Rainwater harvesting agriculture: An integrated system for water management on rainfed land in China's semiarid areas

Rainwater harvesting agriculture (RHA), which was first developed by scient ists in Gansu province over a decade ago, is an integrated system for water management on rainfed land in semiarid areas. This system consists of thre e main components including rainwater harvesting system, water-saving irrig ation system, and highly effective crop production system. Its main functio n is to provide farmers in water-limiting environments with access to the w ater needed to meet domestic and agricultural water needs. The preliminary implementation of RHA in Gansu and other provinces in northwest China sugge sts that RHA has the potential to improve performance in rainfed farming sy stems and to address environmental problems such as soil erosion. The small -scale and low cost of RHA systems make application by household farmers si mple. However, to be successful RHA needs to be integrated in a comprehensi ve agricultural-management system; i.e. management of RHA must be combined with other agricultural technologies and management practices. In addition, the spread of RHA over large areas entails consideration of a range of tec hnological, agrohydrological, ecological, social, cultural, economic, and p olitical factors. In particular, there is a need to provide training and ex tension services to farmers, to develop and disseminate more effective and affordable types of RHA technologies as alternatives and to design and deve lop alternative policy instruments and social institutions that facilitate adoption of RHA practices.