Development of A Spatial Decision System for Irrigation Management

Abstract

Spatial decision system provides a framework for integrating database management systems, analytical models, and graphics to improve the decision-making process from a farm-scale to a regional level. In this study, a graphical user interface for irrigation management has been developed with the support of a geographical information system (GIS) customization using Visual Basic for Application (VBA). Inverse distance weighted (IDW) method is employed to interpolate spatial inputs through an embedded environment provided by the GIS for customization with VBA technique. The developed Interface was used to analyze, simulate, handle, and integrate the irrigation management's spatial data. It can be used effectively from a farm-scale to a regional level and temporal data with interpolation techniques to generate thematic maps of rainfall, effective rainfall, reference evapotranspiration (ETo), crop evapotranspiration (ETc) using weather, crop, and soil data. The tool allows visualization of the spatial distribution of water requirements in the specified region and facilitates the localization of any discrepancies in water management, indicating whether interventions are required. Finally, interface was applied to estimate spatial irrigation water requirement to provide output, i.e., spatial maps of rainfall, effective rainfall, daily ETo, daily ETc, and net irrigation requirement (NIR). ETo was higher at Bhopal, Tikamgarh and Jhansi and lowered at Raisen and Sagar. The generated NIR map shows that the area nearby Khurai station has a higher irrigation requirement. On the other hand, the area covered by Begumganj, Sironj, Tikamgarh, and Banda has lower irrigation requirements. This information may help irrigation management's decision-making from a farm-scale to a regional level in the Betwa River Basin, India.