气象干旱对甘肃省榆中县乡村社会—生态系统的影响

干旱影响研究是干旱及半干旱地区人地关系研究的重要内容,社会—生态系统的视角为西北地区生态脆弱—贫困区的可持续性研究提供了新的思路。选取甘肃省榆中县为研究区,运用标准化降水指数、干旱经济损失估算模型和GIS分析工具,分析干旱对粮食产量、经济发展和农户家庭的影响,归纳干旱对乡村社会—生态系统的影响机制。研究结果表明：（1）1960-2015年,榆中县气象干旱程度较强,且与粮食产量呈显著正相关,尤其对榆中县南、北部山区的粮食产量影响显著;（2）气象干旱造成的经济损失具有频率高和空间分布广的特征,经济损失严重区集中在榆中县南、北部山区;（3）农户家庭受灾面积较大,农作物减产和家庭收入损失明显,气象干旱造成的粮食安全问题严重,且“纯农型”家庭收入损失和粮食安全问题尤为突出;（4）水资源利用环、产量环、收入环—生计环和经济环为干旱影响社会—生态系统运行机制的关键环节。

Impacts of meteorological drought on social-ecological system in rural areas of Yuzhong county in Gansu province

Impacts of drought play a vital role in studies on human-environment relationship in arid and semiarid regions. The assessment on the impacts of drought on social-ecological system in rural areas provides a new thinking for human-environment system sustainability of ecological fragile-poverty zone in Northwest China. The article analyses the impacts of drought on grain yield, economic development and rural household family. Then, it concludes impact mechanism of meteorological drought on social-ecological system in rural areas, applying Standardized Precipitation Index, economic loss of drought model and analysis tool of GIS. The main results include: (1) There is significant positive correlation between drought intensity and grain yield especially in the southern and northern parts of Yuzhong county, where drought intensity is high in 1960-2015. (2) Serious economy loss caused by drought characterized with high frequency and wide distribution occurs in the southern and northern parts of Yuzhong county. (3) Drought causes reduction of agricultural product and economic income obviously, and results in serious food security of rural household families that are engaged just in agriculture activity. (4) Impact mechanism of drought on social-ecological system in rural areas depends on water resource utilization loop, production loop, income and livelihood loop and economy loop.