Evaluation of Water Harvesting Techniques for Rainfed Crop Production in Jigawa State

This study evaluates the performance of different water harvesting techniques for improving rainfed crop production in Jigawa State, North West Nigeria. Jigawa State's sub-Saharan climate is characterised by short and erratic rainfall concentrated in a 90 to 120 day wet season, resulting in significant moisture stress during the growing season that severely limits crop yields. Water harvesting techniques that capture and concentrate rainfall for crop use offer a promising approach to improving water availability for rainfed farmers. This study compares the performance of four water harvesting systems, namely contour ridges, zaï pits, half-moon bunds, and stone lines, against a control treatment without water harvesting structures on experimental plots established in Dutse, Miga, and Gumel local government areas. Soil moisture at 20 and 40 centimetre depths, surface runoff, and crop yields of millet, cowpea, and sorghum are monitored over two growing seasons. Findings reveal that zaï pits generate the highest soil moisture improvement, with millet yield increases of 68 percent over control plots. Half-moon bunds show the best performance for sorghum, improving yields by 54 percent. Stone lines show modest but labour-efficient performance improvements across all crops. The study concludes that water harvesting systems significantly improve rainfed crop production in Jigawa State. It recommends zaï pit adoption with organic matter application as the highest-yield water harvesting strategy for the state's smallholder farmers.

Keywords: water harvesting, rainfed agriculture, Jigawa State, soil moisture, crop yield.