Agricultural Demonstration Initiative
Collaborators evaluate irrigation water use efficiency in citrus
By Danielle Supercinski
With water scarcity being a prominent issue for growers, Rio Grande Basin Initiative researchers are collaborating with a Lower Rio Grande Valley (LRGV) project aimed at demonstrating cost-effective and efficient irrigation technologies to growers.
RGBI researcher Dr. Shad Nelson, soil scientist at Texas A&M University–Kingsville, is collaborating with the Agricultural Water Conservation Demonstration Initiative (ADI) project to evaluate irrigation use efficiency. Sponsored by the Texas Water Development Board (TWDB), ADI demonstrates cost-effective technologies integrating state-of-the-art irrigation water distribution network control and management, and on-farm irrigation technology and management systems.
In 2002, Nelson joined the RGBI on-farm irrigation management team to evaluate drip and microjet spray compared with flood irrigation practices in citrus production. These preliminary RGBI investigations regarding water conservation in citrus helped to leverage funds from the TWDB to evaluate on-farm water conservation field demonstration projects in citrus, vegetable and crop production on various growers’ farms throughout the LRGV over a 10 year time span (2005-2014).
Through the ADI, Nelson focuses on potential low-use irrigation strategies in citrus and vegetable production within the Valley. Other research focuses on comparing water use efficiency from conventional flood and furrow irrigation practices to crop production using drip, sprinkler or microjet-spray irrigation.
“It is anticipated that as we gather more information from designated demonstration sites, that field days will be planned for other growers to attend that are interested in these projects and potential water conserving practices,” Nelson said.
Nelson works with Dr. Juan Enciso, agricultural engineer at the Texas A&M Agricultural Research & Extension Center in Weslaco, to establish agreements with growers within the LRGV who are willing to participate in a long-term evaluation of crop production and water use using different irrigation systems. Currently, under their direction, 14 growers are associated with the ADI project with 27 working field sites and crop locations. Citrus crops include grapefruit, oranges and tangerines, and vegetable crops include onions, celery and corn.
“These demonstration sites focus on various irrigation methods such as drip, microjet-spray, flood, furrow and polypipe furrow irrigation systems,” Nelson said.
An integral part of water conservation is monitoring water consumption. Soil moisture monitoring can be an effective mechanism improving crop sustainability by scheduling irrigation based on soil moisture levels. To effectively study the soil moisture regime in different soil profiles and under different crops, soil moisture sensing equipment has been installed along with automated data loggers and rain tipping buckets to measure precipitation on-site, he said.
“Data is periodically downloaded for further evaluation of the plant available water content and the moisture movement patterns in the soil profile,” Nelson said. “Crop water requirements throughout the production season will help us better identify efficient strategies for sustainable crop production and improved crop water use efficiency.”
Others working with the ADI project under Nelson are Heriberto “Eddie” Esquivel, ADI project coordinator for TAMU–Kingsville, and graduate students who are currently training in geographical information systems (GIS) programming to be able to dedicate these skills to various sites across the LRGV. Nelson said goals include correlating data with different irrigation practices to establish a “rule of thumb” aspect in relation to available soil moisture content and when irrigation must be added.
“We anticipate that information gathered from these on-farm demonstration sites will provide meaningful information to all growers in the LRGV and provide an accurate picture of how cost effective alternative irrigation practices are and will be in the near future,” Nelson said. “This is an exciting and rare opportunity for growers to participate in meaningful projects that will impact irrigated agriculture in the Valley.”
ADI has contracted the services of Texas A&M University–Kingsville, Texas Cooperative Extension Service, Delta Lake Irrigation District and Axiom-Blair Engineering. These agencies assist ADI with technical support, economic evaluation and execution of the demonstration projects. For more information and newsletters on the ADI project, visit http://www.hidcc1.org/node/6.
