Study on feasibility of drip irrigation in shallow ground water zones of eastern India
Although the effectiveness and economics of drip irrigation systems are well established in areas having undulating topography and water scarcity, its economics in plain areas bestowed with good quality ground water at shallow depths are not yet studied. Due to this, there is confusion among farmers as well as planners regarding the guidelines for selection and propagation of this system in such areas. This study attempts to evolve guidelines for deciding the economic threshold value of fixed cost of drip irrigation system for sugarcane crop. Nomographs have been developed to find the threshold value of economic fixed cost of drip irrigation system (exclusive of pumping unit) for a combination of variables, depth of water table, yield level under check basin irrigation, expected yield gain with adoption of drip system, irrigation requirement with check basin, and electricity charges. The perusal of nomographs shows that the factors influencing the economics of drip irrigation in order of importance are yield gain ratio, electricity charges, irrigation requirement and depth of ground water.
Study on Agricultural Water Right in Well Irrigation District in Henan Plain
China is a big agricultural province; agricultural production has been occupying a large proportion of China's industrial structure. Irrigation, as a vital link in agricultural production, is of great importance to agricultural production. With the rapid development of China's industrialization and urbanization, water use in industry and cities continues to increase. Due to the relatively high industrial benefits, many areas continue to transfer water resources to non-agricultural water such as industrial water. Therefore, China urgently needs to establish a modernized agricultural water right system to improve the sustainable development ability of agricultural water. The research on the agricultural water right in the well irrigation area of Henan plain not only saves groundwater resources but also promotes the establishment of an agricultural water right system.
Problems in Applying Optimal Irrigation Plans
Planning methodology developed by the University of Idaho allows rapid determination of least-cost irrigation-system designs to assist in rehabilitation of damaged or new systems. Procedures are applied to a small 3,000 acre (1,214 ha) irrigation system damaged in the Teton Dam flood of 1977 and optimal designs to achieve specified levels of project water-use efficiency with varying costs of water and penalties or benefits for deep percolation and runoff were selected. Energy costs for each alternative were calculated. Fear of water-right loss and the paradox in western water law that encourages conservation but provides no economic incentive severely inhibit system rehabilitation. Poor understanding of groundwater-surface-water systems and the lack of recognition of possible benefits of aquifer recharge from deep percolation of irrigation water make water users reluctant to change systems.