西辽河上游生境质量时空演变特征与影响机制

西辽河上游是我国辽河流域的重要水源地，其生境质量的好坏关系到下游流域生态安全和人类福祉。然而针对西辽河上游生境质量及其影响机制的研究还有待深入。基于ArcGIS软件、InVEST模型，定量分析了西辽河上游1980—2018年土地利用和生境质量的时空演变特征；并进一步探究了西辽河上游生境质量变化的主要驱动因子。结果表明：(1)1980—2018年，西辽河上游草地面积较1980年下降了21.93%,其中大部分转化为林地(7719.09 km²)、耕地(6014.90 km²)和裸地等(3025.71 km²)等，各斑块的空间分布异质性增加；尽管研究期内，林地面积较基期大幅度提升了48.67%,但全区域平均生境质量指数由0.74下降到0.72。(2)该地区无论在区域本底环境和区域社会经济发展水平上，均对于西辽河上游的生境质量改善产生了积极作用，年均气温(0.218)、降水(0.229)、地区生产总值(0.850)和受教育程度(0.132)与生境质量指数呈现较为明显的正相关关系；然而，本地区城镇化速率(-1.137)、景观分离度...

Characteristics of spatio-temporal evolution and influence mechanism of habitat quality in the upper reaches of the West Liaohe River

The upper reaches of the West Liaohe River is one of the most important water sources of the Liaohe River Basin in China, and the quality of its habitat is directly related to the ecological security and human well-being of the downstream basin. However, the relevant studies on the habitat quality about the upper reaches of the West Liaohe River is still relatively scarce, and further studies on its influencing mechanism also needs to be conducted. Based on the models of ArcGIS and InVEST, our study quantitatively analyze the spatial and temporal evolution characteristics of land use and habitat quality on the upper reaches of the West Liaohe River from 1980 to 2018, what is more, we also further explored the main driving factors which caused the habitat quality changes during the 38 years. Several results have showed that:(1) From 1980 to 2018, the grassland patches area in the upper reaches of the West Liaohe River decreased by 21.93% compared with that in 1980, most of which has been converted into forest (about 7719.09 km²), farmland (about 6014.90 km²) and bareland (about 3025.71 km²). Meanwhile, the spatial heterogeneity of the land use patches in the study area has increased. Although the area of forest land patches increased by 48.67% compared with the that in 1980, the average habitat quality index of the whole area has dropped from 0.74 to 0.72. (2) Over the past 38 years, both the regional background environment and the level of regional social and economic development had played a positive role on the improvement of habitat quality in the upper reaches of the West Liaohe River. The factors, such as the annual average temperature, the precipitation, and the level of education, have shown significantly positively correlated with the habitat quality index, which regression coefficients were described as 0.218, 0.229, 0.850, 0.132 respectively. However, the factors, such as the urbanization rate, the splitting index, and the expansion of urban roads, have showed a negative relationship with the habitat quality index, which regression coefficients were expressed as -1.137, -0.532, and -0.394 respectively. It could be seen that the intensification of human activities caused by the rapid urbanization is an important inducement leading to the deterioration of the regional habitat quality. The study aimed to balance regional development and ecological protection about the upper reaches of the West Liaohe River. Moreover, it aimed to provide scientific and technological support for the sustainable development of ecologically fragile areas represented by semi-arid agro-pastoral ecotone.