Mueller Irrigation Group

Despite the ability of soil moisture observations to significantly increase agricultural water use efficiency and provide important increases in yield and product quality, they remain under-utilized in irrigation water management in Southern Alberta. Jadler Industries and Random Acronym are producers of the FieldTracker Telemetry Device for remote field data monitoring. The FieldTracker was designed for industrial operations that require real-time observation and reporting of variables such as flow rate, water level, temperature, and water chemistry. Currently, Jadler Industries and Random Acronym are incorporating weather and soil moisture sensors into a package aimed at the agricultural industry in Southern Alberta.

Industry partners: Jadler Industries, Random Acronym
Project lead: Dr. Willemijn Appels

Site-specific irrigation management (SSIM) or precision irrigation is being advertised as a way to increase yields and water use efficiencies (WUE) in regions where irrigation water availability is limited. This project, with field work near Coalhurst, AB, aims to assess the potential for SSIM in the context of southern Alberta, Canada. Our field site is a 126 ac field with a well-defined topographic gradient and soils in loam, sandy loam, silt loam spectrum. The field is under active production, with the owner splitting irrigation applications of his center pivot between the "high" and "low" half of the field.

Since 2018, we measure weather variables, groundwater, and soil moisture dynamics at multiple locations during the growing season. These observations are complemented with occasional soil moisture surveys along a transect and UAV imagery. While soil moisture dynamics, groundwater depth, and irrigation volumes are significantly different between the two halves of the field, total biomass production and yield were uniform throughout the field, indicating SSIM was a sensible approach in this field.

We use a crop-water-soil model to assess how a threshold-based irrigation schedule would have differed from the actual irrigation management at this site and to investigate “what-if” scenarios for drier/wetter/cooler weather conditions and deeper groundwater levels. The model simulations show that uniform, high yields could have been obtained without SSIM, but that SSIM improves WUE substantially. The magnitude of the improvement is largely determined by initial conditions, which in this region are a result of fall rains and spring snowmelt, and capillary rise from the shallow groundwater. When these reservoirs are depleted, crop water demand drives the irrigation requirements and a uniform irrigation schedule can be implemented. These results illustrate that the relevance of SSIM is related to larger scale hydrological processes and may vary considerably between years.

Industry partners: Western AB Soil and Double H Feeders.

Lethbridge College (LC) and Southern Irrigation (SI) are partnering to develop a better understanding of water flow in soils with subsurface drip irrigation (SDI) systems. In their SDI operations during the warm and dry summer of 2017, SI encountered unexpected redistribution of water in various fields with SDI systems. Here, we propose a project that addresses this knowledge gap in a laboratory, computer, and field setting.

For the laboratory experiment, three large (6x3x1.2 m) soil bins will be constructed and filled with three different local soils. An alfalfa crop will be seeded in each of the bins. When the crop is established, sixteen irrigation scenarios will be tested. We will collect data on the horizontal and vertical distribution of water with soil moisture sensors positioned at various depths and distances around the SDI lines and emitters. With these data, we will calibrate a HYDRUS-3D model to generalize the laboratory results to other soil and crop types. Based on the laboratory and model simulation results, irrigation management plans will be designed for three field locations with SDI systems. At these field locations, soil moisture dynamics will be monitored throughout the growing season. We will evaluate the extent to which the complexity of the real world interferes with the soil moisture dynamics as observed in the controlled laboratory settings.

We expect the results from the laboratory and field experiment to improve installation and management recommendations of SDI systems in western Canada. Benefits for SI include development of evidence-based installation and scheduling recommendations and having access to an SDI demo for their staff and customers. Benefits for LC include access for researchers and students to working with SDI technology (a first) as well as collecting data for its larger irrigation research program, which focuses on improving water use efficiency of the irrigated agriculture sector. By combining research grade and commercial soil moisture technologies, the project will contribute to the incorporation of new soil physical findings in on-farm irrigation water management.

Funded by: NSERC and industry partner Southern Irrigation

MSc project of Danielle Crawford (graduate of Ecosystem Management degree – Lethbridge College) under supervision of Dr. Willemijn Appels and Dr. Kenny Corscadden. The goal of the project is to quantify and explain the variability of plant available water in various management zones of a potato field.

Funded by: an NSERC Discovery grant (Dr. Kenny Corscadden, Dalhousie University) and the Mueller Applied Research Chair with in-kind support by Alberta Agriculture and Forestry.

Decision-making for crop management can be improved with detailed, frequent observations of soil, weather, and plant conditions. The temperature of a crop reveals information on its well-being: the cooler the crop is compared to the air temperature, the more successful it is at obtaining water. In this project we built and tested a wireless infrared camera to measure the temperature of plants in an agricultural field. From this data, we developed a computer program that translates the images into an indicator of water stress level that is useful for irrigation scheduling.