Assessing irrigation scheme performance using remote sensing for improving water management in Burkina Faso

Given the increasing pressure on water for agricultural irrigation, coupled with unpredictable climate conditions, and with the lack of resources to carry out regular performance assessments, the use of cost-effective methodologies is critically important to improve irrigation water management and sustain crop production in irrigation schemes. In this study, a remote sensing-based methodology was developed to assess the spatial and temporal performance patterns of a 1200-ha irrigation scheme, the Kou Valley irrigation scheme (KVIS) during two consecutive cropping seasons (2013 and 2014). The analysis of the KVIS irrigation performance indicated varying spatial performance depending on the year, crop, and the crop's geographical position in the irrigation scheme. A gradient of spatially varied relative evapotranspiration was observed across the scheme resulting in four main areas according to water stress levels (from well-watered areas to moderately, highly and very highly water-stressed areas), with the uniformity of water consumption being fair to good. Results also showed large spatial variation of CWP during the study years, with sweet potato achieving relatively good performance compared to the two other crops. Distance between field and the irrigation scheme inlet (DPSI), field elevation, sand and silt contents, soil total nitrogen, extractable potassium, and zinc were the main biophysical factors affecting rice ETa and CWP. The importance of each of these variables in explaining the variability in ETa or CWP varied according to the modelling approach although DPSI was the most-contributing variable. Our findings ascertain the potential of remote sensing-based methodologies to serve as a basis for improved irrigation water management in decision support tools in data-scarce and resource-limited environments.