云南边境山区景观生态风险时空演变及其影响因素

Temporal and spatial variation of landscape ecological risk and influential factors in Yunnan border mountainous area

探究边境山区景观生态风险时空演变特征,揭示自然与人类活动对景观生态风险的影响,对维护国际生态安全和保障区域生态系统的稳定性具有重要意义。以云南25个边境县为例,采用2000、2010、2020年三期土地利用数据,基于景观格局指数构建了景观生态风险评价模型,并分析了风险的时空演变特征,利用地理探测器测度了自然、可达性和社会经济因素对景观生态风险的影响程度。结果表明:2000—2020年研究区景观类型以林地和耕地为主,林地、草地、湿地、冰川和永久积雪面积减少,耕地、灌木地、裸地、人造地表、水体面积增加。景观生态风险平均值持续上升,在空间上表现出显著的自相关性。研究区以较低生态风险、中等生态风险为主,低生态风险、较低生态风险、高生态风险区面积减少,中等生态风险、较高生态风险区面积增加。年降水量、年均气温、距城镇距离、人口地理集中度指数、人口经济地理集中度不一致指数是影响区域景观生态风险的主要因素,在交互探测中年降水量与年均气温、人口地理集中度指数与人口经济地理集中度不一致指数、年降水量与人口地理集中度指数交互作用对景观生态风险的影响较大。

It is of great significance to explore the temporal and spatial evolution characteristics of landscape ecological risk in border mountainous area and reveal the impact of natural and human activities on the landscape ecological risk,so as to maintain international ecological security and guarantee the stability of regional ecosystem.Based on the land use data in 2000,2010 and 2020 of 25 border counties in Yunnan Province,a landscape ecological risk assessment model was established with landscape pattern index.The spatio-temporal evolution characteristics of landscape ecological risk were analyzed,along with the impacts of natural,accessibility,and social-economic factors on the landscape ecological risk were measured by the geographical detector.The results showed that the landscape types in the study area were mainly forest land and cultivated land from 2000 to 2020.During the same period,the area of the forest land,grassland,wetland,glacier and permanent snow decreased,while the area of the cultivated land,shrub land,bare land,artificial surface and water increased.The mean value of landscape ecological risk increased continuously and showed significantly spatial self-correlation.The ecological risk was mainly at lower and medium level among the area,yet the proportion of land in low,lower and high levels of ecological risk decreased,while those in the medium and higher level increased.Annual precipitation,annual average temperature,distance from town,population geographic concentration index,and population economic geographic concentration index of inconsistency were the main factors affecting regional landscape ecological risk.The interaction between precipitation and average annual temperature,population geographic concentration index and population economic geographic concentration index of inconsistency,and annual precipitation and population geographic concentration index had greater impact on landscape ecological risk.