Development and Delivery of Educational Tools for Irrigation Water ...

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As a result, water management tools and protocols for conservation of this resource has ... Mississippi Irrigation Scheduling Tool (MIST), it became evident that ...
An ASABE Meeting Presentation Paper Number: 131619807

Development and Delivery of Educational Tools for Irrigation Water Management and On-Farm Implementation of the Mississippi Irrigation Scheduling Tool (MIST) A.M. Schmidt1, G.F. Sassenrath2, J. Crumpton3, J.Q. Corbitt4, B. Rice3, H. van Riessen5, R. Thornton3, R. Prabhu3, J. Pote3, C. Wax3, M.L. Tagert3 1

University of Nebraska, Lincoln, NE, United States Kansas State University, Parsons, KS, United States 3 Mississippi State University, Starkville, MS, United States 4 USDA Agricultural Research Service, United States 5 Delta State University, Cleveland, MS, United States 2

Written for presentation at the 2013 ASABE Annual International Meeting Sponsored by ASABE Kansas City, Missouri July 21 – 24, 2013 (The ASABE disclaimer is in a table which will print at the bottom of this page.) Abstract. Agricultural crop producers in Mississippi have always enjoyed plentiful water resources for irrigating crops. As a result, water management tools and protocols for conservation of this resource has been limited. The decline in the level of the Mississippi River Alluvial Aquifer, which supplies groundwater in the western region of Mississippi known as the Delta, has generated concern about overuse of groundwater and caused water conservation to become a necessity in crop production systems. Through development of the Mississippi Irrigation Scheduling Tool (MIST), it became evident that educating the region’s agricultural crop producers on managing water based on the needs of the crops was paramount to successful implementation and use of an irrigation scheduling tool. Basic knowledge of soil-water interactions, plant water use, and crop water utilization became the basis for development of a Mississippi State Extension Service-hosted website that would also become the launching point for the MIST. Agricultural crop producers serving as cooperators to help test and validate the MIST prediction model during the 2011 and 2012 growing seasons were utilized to determine preferred terminology for discussing crop water use with end-users. Additional educational and decision support materials were developed to instruct cooperating producers on implementation of the MIST. This paper includes discussion of the educational needs input from cooperating producers and development of educational outputs. Keywords. irrigation, water management, implementation, delivery, education

Introduction Farmers are being increasingly challenged to enhance production with fewer inputs and less environmental impact. Managing and applying supplemental water to fields based on needs of a crop is one way to improve crop performance. Depending on the growing environment, soils and cultivar, average yield for irrigated corn can be 2.3 times that of rain-fed corn. Likewise, research by the USDA-ARS and Mississippi State University reveals a nearly 50% loss of yield for soybeans grown under rain-fed production, depending on planting date. Knowing when to irrigate and how much water to apply are collectively known as “irrigation scheduling.” Before producers can begin to consider adopting irrigation scheduling as a water management method, it is necessary for them to understand the relationship between water management and crop production. It is equally important for educators delivering water management education to understand the capabilities and limitations of crop producers so that appropriate terminology and technology can be used to optimize the learning experience. From previous research, we know that acceptance of new technology is often predicated on the accessibility of scientists and extension personnel to farmers (Sassenrath et al., 2010). A significant component of the development and delivery of the MIST program involved creating educational tools to enhance producer understanding and adoption of the technologies involved in the MIST. The primary goal in delivering educational materials related to the MIST program was to equip crop producers in the Southeast with tools to improve crop production and management including:  Knowledge of crop and soil water relations,  Information on irrigation methods and technology  Irrigation scheduling tools for better water management, and  Economic benefits of water conservation technologies.

Methods Cooperating producers on the MIST project were selected to incorporate a broad range of geographic and production system characteristics. It was recognized that crop producers may utilize knowledge from a wide variety of media sources including university coursework, Extension publications, internet sites, text books, etc. By selecting producers with varying economic, social, and geographic backgrounds, educational components could be developed to address the variety of learning styles and information sources used by the target endusers. Discussions with cooperating producers revealed a need for educational material about: 1) how soil, water and plants interact; 2) soil, water, and plant terminology used in irrigation scheduling; 3) the many types of soil water; 4) the relationship between soil and water; 5) irrigation scheduling; 6) methods for measuring plant water use; 7) methods for measuring soil water; 8) methods for estimating ET from weather parameters; 9) types of irrigation systems; and 10) checking irrigation system performance. To deliver water resource management educational materials, a website was developed with information on water management, crop and soil water relations, and the economic benefits of water conservation practices. The website also supports the online irrigation scheduling tool, the Mississippi Irrigation Scheduling Tool (MIST).

The authors are solely responsible for the content of this meeting presentation. The presentation does not necessarily reflect the official position of the American Society of Agricultural and Biological Engineers (ASABE), and its printing and distribution does not constitute an endorsement of views which may be expressed. Meeting presentations are not subject to the formal peer review process by ASABE editorial committees; therefore, they are not to be presented as refereed publications. Citation of this work should state that it is from an ASABE meeting paper. EXAMPLE: Author’s Last Name, Initials. 2013. Title of Presentation. ASABE Paper No. ---. St. Joseph, Mich.: ASABE. For information about securing permission to reprint or reproduce a meeting presentation, please contact ASABE at [email protected] or 269-932-7004 (2950 Niles Road, St. Joseph, MI 49085-9659 USA). 2013 ASABE Annual International Meeting Paper

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Results and Discussion Improving access and use of latest knowledge and information is enhanced through web-based tools accessible through hand-held devices such as smart phones, tablets, and laptop computers. The education tools and irrigation scheduling tool were designed for maximal ease of access. Implementing the water management tools through a single web location gives the end user production tools, educational information, and explanations all in one site. The web-based tool is coded in Java, and the user interface implemented in HTML (Rice et al., 2013). To keep load-time to a minimum, education pages were written briefly, with embedded graphs or illustrations as needed (Figure 1).

Figure 1. Sensors measuring soil water in a soybean crop

Terminology used on the explanation pages are linked to definitions in an on-line glossary of terms (Figure 2). Particular attention was given to defining the scientific process of data collection, irrigation scheduling, and decision making:

[Soil, Water and Plant Terms Used in Irrigation Scheduling] Allowable Depletion Volume: (sometimes call Maximum Allowable Depletion, or, MAD) the amount of soil water that can be removed from the soil by the plant before an irrigation is needed. It is based on the minimum amount of water needed in the soil that is available to the plant to maintain crop yield and quality Crop Water Use: the amount of water taken up by the plant for use in growth, metabolism and transpiration; usually measured in inches per day Depletion Volume: the amount of “plant available water” removed from the soil since the last irrigation or precipitation event Evapotranspiration (ET): the combination of water evaporated from the soil surface and transpired by plants growing in the soil Field Capacity: the condition at which soil has an amount of water remaining 2-3 days after a soaking rain that completely saturates the soil Irrigation Scheduling: the process of managing water resources to balance the needs of the plants, conservation of water resources, and economic expense of application; used to develop the timing and amount of irrigation required by crops 2013 ASABE Annual International Meeting Paper

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Plant Available Water (PAW): the volume of water stored in the soil that plants can access and use; usually expressed as a depth of water per unit depth of soil; depends on soil texture Potential Evapotranspiration (ETp): the amount of water that can be lost through ET based on atmospheric conditions Saturation: condition where soil pores are completely filled with water (all air has been removed); soils that remain at saturation result in poor plant growth due to lack of oxygen needed for root growth Soil hydrology: characteristics of soil water; dependent on a variety of factors, most importantly soil texture Soil pores: areas between the soil particles that can be filled with water or air; size of the soil pores is dependent on a number of things, but most importantly the amount of sand, silt or clay in the soil Soil texture: the “feel” of the soil, or texture; determined by the amount of sand, silt and clay in the soil. Sandy soils are course textured soils that feel gritty. The soils are easily worked, but water drains quickly from sandy soils such as Clack or Crevasse. Silty (loamy) soils are medium textured, drain water more slowly than sandy soils, but more quickly than clay soils. Silt soils feel like flour when rubbed between the fingers. Common silty soils are Dundee silt loam or Commerce. Clay soils contain fine-textured soil particles and can be very slowdraining. These soils feel very smooth and make a thin ribbon when moist soil is squeezed. Clay soils can hold a lot of water, but because of the small size of the soil particles, the water is bound more tightly in the soil and may not be available to the plants. Clay soil types include Alligator or Dowling clays. Transpiration: the movement of water through the leaves of the plant in exchange for CO2 used in photosynthesis; leaf temperature decreases as transpiration occurs Farmers were particularly interested in how soil water was measured, and how measurements are interpreted for irrigation decisions. To this end, we used a combination of pictures of various sensors deployed in field situations, and graphic results of actual measurements (Figure 3).

“Soil water tension maintained between -7 and -15 psi (red dashed lines) is optimal for plant growth. As the soil dries out, the soil water tension drops (green arrow). When irrigation or rainfall occurs, the soil water tension goes up quickly (the blue arrow) as water fills the soil pores.”

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Figure 3. Changes in soil water tension in a corn field irrigated with a center pivot at 0.8” every 3-4 days.

Additional topics addressed through the website included the following:    

Irrigation system calibration Measuring plant water use Measuring soil water Understanding the many type of soil water

The MIST tool was specifically designed to minimize requirements for data collection and input by the end user. To demonstrate the utility of the MIST compared to management of in-field soil moisture sensors, a static display titled “In-field sensors for measurement of soil water” was developed for use at trade shows and educational programming activities (Figure 4). This display proved beneficial for demonstrating to producers the comparative ease of monitoring soil moisture with a validated model (MIST) versus conducting maintenance and repair activities on complex measuring equipment like soil moisture sensors. The reduced potential for errors in data collection and minimal cost of setting up an account in MIST versus purchasing and installing in-field moisture sensors was a focus of the conversation that accompanied producer inquiries about the display.

Figure 4. Static display illustrating in-field sensors for monitoring soil water

Conclusions Successful extension programming relies on teaching end-users “why” along with “how” to adopt a new practice. Before we could expect corn and soybean producers to implement the MIST as a planning tool in their cropping systems, it was important to provide an explanation of the factors that contributed to the development of MIST along with the important terminology used in water management planning and the 2013 ASABE Annual International Meeting Paper

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science behind plant interaction with soil water. The combination of graphics and narrative from the AgWater website, along with the static display used during face-to-face educational programming proved successful in conveying the benefits of the MIST. The primary beneficiaries of this research are Mississippi corn and soybean producers. Understanding soil and crop water relations, irrigation scheduling, and crop water management will enable crop producers to make water use decisions based on crop needs. Water management tools and the web-based irrigation scheduler will improve the cost effectiveness of water applications, improve crop yield and quality, and reduce excess water use in corn production. Knowledge of agricultural water needs will be beneficial in developing water management policies that are economically realistic and environmentally sustainable. All Mississippians will benefit from this research through the improved management of our water resources.

Disclaimer Mention of a trade name or proprietary product does not constitute an endorsement. Details of specific products are provided for information only, and do not imply approval of a product to the exclusion of others that may be available.

Acknowledgement The authors would like to acknowledge the generous support of this research by the MS Soybean Promotion Board and the MS Corn Promotion Board.

References Rice, B., G.F. Sassenrath, H. van Riessen, A.M. Schmidt, M.L. Tagert. 2013. Implementation of the Mississippi Irrigation Scheduling Tool in a dynamic web-based format. Mississippi Water Resources Conference, Jackson, MS. Available online at: http://www.wrri.msstate.edu/publications.asp. Sassenrath, G.F., Halloran, J.M., Archer, D.W., Raper, R.L., Hendrickson, J.R., Vadas, P., Hanson, J. 2010. Drivers impacting the adoption of sustainable agricultural management practices and production systems of the Northeast and Southeast US. J. Sustainable Agriculture. 34:1–23.

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