Impact of Irrigation on Cropping Intensity, Cropping Pattern and Productivity under Tank Commands

Providing assured, adequate and timely supplies of (irrigation) water is a sine-qua-non for increasing productivity in tropical agriculture. Irrigation impact has several dimensions. Tile most important among them are: A major shift in cropping pattern over dry less water intensive crop pattern to irrigated/high value crops. Increase in the cropping intensity and a considerable improvement in productivity of crops. All these dimensions are affected considerably by the extent of management of irrigation facilities and availability of water for crops. In an irrigation system water availability differs considerably across reaches in the command and between normal and below normal/rainfall years. In the latter situation, rich farmers supplement their well water to stabilize the agriculture. The resource-poor farmers usually have to seek the help of common source supply and if it is not fruit fed, their crop culture affects adversely. To what extent tile crop pattern, cropping intensity along with the institutional and technical factors affect productivity of farms across reaches and between different types of farmers' and between normal and deficit water supply years. This paper discusses these issues in the context of two large multi-village tanks in Tamil Nadu.