横断山地水土要素时空分布格局与耦合特征

水土要素耦合是影响横断山地资源环境安全、防灾减灾及生态环境保育的重要因素。根据横断山地地理环境与水土要素构成特征,构建了面向农业生产空间的水土要素耦合指数,利用多源空间数据计算得到了横断山地时间序列月、年水土要素耦合指数值。研究表明:横断山地水土要素耦合格局受宏观气候-地貌格局控制,西南季风、东南季风以及横断山地纵向岭谷的"阻隔-通道"作用造就了横断山地3个水土要素耦合明显分异的区域;地形起伏度、海拔、坡度和坡位等地形指标对水土要素耦合指数都有明显影响,在微观尺度上坡度对水土要素耦合的影响最大;受两大季风气候进退、水热时空匹配、气候-植被耦合作用的影响,横断山地水土要素耦合指数年内分异明显,在6月份水土要素耦合指数最高,在年际尺度上近15年来横断山地水土要素耦合指数无明显变化趋势,以年际波动为主。本文初步揭示了横断山地耕地的水土要素耦合时空格局特征,对横断山地的水土要素调控及国土空间功能优化管理有参考意义。

The spatiotemporal distribution and coupled characteristics of water & land element in the Hengduan Mountains,China

It was one of the key factors that the coupled characteristics of water-land element which was considered to affect resource environment security, conservation ecological and strengthen disaster prevention and mitigation in Hengduan Mountains, China. The coupled characteristics of water-land element had been established for agricultural production according to the characteristics of geographical environment, water-land element in Hengduan Mountains. Furthermore, the monthly and annual time series indexes of coupled characteristics of water-land element also had been calculated by multi-source spatial data. This study showed that both the macro climate and landform were the important factors to influence the coupled characteristics of water-land element in Hengduan Mountains. Three areas with distinct differences caused by southwest monsoon, southeast monsoon and the “barrier-channel” effect of landscapes were chosen. Meanwhile, the coupled characteristics of water-land element were obviously influenced by the topographic relief, elevation, slope positions and the slope, especially. The study also founded that the coupled characteristics of waterland element with distinct differences influenced by the changing of monsoons climate, spatiotemporal water-temperature and time matching, climate-vegetation coupling effects was highest in June, compared by monthly time series. And, more remarkable, there were no distinct differences compared by annual time series of nearly 15 years. The study had revealed the spatiotemporal distribution characteristics of coupled characteristics of water-land elements. The results contribute to optimize the land function management.