岷江上游聚落生态位内部土地利用变化特征

Land Use Change Characteristics of Settlement Ecological Niche in the Upper Reaches of Min River

山区人类生产和生活对土地利用的影响主要集中在聚落生态位内,以山区聚落生态位为研究单元,可有效揭示山区微观尺度土地利用的动态变化过程和人地作用机制。利用遥感资料和GIS技术,研究1999—2009年岷江上游干旱河谷区聚落生态位内部土地利用时空分布及其变化特征,研究结果表明：（1）10年间聚落生态位内耕地显著减少,而草地和林地明显增加;（2）聚落生态位内土地利用在海拔2001~2900 m、坡度15°~35°分布最为集中,在坡向上呈现南坡高于北坡,东坡高于西坡的特征;（3）聚落生态位内高山区土地利用结构趋于有序,而低山区-高半山区土地利用结构趋于无序。岷江上游聚落生态位内部土地利用正处于快速调整阶段,耕地呈现出明显的非农化特征（耕地→草地、耕地→生态林、耕地→经果林）,这种土地利用变化主要是聚落人口空心化、生态保育政策和比较利益共同驱动作用的结果。

The impacts of human production and life on land use in mountainous area mainly focus onsettlement ecological niches, taking the settlement ecological niche as the basic research element couldeffectively reveal the changing process of land use in micro- scale in mountainous area and the actionmechanism between human and land. Temporal-spatial distribution and change characteristics of land use inthe dry valley settlement ecological niche of the upper reaches of Min River from 1999 to 2009 were studiedbased on remote materials and Geographical Information System technology. The results showed that：（1） thefarmland areas in the settlement ecological niche significantly decreased during the ten years, but the grasslandand forest areas increased;（2） the land use in the settlement ecological niche was concentrated within thealtitude range of 2001-2900 m and the gradient of 15o-35o, and the land use area of the south slope was higherthan that of the north slope, and the land use area of the east slope was higher than that of the west slope;（3）the land use structure in high mountainous area in the settlement ecological niche tended to be well-aligned,but the land use structure in low-high mountainous area tended to have a disorder state. The land use in thesettlement ecological niche in the upper reaches of Min River was in a quick adjustment stage, the farmlandshowed obvious non-agricultural characteristics, such as farmland changing to grassland, ecological forest andeconomic fruit forest. The main reason was attributed to the joint action of population decrease, ecological conservation policies and comparative benefits.