The dynamics between irrigation frequency and soil nutrient management: transitioning smallholder irrigation towards more profitable and sustainable systems in Zimbabwe
Martin Moyo, André van Rooyen, Henning Bjørnlund, Karen Parry, Richard Stirzaker, Thabani Dube, M. S. Duarte Maya
Abstract
Successful irrigated agriculture is underpinned by answering two critical questions: when and how much to irrigate. This article quantifies the role of the Chameleon and the Wetting Front Detector, monitoring tools facilitating decision-making and learning about soil-water-nutrient dynamics. Farmers retained nutrients in the root zone by reducing irrigation frequency, number of siphons, and event duration. Water productivity increased by more than 100% for farmers both with and without monitoring tools. Transitioning smallholder irrigation systems into profitable and sustainable schemes requires investment in technology, farmers and institutions. Importantly, technologies need embedding in a learning environment that fosters critical feedback mechanisms, such as market constraints.