生态系统为人类生存和发展提供必要的物质保障，而全球生态系统的服务功能却在逐渐退化，权衡经济发展和社会保护显得至关重要。结合土地利用/土地覆盖变化对生物多样性进行空间上的分析成为研究热点和重点。拉市海是云南最重要的高原湿地，还是候鸟越冬的理想聚集地，迁徙候鸟从青藏高原南飞的第一个台阶，2005年被列入国际重要湿地名录，具有重要的生态价值。本文通过对拉市海流域2015年SPOT6卫星影像进行解译得到了当前土地利用图层，并结合威胁因子图层、威胁因子数据、威胁因子敏感度数据对拉市海流域当前的生境退化程度、生境质量进行了评价。对2015年土地利用图进行空间统计分析得到各土地利用类型面积占比顺序依次为林地、水田、草地、灌木林、湖泊水库、农村居民点、城镇用地、滩地、旱地、道路、其他建设用地、河流和养殖水面。运行InVEST模型输出结果为生境退化度得分和生境质量得分，通过ArcGIS软件对输出结果采用自然间断点和等间隔方法进行重分类，得到可供直观分析的生境退化度空间分布图和生境质量空间分布图。从生境退化度得分情况来看，得分在0~0.0029范围内的为最低退化等级，其面积占了流域总面积的46.01%，得分在0.19~0.42范围内的为严重退化等级，仅占总流域面积的2.93%，说明流域内生境退化度较低，受到人类威胁因子影响较小。从空间分布情况来看，在拉市海、文海、文笔、吉子水库四块水域周围形成了四个退化带，这些区域未来生态保护压力大。生境质量得分是一个0~1的综合指标，1表示生境完全适宜生物生存和繁衍。从结果来看，超过中等质量等级（0.4~0.6）的生境面积为总面积的92.65%，超过较高生境质量等级（0.6~0.8）的生境面积为总面积的66.36%，最低质量等级的区域主要分布在文笔水库周围和拉市海湿地周围。

拉市海流域;   生境质量评价;   InVEST模型;     生物多样性

Ecosystem provides the necessary material guarantee for the survival and development of mankind, but the service and function of the global ecosystem is gradually degraded. Balancing economic development and ecosystem protection is becoming more and more important. Understanding biodiversity in spatial with change of land use/land cover(LULC) has become a research hotspot. Lashihai is one of the most important plateau wetlands in Yunnan Province and is an ideal gathering place for migratory birds in winter. It was included in the list of important wetlands in the world in 2005. This paper selected SPOT6 remote sensing images of Lashihai in the year of 2015 as basis data, and interpreted remote sensing images to a map of land use/land cover. This paper combined the LULC map and the sensitivity of LULC types to each threat, spatial data on the distribution and intensity of each threat to analyze the degradation and quality of the habitat. We analyze spatial statistical characters of LULC map, and find that the order of proportion of each type of LULC is woodland, paddy field, grassland, shrub, lake and reservoir, rural residential, urban land, beach wetland, dryland, road, other constructive area, river and water aquaculture. Running InVEST model, we get the scores of degradation and quality. We reclassify the degradation and quality scores through ArcGIS software to obtain visual spatial distribution of habitat degradation and quality.  Score in 0~0.0029 is defined as lowest degraded level, which is 46.01% of total watershed area. Score in 0.19~0.42 is defined as severely degraded level, which is 2.93% of total watershed area. As for spatial distribution, four wetlands are surrounded by degenerate bands, where protection pressure will be high in the future. Habitat quality score is a comprehensive index of 0~1, 1 indicates that habitat is suitable for animals and plants to survive and reproduce.  Results show that the area above medium quality level (0.6~0.8) is accounted for 92.65% of the total area, the area above higher habitat quality level is accounted for 66.36% of the total area. The area of lowest level of quality is mainly distributed around Wenhai and Lashihai.

Lashihai watershed;   habitat quality assessment;   InVEST model;   Biodiversity

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