CNH-EX: Monsoon Harvests: Assessing the Impact of Distributed Storage Tanks on the Vulnerability of Subsistence-Level Agriculture in Tamil Nadu, India

该项目的总体目标是更好地了解雨水收集池(池塘)如何在印度南部泰米尔纳德邦缺水的农业区加强蓄水和增加地下水补给。这样做的目的也是为了加强我们对这些水箱灌溉系统在依赖它们的村庄社区内发挥的作用的了解，特别是在最大限度地减少社会、经济和环境脆弱性方面。为了实现这些目标，项目组将访问各种数据源，获取有关气候、土地使用、水箱数量及其位置、水治理系统、地下水消耗、水箱提供的水量以及劳动力市场的信息。将确定泰米尔纳德邦坦克灌溉系统多年来下降的地区，并将其与持续使用坦克的地区进行比较。为了了解与水箱相关的蓄水动态，项目组将在确定的一系列水箱中放置水位传感器，这些水箱将提供有关整个季风和旱季的水存储的连续数据。假设这些水箱提供的生态和经济效益，如果得到适当的维护和有效的社区治理结构，可以使这些自给自足的农业社区不那么容易受到区域年度季风变化的影响，特别是在气候变化和地下水迅速枯竭的情况下。印度泰米尔纳德邦南部的马杜赖地区面临着严重的缺水问题，因此需要广泛的灌溉系统。近几十年来，随着泰米尔纳德邦种植面积的增加，对灌溉用水的需求也在增加。随着这种增长，地下水供应日益枯竭。因此，现在人们认识到需要一种更可持续的方式来提供灌溉用水。水管理的一个有希望的趋势是重新评估和恢复使用使用水箱系统的较旧的、当地规模的灌溉做法。这些水箱本质上是用来收集当地雨水的小型水库，收集用于地表水灌溉和地下水补给的水，数千年来一直是印度灌溉和饮用水的来源。目前的项目将侧重于提高我们对与这些小型灌溉系统相关的蓄水和地下水补给动态的了解，以及这些系统对相关村庄的重要性。该项目将使人们更好地了解在严重缺水地区，传统的雨水收集做法如何能够增加饮用水和灌溉用水的获取。由于全世界8亿人生活在缺水问题持续存在的地区，印度在雨水收集和地下水补给方面获得的更多了解将不可避免地具有跨文化价值，并可能应用于从撒哈拉以南非洲到美国西南部的一系列地区。该项目开展的研究将为在不同文化背景下更多地探索地方一级的水管理系统和机构奠定基础。

The overall objective of this project is to better our understanding of the ways in which rainwater harvesting tanks (ponds) are able to enhance water storage and increase groundwater recharge in water-scarce agricultural areas of Tamil Nadu in southern India. The intent is also to enhance our knowledge of the role that these tank irrigation systems play within the village communities that depend on them, especially with respect to minimizing social, economic and environmental vulnerability. To achieve these goals the project team will access a variety of data sources, obtaining information about climate, land-use, the number of tanks and their locations, water governance systems, groundwater depletion, the amount of water contributed by the tanks, and labor markets. Areas in Tamil Nadu in which tank irrigation systems have declined over the years will be identified and compared with areas where use of the tanks has persisted. To understand the water-storage dynamics associated with the tanks, the project team will place water level sensors in an identified series of tanks that will provide continuous data regarding water storage throughout the monsoon and dry seasons. It is hypothesized that the ecological and economic benefits provided by these tanks, when adequately maintained and with effective community governance structures, can make these subsistence-level farming communities less vulnerable to variations in the region's yearly monsoons, especially in the face of climate change and rapid groundwater depletion. The Madurai region of southern Tamil Nadu, India, faces issues of acute water scarcity, making extensive irrigation systems necessary. As the areas under cultivation in Tamil Nadu have grown in recent decades, so has the demand for irrigation water. With this growth, groundwater supplies have become increasingly depleted. As such, the need for a more sustainable means of providing irrigation water is now being acknowledged. A promising trend in water management has been to reassess and revive the use of older, local-scale irrigation practices that utilize tank systems. These tanks, which are, essentially, small reservoirs used for local rainwater harvesting, collect water for both surface water irrigation and groundwater recharge, and have been a source of irrigation and drinking water in India for thousands of years. The current project will focus on improving our understanding of the dynamics of water storage and groundwater recharge associated with these small irrigation systems, and the importance of the systems to the associated villages. This project will lead to a better understanding of the ways in which traditional rainwater harvesting practices can increase access to both drinking and irrigation water in regions of acute water scarcity. As 800 million people worldwide live in regions where water scarcity issues are an ongoing problem, the greater understanding that is gained in India with regard to rainwater harvesting and groundwater recharge will inevitably have cross-cultural value and potential application to a range of regions, from sub-Saharan Africa to the southwestern United States. The research carried out in this project will lay the groundwork for additional explorations of local-level water management systems and institutions in a variety of cultural contexts.