鄂尔多斯-榆林地区景观生态风险评价及其驱动因子分析

Landscape Ecological Risk Assessment and Its Driving Factor Analysis in Ordos-Yulin Area

[目的]对鄂尔多斯—榆林地区(简称“鄂榆地区”)景观生态风险评价及驱动因子进行分析,为该区生态环境治理、修复以及生态安全格局的构建提供科学依据。[方法]以2000,2010和2020年的鄂榆地区土地利用数据为基础,运用ArcGIS 10.2和Fragstats 4.2等软件,基于景观干扰度和景观脆弱度构建景观生态风险评价模型,从时间和空间上对鄂榆地区景观生态风险进行动态分析,并利用地理探测器方法探测其变化的驱动因素。[结果]①草地、耕地和未利用地为鄂榆地区主要的土地利用类型,其中在2010—2020年土地利用变化强度和速度最为活跃,草地为主要的转入、转出类型;②在2000—2010年,中生态风险、较高生态风险和高生态风险地区面积呈现扩张趋势,低生态风险、较低生态风险呈现收缩趋势。在2010—2020年,中生态风险、较高生态风险和高生态风险低面积呈现收缩趋势,而低生态风险和较低生态风险地区呈现扩张趋势;③2000,2010和2020年的全局自相关分析Moran’s I指数均大于0.8,在空间分布上呈显著正相关,绝大多数生态风险单元呈现高—高和低—低分布,少数的生态风险单元在高—高和低—低风险单元周围分布,说明研究区的生态风险比较稳定。④人为干扰度对景观生态风险有很强的解释力,其次为NDVI,各种生态保护活动直接促进了NDVI的提升。[结论]鄂榆地区景观生态风险主要受人类活动的影响,其中以生态保护活动为主的人类活动可以有效降低生态风险。应继续加强对鄂榆地区的生态保护措施,促进生态安全格局的构建。

[Objective]The landscape ecological risk assessment and driving factors in the Ordos-Yulin area was analyzed,in order to provide a scientific basis for the management and restoration of the ecological environment and the construction of the ecological security pattern in this area.[Methods]Based on the land use data of Ordos-Yulin area in 2000,2010 and 2020,ArcGIS 10.2 and Fragstats 4.2 software were used to construct a landscape ecological risk assessment model based on the degree of landscape disturbance and landscape vulnerability.The dynamic analysis of landscape ecological risks was carried out at spatial and temporal scale,and the driving factors of its changes were detected by using geographic detector.[Results]①Grassland,cultivated land and unused land were the main land use types in Ordos-Yulin area,and the intensity and speed of land use was the most active from 2010 to 2020.Grassland was the main type of transfer in and out.②From 2000 to 2010,the areas with medium ecological risk,high ecological risk and high ecological risk showed an expansion trend,while the low ecological risk and low ecological risk showed a contraction trend.From 2010 to 2020,the areas with medium ecological risk,higher ecological risk,and low ecological risk showed a contraction trend,while areas with low ecological risk and lower ecological risk showed an expansion trend;③The global autocorrelation analysis of Moran’s I index in 2000,2010,2020 was greater than 0.8,showing a significant positive correlation in spatial distribution.Most ecological risk units presented high-high and low-low distribution,and a small number of ecological risk units were high-high and low.The distribution around the low-risk unit indicated that the ecological risk in the study area was relatively stable.④According to the analysis of geographic detectors,the degree of human disturbance had a strong explanatory power for landscape ecological risks,followed by NDVI.Various ecological protection activities directly promoted the improvement of NDVI.[Conclusion]Landscape ecological risks in Ordos-Yulin area are mainly affected by human activities,and human activities mainly ecological protection activities,can effectively reduce ecological risks.Accordingly,ecological protection measures should be strengthened to promote ecological security patterns in Ordos-Yulin area.