摘要
基于西南及周边地区1960—2013年气象观测资料,分析了近54年西南地区水稻生长季水分亏缺率时空变化特征,探讨了环流异常、地理环境与水分亏缺率时空变化的关系。结果表明:在空间格局上,由于受气候条件和地理环境影响,东部丘陵区水分亏缺相对较多,云贵高原水分供给相对充足,且水分亏缺区和盈余区分别呈现出"一带两中心"的分布特征;在变化趋势上,近54年西南地区水稻水分亏缺呈现"整体变干、局部变湿"的空间格局,"甘孜—钦州"一线以南地区水分亏缺率呈现增大趋势,"甘孜—钦州"一线以北地区水分亏缺率呈现"增大—减小相间"的分布格局;在影响因素上,NAO、ENSO与西南地区水稻水分亏缺率变化具有相关性。在NAO正相位时,除广西丘陵区沿海地带部分站点水分亏缺率呈下降趋势外,整个地区干旱化程度加剧;在厄尔尼诺年,西南地区水分亏缺率存在地域分异,横断山区、四川盆地和云贵高原水分亏缺率呈上升趋势,东部丘陵区水分亏缺率则呈下降趋势。全球变暖背景下,西南地区水稻水分亏缺率逐年增加,对灌溉蓄水依赖明显,增大了区域农业脆弱性。
Many parts of China have experienced frequent and severe droughts over the past century, particularly southwestern China. These severe droughts had substantial ecological and socioeconomic impacts. Cognition and awareness of water deficit is important to understand the supply-demand situation, ensure rational utilization of water resources, and minimize the adverse impacts of drought. This study analyzed the spatiotemporal variation of water deficit rates during the rice growing seasons in southwestern China over a period from 1960 to 2013. The Penman-Monteith model was used to estimate the reference evapotranspiration of rice during the growing seasons and a simple approximation following the method developed by the USDA Soil Conservation Service was used to compute the effective precipitation. Pearson＇s correlation coefficients were then used to evaluate the linear relationships between water deficits and oscillation factors, although the model data frequently underestimated non-linear information, and synthetic analyses were used to further reveal the characteristics of water deficit anomalies in response to fluctuations in the North Atlantic Oscillation （NAO） and El Ni？o Southern Oscillation. Furthermore, we analyzed the relationships between spatial patterns of rice water deficits and geographical environments and attempted to identify the most important explanatory drivers for the spatial distribution of water deficits in southwestern China. The results showed that the amount of rice water deficiency was negative for the growing seasons in the study area during 1960-2013, which means that water surpluses persisted in aggregates. The spatial distribution of rice water deficiency was affected by climatic and geographic factors. Rice water deficiency presented a clear pattern that was high in the eastern hilly region and low in the Yunnan-Guizhou Plateau. Water deficit and surplus in some regions displayed a ＂one stripe with two centers＂ pattern, e.g., eastern hilly region, east Sichuan, and easter
出处
《生态学报》
CAS
CSCD
北大核心
2016年第18期5798-5808,共11页
Acta Ecologica Sinica
基金
国家重点基础研究发展计划项目(2012CB955402)
地表过程模型与模拟创新研究群体科学基金项目(41321001)
关键词
气候变化
水分亏缺率
水稻
时空变化
西南地区
climate change
water deficit rate
rice
spatiotemporal variation
southwestern China
