Adaptation strategies to mitigate the evapotranspiration for sustainable crop production: A perspective of rice-wheat cropping system

Abstract

Both land and water productivities are declining day by day because of depleting underground water table and unscientific conventional practices used to establish the different crops, more particularly rice and wheat cropping system in South Asia. Climate change further complicated the situations, where unpredictable rain both in terms of amount and frequency, high-temperature regimes, frequent floods, and drought adversely affected the yields in total. Evapotranspiration (ET), comprised of evaporation (nonproductive component) and transpiration (productive component), and their management are important in improving both land and water productivities. Crop water requirements during vegetative phase varied mostly due to the variation of crop canopy cover and microclimatic conditions. Efforts are being made through resource conservation technologies (RCTs) to improve the land productivity as it is closely linked with livelihood standards under the decreased or will be decreased water availability depending upon the geological conditions. RCTs partition the water/moisture from the share of an unproductive portion (E) to produce one (T) from where it could be reused for encouraging water and hence nutrient intake. Transpiration led to an increasing flow of water in plants through roots, and along with water, the inflow of the nutrients also increased, which further led to higher grain weights and grain yields. Therefore, partitioning water from E to T is the only way to improve the land productivity and hence livelihoods even at a global level with special reference to the developing countries. Set goals could be achieved only through short-duration crop cultivars, timely paddy transplantation, underground pipelines, sprinkler and drip irrigation, and zero tillage with mulch at the soil surface. Present chapter delineates the importance of ET for planning and management of water resources with RCTs with innovative strategies to manage crop ET for improving agricultural land and water productivity under changing climate at the global level.