Location: Soil and Water Management Research2017 Annual Report
The long-term goal of this project is to prolong the economic activity derived from the Ogallala Aquifer by providing knowledge, tools, and technologies for water conservation and scientifically sound water use policies. Specifically, during the next five years, we will focus on: Objective 1. Improve the management of the Ogallala Aquifer by developing tools and knowledge of hydrological properties and water budget components. Subobjective 1.A: Improve the characterization of the Ogallala Aquifer including locations and rates of recharge. Subobjective 1.B: Integrate remotely-sensed data into water resource monitoring and decision support tools. Objective 2. Improve the efficiency by which agriculture converts water into food, feed, fuel and fiber. Subobjective 2.A: Improve irrigation scheduling technologies, strategies, and practices. Subobjective 2.B: Develop improved design, performance and management of irrigation control and application systems. Subobjective 2.C: Determine best management practices (BMP) for water-limited production of crop, fuel and forage in a semi-arid region. Subobjective 2.D: Improve knowledge of crop water demand and productivity at field, region and aquifer scales. Objective 3. Facilitate the adoption of water conservation practices by providing estimates of the socio-economic impacts of various water management activities and policies. Objective 4. Provide data, knowledge, and decision support systems to farmers, ranchers, water-policy makers, and the general public.
This cooperative project between the ARS (Bushland and Lubbock, Texas), Kansas State University, Texas A&M University, Texas Tech University, and West Texas A&M University, elucidates innovative management technologies appropriate for the Ogallala Aquifer region of the U.S. to enhance and sustain rural economies. The results are applicable to other areas in which there is increasing demands on the water supply. The in-research program addresses issues related to water management practices in cropping and integrated crop-livestock systems, and irrigation management and automation for increased water use efficiency (WUE). Knowledge of the processes affecting soil water content during a growing season will facilitate refinement of models to simulate water balance and assist in assessing the merits of alternative practices. Longer-term studies will be used to quantify effects of reduced tillage on crop yield, WUE, and soil physical characteristics for wheat-sorghum-fallow crop rotations and alternative cropping sequences. Several experiments focusing on different hydrological aspects and time scales will investigate management effects on soil water and availability to crops utilizing watershed, remote sensing, and meteorological networks. Research approaches related to irrigation management include determinations of crop water use by weighing lysimeters, neutron scattering methods, etc. Experiments include variations in irrigation methods, irrigation amount, tillage, and/or crop and crop rotation. Automatic irrigation systems based on sensing of crop water status are being engineered and tested. Remote sensing approaches to water use prediction are expected to improve their utility in decision making by farm managers, irrigation projects or water districts, and policy makers. University partners have critical roles in supporting the above activities as well as providing additional expertise in technology transfer, hydrology and economic assessments of existing and future water conservation technologies and policies. Support from cooperating university is evaluated annually. Work plans are developed for each project describing research to be conducted during a 2-year period. Yearly workshops are held with stakeholders and cooperating scientists; these workshops are used to review progress, re-define or clarify research priorities, and inform stakeholders, project leaders and administrators. Annual and final reports are used to document progress of the research.
This serves as the final report for this research project. The research conducted under this research project was a continuation of a long running program in water management research and conservation technologies. An evolution of this research program will continue under the new research project 3090-13000-015-00D. Most of the proposed research in Objectives 1 through 4 were completed during the life of this projects. Understanding of the partitioning of evapotranspiration (ET) into evaporation from the soil and transpiration by plant was advanced, in particular in refinement of the two source energy balance model (Objective 1). The research team organized two multi-partner field campaigns centered on the large weighing lysimeters at Bushland to determine better methods of determining crop water use and other components of the energy and water balances in an advective environment. The team has published more than 20 peer-reviewed journal articles advancing the understanding of eddy covariance, modeling, remote sensing, lysimeter and soil water balance methods of ET determination since 2011. Advances have been made in developing soil and plant sensors to aid with scheduling deficit irrigation strategies (Objective 2). Cooperatively with a commercial partner, the team developed a system for sensing soil water content and bulk electrical conductivity in 0.20-m vertical segments to arbitrary depth. ARS researchers at Bushland, Texas led a multi-national effort to compare and understand soil water sensing methods and develop guidelines for their selection and use. The irrigation research team installed variable rate irrigation (VRI) systems in cooperation with a commercial partner on two center pivot irrigation systems and tested the spatial application control and accuracy under windy conditions typical of the wind-energy-rich Southern High Plains. The Bushland irrigation team developed an Irrigation Scheduling Supervisory Control and Data Acquisition system for control of pressurized irrigation systems, patented it, and developed the underlying wireless sensor technologies for plant stress and soil water status. Assessment of the economic impacts of several proposed water policy have been completed (Objectives 3). Economic impact of several segments of the Southern High Plains agri-businesses (beef feedlots, dairies, wheat, etc.) have been summarized. Findings from economic assessments were instrumental in the passage of four water policies changes in the Kansas. Economic and hydrologic data have been conducted to determine the successes of local enhanced management areas in Kansas. Technology transfer events have been presented to thousands of stakeholders regarding knowledge and technologies related to water conservation and irrigation efficiency (Objective 4). Project scientists have been interviewed for numerous public press items that stress the importance of the Ogallala Aquifer to American agriculture.
Colaizzi, P.D., Evett, S.R., Brauer, D.K., Howell, T.A., Tolk, J.A., Copeland, K.S. 2017. Allometric method to estimate leaf area index for row crops. Agronomy Journal. 109(3):1-12.
Colaizzi, P.D., OShaughnessy, S.A., Evett, S.R., Mounce, R.B. 2017. Crop evapotranspiration calculation using infrared thermometers aboard center pivots Agricultural Water Management. 187:173-189.