Location: Cropping Systems and Water Quality Research
2019 Annual Report
Objectives
Objective 1: Optimize production systems for irrigated cotton, corn, soybean, and rice to improve water use efficiency under variable weather conditions while considering the constraints of timing for field operations, a limited growing season, and increasingly limited water supplies. 1a: Refine irrigation scheduling recommendations for aerobic rice. 1b: Determine crop canopy traits associated with improved drought tolerance in soybean. 1c: Determine the impact of cover crop in a furrow irrigated, minimum tillage, cotton/corn rotation.
Objective 2: Evaluate the suitability of variable-rate center pivot irrigation for crop production on variable soils and in varying weather conditions to determine potential costs and benefits for producers. 2a: Evaluate the potential use of the ARS Irrigation Scheduling and Supervisory Control and Data Acquisition System (ISSCADA) for variable-rate irrigation management of cotton in the sub-humid U.S. Mid-South. 2b: Determine the spatial variability of crop coefficient in a cotton field.
Objective 3: Evaluate the quality of runoff from irrigated cropland to determine current and potential environmental risks and develop guidelines and BMPs to reduce impact of irrigated agriculture on water quality degradation. 3a: Determine nutrient content of runoff from a surface irrigated cotton field in the lower Mississippi River basin.
Approach
Our interdisciplinary team will evaluate systems for irrigated crop production to address key knowledge and technology gaps limiting water use efficiency (WUE) in humid and sub-humid climates where water was generally inexpensive and often considered unlimited. We will conduct field research that incorporates spatial soil, crop, and yield data to develop approaches to optimize production systems to better respond to large spatial and temporal variations in weather that are expected to increase with climate change. We will develop recommendations that take into consideration the constraints of limited timing for field operations, marginal growing seasons for cotton and rice, and water supplies facing increased scrutiny for waste and contamination. We will develop and test methods for improved management of variable-rate center pivot irrigation technology for variable crops, soils, and weather conditions to increase potential benefits for producers. We will also evaluate the quality of runoff from irrigated cropland to determine potential environmental risks and develop guidelines and BMPs to reduce water quality degradation associated with irrigated agriculture.
Progress Report
Project Number 5070-13610-007-00D was initiated during FY17. Under ARS leadership: (1) Continued study of drought tolerance of public and commercial soybean genotypes; relocated study to a center pivot irrigation system equipped with variable rate irrigation (VRI) to allow a wider range of water stress treatments. (2) Collaborated with ARS scientists in Bushland, Texas, Florence, South Carolina, and Stoneville, Mississippi, to test ARS-developed system for VRI management. Presented findings from the study at The 12th European Conference on Precision Agriculture. Revised treatments, planted study, and installed sensors for crop canopy temperature and soil moisture measurement for 2019 growing season. (3) Continued observations to determine the spatial variability of crop coefficient in a cotton field to improve VRI management. (4) Because the studies in this project rely on yield monitor data for harvest results, studies on yield monitor performance have been included. An article on the influence of variety on cotton yield monitor performance combining multiple years’ data was published.
In conjunction with the Research Unit’s NP216 project: (1) Investigated soil sensing systems for better characterization of the highly variable soils of the Upper Mississippi Delta. Our approach is to combine mobile sensors that provide good coverage across fields with vertical-probing sensors that provide information about how soils vary with depth. A recently completed analysis showed that this approach was able to create maps of how soil texture varies with depth across fields, which will be useful for VRI management. Prepared and presented article relating soil properties and irrigation effects at 5th Global Proximal Soil Sensing Workshop. (2) Collected in-season data on changes in soil properties in the field.
Through a Non Assistance Cooperative Agreement with the University of Missouri (MU) (5070-13610-007-01S): (1) Maintained three real-time weather stations at research facilities in southeast Missouri with web access to the information as part of the Missouri Mesonet. (2) Continued tests using VRI to evaluate irrigation treatments for center pivot irrigated rice, corn, and cotton based on evapotranspiration calculated from on-site weather station data; observed response to later irrigations for center pivot rice than for flooded rice. (3) Continued long-term study of effect of cover crops and reduced tillage on irrigated corn and cotton; observed increases in corn yield associated with both irrigation and cover crop. (4) Collected data using an unmanned aerial vehicle (UAV); published article, prepared additional articles, and presented findings at 2019 American Society of Agricultural and Biological Engineers Annual International Meeting. (5) Cotton yields trended greater with increases in irrigation frequency. However, waiting to trigger irrigation saved water. (6) Completed land use and land cover characterization of the Big Oak Tree State Park and the surrounding areas. Compiled areal and satellite-acquired images for the period 1995-2018 and assessed the changes in vegetation. Completed land cover classification, which will be used in groundwater-wetland dynamics assessment.
Accomplishments
1. Demonstrated influence of irrigation pattern on effectiveness of furrow irrigation. Sufficient groundwater is available for effective surface irrigation in many areas of the Mid-South growing region of the U.S. However, producers commonly employ patterns such as every-other-furrow irrigation to allow them to irrigate fields in one set and thereby avoid the time and labor required to revisit the field to change sets. Because producers are concerned that yield could be reduced by the practice, ARS researchers in Portageville, Missouri, and university collaborators conducted a study during the 2014 through 2016 growing seasons to investigate the impact of different furrow irrigation patterns on cotton yield. Although questions about the impact of irrigating less than every furrow during an especially dry year led to the study, no extremely dry growing season occurred during the study. While yield loss due to waterlogging is a constant concern in the region and often causes producers to delay irrigation, no such losses were indicated. Documenting when drought stress and waterlogging are most likely to occur will allow farmers throughout the world to irrigate their crops more economically and efficiently, ensuring a stable supply of food, feed, and fiber.
2. Documented variety effects on cotton yield monitor calibration. Accurate yield monitor performance is essential to improving precision agriculture. Knowledge of which factors affect the agreement between measured cotton yields and those estimated with yield monitors must be improved to ensure that appropriate inferences are drawn from the harvest data. ARS researchers in Portageville, Missouri, and university collaborators analyzed data collected with two yield monitor systems, comparing monitor-estimated weights to observed weights in replicated cotton variety trials. For six site-years of data and three combinations of two site-years, correlations were sometimes observed between calibration errors and other factors, but no correlations were consistent across multiple studies. Additional data must be collected and analyzed to determine which variety-related properties affect cotton yield monitor errors and to allow the development of calibration adjustments based on those factors. This will allow researchers and farmers throughout the world to advance precision agriculture methods for cotton to ensure a stable supply of food, feed, and fiber.
Review Publications
Drew, P.L., Sudduth, K.A., Sadler, E.J., Thompson, A.T. 2019. Development of a multi-band sensor for crop temperature measurement. Computers and Electronics in Agriculture. 162:269-280. https://doi.org/10.1016/j.compag.2019.04.007.
Vories, E.D., Jones, A.S. 2018. Influence of irrigation pattern on effectiveness of furrow irrigation of cotton. Journal of Cotton Science. 22(3):153-161.
Pei, X., Sudduth, K.A., Veum, K.S., Li, M. 2019. Improving in-situ estimation of soil profile properties using a multi-sensor probe. Sensors. 19(5):1011. https://doi.org/10.3390/s19051011.
Veum, K.S., Parker, P., Sudduth, K.A., Holan, S.H. 2018. Predicting profile soil properties with reflectance spectra via Bayesian covariate-assisted external parameter orthogonalization. Sensors. 18(11):3869. https://doi.org/10.3390/s18113869.
Feng, A., Zhang, M., Sudduth, K.A., Vories, E.D., Zhou, J. 2019. Cotton yield estimation from UAV-based plant height. Transactions of the ASABE. 62(2):393-403.
Vories, E.D., Jones, A., Meeks, C., Stevens, G. 2019. Variety effects on cotton yield monitor calibration. Applied Engineering in Agriculture. 35(3):345-354.
