喜马拉雅山中部跨境流域土地利用与覆被变化过程及其区域差异研究

Land use and land cover change in high mountain areas is the most sensitive and an important aspect to global climate change. Koshi River Basin (KRB), a trans-boundary river basin in the middle of the Himalayas and at southern margin of Tibetan Plateau, was taken as our study area. According to investigation in regional integrated, typical types and typical regional, a unified classification system in the KRB will be constructed taking accounting of differences of land-cover classification systems in China and Nepal. Multi-phase remote sensing images at different spatial scales will be interpreted by references obtained from field survey in typical types and typical land-cover changes. These land-cover types and regions sensitive to climate change and their extents and degress will be extracted by spatial analysis methods at different scales. Incorporating territorial, climate and social-economic data into Partial Least Squares regression Model and Auto-Logistic regression model, the quantitative relationship between anthropogenic and natural effects on typical land-cover types and regions will be focused to analyze their spatial difference in the KRB. Using comparing analysis method between spatial buffer zones, the differences in land-cover change, spatial variation and its driving forces at diverse thematic scales will be further studies by comparing border regions in China and Nepal, border towns on both countries, and important traffic tunnels across two countries. By comparing the influence of different climatic conditions under similar social background on land-cover change, the effects of different cultures on these cover types will be found out. It will provide case study for alpine areas on LUCC research, and promote development of the world mountain research.

兴都-库什-喜马拉雅地区是全球典型脆弱山地区域，该区土地利用与土地覆被变化(LUCC)是全球气候变化最为敏感区域之一。本研究以位于喜马拉雅山中部山地垂直带谱最为完整的跨境流域-柯西河流域为研究区，通过不同空间尺度的地面调查，综合分析中尼两国在该流域的土地覆被类型分类系统的差异，建立该地区统一的分类标准，并通过对遥感数据解译获取多期不同分辨率土地覆被数据。基于不同尺度的空间分析方法，研究该地区对于气候变化敏感的土地覆被类型和区域及变化幅度；同时结合地形、气候和社会经济数据，应用偏最小二乘法以及逻辑斯蒂模型等，探讨该地区气候变化和人类活动对于LUCC影响的定量关系；利用空间缓冲带分析法，通过边境地区LUCC空间差异对比，分析不同社会经济、文化习俗对于LUCC的影响差异以及气候背景下不同社会条件对于覆被类型的影响。为高山地区LUCC研究提供案例，促进世界山地研究发展。

以喜马拉雅中段的柯西河流域为研究区，应用3S技术，结合遥感数据、野外调查数据，构建了1992-2010年的三期土地覆被数据集；阐明了流域土地覆被构成与分布特征；研究了土地覆被的时空变化及其动因；分析了科西河流域典型区域土地利用与土地覆被变化差异；探讨了科西河流域土地利用与生态系统管理的策略。结果表明：（1）科西河流域南北翼土地覆被组成迥异，97.66%的森林分布在流域南部，而草地在喜马拉雅北翼的分布是南翼的6.7倍。（2）1992-2010年科西河流域草地扩张和收缩主要受年平均温度的影响，温度和降水的年际变化趋势对草地扩张有显着影响。农田的扩张和收缩受温度变化影响最大，人口密度与农田扩张显著相关。（3）樟木至加德满都主干公路两侧，高海拔冰川雪被减少与裸地增加显著、低海拔建设用地增加明显，流域内中尼两国主要城镇均呈现出城镇面积快速拓展。（4）针对流域土地利用与土地覆被变化情况，提出了如下的可持续管理的策略：转变粗放型农业为现代农业，实现流域农业可持续发展；加大关键物种栖息地森林生态系统的保护力度，实现生态系统服务价值的提高；建立跨境自然保护区协调管理机制。