Physio-Climatic and Socio-Economic Suitability Assessment of Alternate Wetting and Drying (AWD) Irrigation Water Management in Bangladesh

Alternate wetting and drying (AWD) irrigation system is a water-saving, methane emission-reducing, and cost-effective technique for rice cultivation but field level adoption rate is very slow in Bangladesh. To accelerate the AWD irrigation system, suitable areas and seasons are very important. The main objective of this study was to classify the suitability of AWD irrigated rice area of Bangladesh. The methodology combined physical parameters (slope, soil texture, moisture, drainage, permeability, pH) and climatic parameters (rainfall and temperature) to assess the physio-climatic suitability of AWD. In addition, irrigations pump density, farmers’ wealth index poverty, arable land and farmers ratio, farm holding size and literacy rate were selected as socio-economic suitability parameters. The relevant data were collected from respective sources in statistical, geospatial and satellite imagery formats. The collected dataset was preprocessed, converted into the same formats and spatial resolution, interpolated, reclassified and scored according to the influences to assess the suitability of the AWD irrigated rice area estimation. The dataset used was from 2000 to 2020 and prepared the weighted overlay methods. The developed method has been applied with significance weights of different controlling parameters for assessing AWD irrigations suitable land and time for rice cultivated area. The result showed that physically the country was highly suitable (up to 36.76%) and moderately suitable (up to 62.46%) for all 3 different rice growing seasons. Physio-climatically, the boro rice season was highly suitable (83.36%), amon rice season was moderately suitable (55.2%) and Aus rice growing season was lowly suitable (78.92%) for AWD irrigation. On the other hand, socio-economically the country was moderately suitable (78.45%). Physio-climatically and socio-economically the country was suitable for AWD irrigation practices which could be a great potential tool to mitigate climate change challenges.