基于InVEST模型和莫兰指数的甘肃省生境质量与退化度评估

生境质量的高低与土地利用/土地覆被类型为生物多样性提供的栖息地适宜性有直接关系，尤其是农业开发活动、城市、道路等严重威胁生境质量，为了评估西北生态脆弱地区生境质量和退化程度，该研究以甘肃省为例，应用INVEST模型和莫兰指数对甘肃省生境质量和生境退化空间特征进行分析，明确其热点区域，并探讨了生境质量与退化度及其热点与各类自然保护地的关系。结果表明：甘肃省生境质量从南到北逐渐下降，而生境退化度从北到南逐渐升高，自然生态条件好的区域这种变化主要取决于人类活动的位置和强度；甘肃省生境质量热点区面积占到全省国土面积的25.59%，高于全省自然保护地面积占比，形成了保护空缺，甘肃省生境退化热点地区面积虽然不高，但多为自然生态条件较好的区域；各类保护地中，国家公园是各类保护地类型中生境退化度最低的类型，保护水平相对较低的其他保护地类型在生境质量和退化程度上表现出相反的结果。研究结果对精准实施生物多样性保护战略和生态系统管理决策具有重要意义。

Assessment of habitat quality and degradation degree based on InVEST model and Moran index in Gansu Province, China

Abstract: The habitat quality is directly related to the habitat suitability provided by land use/land cover types for biodiversity. Habitat quality is seriously threatened by human activities, especially agricultural development activities, cities, roads. In order to assess the habitat quality and degradation degree in the ecologically fragile areas of Northwest China, taking Gansu Province as an example, based on the high-resolution (30 m) land use/ land cover type data and various types of natural reserve data, habitat quality module in InVEST software was used to evaluate the habitat quality and degradation, and both spatial analysis and local Moran''s I were used to identify the hot spots and cold spots of habitat quality and degradation. On this basis, the relationship between habitat quality and degradation and the hot spots and all kinds of natural protected areas were analyzed. The results showed that: 1) The habitat quality was gradually decreasing from south to north, while, the habitat degradation was gradually increasing from north to south in Gansu Province. In the south and east of Gansu Province, the habitat degradation was also high, due to the strong disturbance of human activities, even though the habitat quality generally presented well. The habitat quality and degradation depended mainly on the location and intensity of human activities. The combination of habitat quality and degradation can more truly represent the current level of habitat protection. 2) The hot spots of habitat quality accounted for 25.59% of the total land area of Gansu Province, and most distributed in the south of Gansu Province, indicating a consistent with the proportion of natural conservation areas in Gansu Province. Most areas showed better natural ecological conditions, due to there was not many areas of degradation in hot spots. A recommendation can be made during this time, to turn the biodiversity conservation into the most endangered sites in the future; 3) In all types of protected areas, the habitat degradation of National Park was the lowest, whereas, that of other protected areas was the highest. The coverage area of hot spot in habitat quality was much higher than that of habitat degradation. The coverage rate of hot spot significantly varied in the different types of protected areas. The coverage rate of hot spot for habitat degradation was also the highest in the protected areas, while that for habitat quality dominated in other types of protected areas. A suggestion was made during this time that the strategy planning of nature reserve can be focused on other protected areas, in order to strengthen the ecological restoration in other nature reserve, and further to reduce the interference of human activities. The findings can offer the accurate implementation of biodiversity conservation strategies and ecosystem management decisions in the western China.