频繁发生的旱灾已成为限制中国西北半干旱区农业发展和生态环境建设的主要扰动因子。社会-生态系统恢复力理论可以加深人们对干旱环境中的社会学与生态学交互过程与机理的理解，提高当地系统抵御旱灾的能力。社会—生态系统恢复力是指系统能够承受且可以保持系统的结构、功能、特性以及对结构、功能的反馈在本质上不发生改变的干扰大小。目前，恢复力的研究大多停留于定性的、概念上的描述，缺乏对恢复力可操作性的实证案例研究模式。本文以甘肃省榆中县为例，从社会、经济和生态3 个角度选择水分敏感因子，构建社会—生态系统，建立了恢复力测定的定量模型，计算了过去15 年来榆中县社会—生态系统对干旱的恢复力变化，并分析了影响恢复力变化的因素。

Drought has been a crucial meteorological factor which limits the agricultural development and eco-environment construction in the northwest area of China. In the past decades, many Chinese scientists tend to explore the cause of drought from the perspective of biophysical aspects, while the accumulated body empirical evidence identifies that social system has enormous impacts on disarsters (drought) as well. Nature and mankinds are tightly linked, and they are coupled systems which can be termed as social-ecological systems. What can we do to gain a deep understanding about the interacting processes and the mechanisms bewteen nature and society, and then build a scientific foundation for drought defying decision-making? Resilience, as a new theory, provides an idea to solve this problem. Resilience refers to the capacity of a system to absorb disturbance and reorganize while undergoing changes, so as to retain essentially the same function, structure, identity, and feedbacks. Since resilience is a buffer in the social-ecological systems to the external perturbations and shocks, the management that builds resilience can sustain social-ecological systems when facing surprise, unpredictability, and complexity. Yet many studies mainly focus on description and qualitative analysis, which cannot offer practical instructions to solve specific problems, therefore, the attempt to quantify resilience of the systems, which can prevent social-ecological systems from sliding into some undesirable stable states, has become an imperative trend. Based on the statistic data and remote sensing images, the resilience of the social-ecological system to drought in Yuzhong County of Gansu Province during the last 15 years was calculated by integrating statistics approaches and GIS. The results indicate that the resilience of Yuzhong County depends on the interactions between internal factors (social, economic and natural) and external factors (aridity), and also highlight the need for local managers to be aware of how differently towns respond to drought, which is of great significance for managers to make robust managing strategies.