WATER USE EFFICIENCY MEASUREMENTS UNDER DIFFERENT RICE GROWING ALTERNATIVES

摘要

Food production in India comes largely from irrigated agriculture. The increase in population, in addition to climate change, will have a signifi cant impact on the available water resources. Under limited availability of water resources, water use has to be made more effi cient. Traditional paddy rice cultivation needs large amounts of irrigation water. However, alternative systems for rice growth, such as the System of Rice Intensifi cation (SRI) and Alternating Wetting Drying (AWD) have the potential for water saving. This paper presents the results of methodologies, used in the ClimaAdapt project, to obtain information about water use effi ciency (WUE) under different rice growing practices in the states of Andra Pradesh and Tamil Nadu in India. In the ClimaAdapt project, the water use effi ciency is defi ned as the yield per unit of water applied to the fi eld through irrigation and precipitation. In both the states a number of clusters, practicing different rice growing alternatives, have been selected for the study. When water is applied through irrigation canals, the amount delivered is measured using RBC fl umes. In case the water application is through bore wells, the water delivered is recorded by fl ow meters. Information about the yield under different rice growing practices is obtained through farmer information. Also yield samples are taken by the project at several locations in the clusters. The fi rst results in the ClimaAdapt project have indicated that yields increase under AWD while at the same time less water is used. The results of the ClimaAdapt project will be used by provincial governments to upscale WUE improvement programs across the provinces. An important aspect of the data collection also is its usage in models to improve irrigation water application for different rice growing techniques. This paper presents the results from measurements on of WUE for the Rabi 2012 and Kharif 2013 growing season, which are, respectively, the winter and monsoon cultivation seasons in India.