西孟加拉邦印支-恒河下游平原作物轮作以提高水分利用和营养生产力（英）

ISSUE NO. 358 JUNE 2022© 2022 Observer Research Foundation. All rights reserved. No part of this publication may be reproduced, copied, archived, retained or transmitted through print, speech or electronic media without prior written approval from ORF.Occasional Paper201Attribution: Archit Lohani, “Countering Misinformation and Hate Speech Online: Regulation and User Behavioural Change,” ORF Occasional Paper No. 296, January 2021, Observer Research Foundation.Attribution: Preeti Kapuria and Saon Banerjee, “Crop Shifting for Improved Water Use and Nutritional Productivity in the Lower Indo-Gangetic Plains of West Bengal,” ORF Occasional Paper No. 358, June 2022, Observer Research Foundation.Crop Shifting for Improved Water Use and Nutritional Productivity in the Lower Indo-Gangetic Plains of West BengalAbstractThe challenge for agriculture is to meet rising demand for food while dealing with climate change and natural resource constraints. This paper takes the case of cereal production in the lower Indo-Gangetic plains in the state of West Bengal, India, and examines the implications of various crop-shifting scenarios on consumptive water demand and nutrient production. The analysis finds that by replacing summer crop (Boro rice) in each district with maize, it is possible to reduce demand for irrigation water and improve the production of macro and micro nutrients. This can have significant implications, as the sustainability of future crop production depends on the availability of groundwater—a critical resource for self-sufficiency of grain production in the region.Preeti Kapuria and Saon Banerjee3IntroductionAccess to safe and sufficient water is essential to food security and nutrition. In recent years, water resources in many parts of the world have come under severe threat because of the depletion and degradation of habitats. Some of these threats are the direct result of a growing demand for food and the associated changes in dietary patterns.1Globally, agriculture is by far the largest user of freshwater withdrawals, at an estimated 70 percent;2 these withdrawals are almost entirely used for irrigation. In turn, providing 40 percent of the irrigation3 is groundwater—a critical freshwater resource that can be extracted even during the dry season, unlike surface waters.India is the world’s largest consumer of groundwater with more than 60 percent of the nation’s irrigation supply and around 85 percent of drinking water supplies provided by this resource.4 Today, in many important agricultural regions across the country, groundwater reserves are fast getting depleted. Although the increase in cropping intensity has provided for food production gains, it has also resulted in high rates of extraction and, consequently, the depletion of aquifers. Estimates say that by 2025, the overall cropping intensity will reduce by up to 20 percent throughout the country and by almost 68 percent in the regions projected to have low future groundwater avai