Water Footprint in Rice-Based Cropping Systems of South Asia

Abstract

Global population is increasing at an alarming rate, need to produce more food grains with the shrieking infinite natural resources, and water security is a major problem on the planet. In the agriculture various level of water pollution due to urbanization, industrialization, changing dietary habits, higher trends of food wastage, etc., its management is a need of hour. In the present scenario reducing the water footprint (WF) for the future generation is a key factor for the society welfare and sustainability on the planet, and agriculture is a big sector that is exploiting the quality water on the earth. There is an urgent need to focus on the ecofriendly water saving approaches with efficient use in the agricultural systems. Rice–wheat cropping system (RWCS) is covering a major area ~12.5 Mha in South Asia; it is using a huge amount of water compared to the other agriculture systems. Scientists across the region are working for reducing the share of the WFs in agriculture and in this regard, many technologies known as resource conservation technologies (RCTs) are advocated in the region. Among different RCTs—laser land levelling (LLL), short duration cultivars, timely transplanting of rice, irrigation scheduling through tensiometers, direct seeding of rice, crop diversification, raised bed planting, mechanical transplanting are the main technologies recommended for the RWCS. Hence, these technologies are not universally effective in reducing the WFs, hence, their proper selection at farmer’s fields in their conditions is a must for reducing the WFs. Further, among all, only two, viz., short period cultivars and appropriate transplanting reduce the drainage (which could be reused) share instead of reducing the share of evaporation (which cannot be reused). Further, as evaporation reduced its reduced share diverted to transpiration which further improves the nutrient inflows and finally yields. This chapter is focused on the integrated invented, tested approaches, those are recommended for the south Asian farmers’, and practicing in the rice-based cropping systems. It can help in reducing the WF to improve the land and water productivity for their livelihoods security.