis and manuscript development from multiple intensive campaigns focused on enteric methane emissions as related to forage/feed quality and environmental conditions. Objective 3. Scientists and postdocs completed development of a modeling software to support to the project funded by the USDA Office of Environmental Marketing (OEM) to parameterize and validate the Agricultural Policy Environmental eXtender (APEX) model to support the nutrient tracking tool (NTT). A manuscript is in preparation. Objective 2.