2000—2020年汾河流域生态脆弱性时空演变与驱动因素

Spatial-temporal evolution and driving factors of ecological vulnerability in Fenhe River Basin from 2000 to 2020

采用“生态敏感性-生态恢复力-生态压力度”(SRP)评价模型,构建了汾河流域生态脆弱性评价指标体系;利用空间地理数据和主成分分析法,对2000—2020年汾河流域的生态脆弱性、时空分布特征及变化趋势进行了分析;同时借助地理探测器模型,探讨了流域生态脆弱性变化的驱动因素。结果表明:(1)汾河流域生态以中度脆弱为主,在空间上呈现“南高北低”的趋势,在时间上呈现先增加后降低态势,整体生态环境质量逐渐好转。(2)平原丘陵区、低山区生态脆弱性高,中山区次之,高中山区最低。近20 a间,平原丘陵区、低山区、高中山区生态脆弱性降低,中山区生态脆弱性有所增加。(3)影响汾河流域生态脆弱性的驱动因素多样化,在自然、人类活动和景观格局等因素中,土壤有机碳含量、土地利用程度和香农均匀度指数是其生态脆弱性空间分异的主要驱动因素。同时,在政策因素相对稳定的条件下,气候因素对生态脆弱性的影响程度逐步增强。所得结果可为汾河流域合理配置土地资源、保护和修复生态环境、实现高质量发展提供科学依据。

An ecological vulnerability evaluation index system based on the evaluation model of"sensitivity-recovery-pressure"(SRP)is constructed.By using spatial geographical data and spatial principal component analysis(SPAC),the ecological vulnerability status,its spatial-temporal distribution characteristics and change trend of Fenhe River Basin in recent 20 years are analyzed,the driving factors of ecological vulnerability change are also discussed by using geodetector.First,The results show that:(1)The overall ecological vulnerability of Fenhe River Basin was at a moderate level,and the vulnerability level in southern area is higher than that in the northern area.The ecological vulnerability first increased then decreased in the time period,indicating that the quality of ecological environment has changed better from 2000 to 2020.(2)The ecological vulnerability level of these zones,such as the plain,hilly and low mountain,was higher than that of the middle mountain zone,and it was at the lowest level in the high-middle mountain zones.During the past 20 years,the ecological vulnerability level of plain,hilly,low mountain and high-middle mountain zones has decreased,while it has rised on middle-middle mountain zones.(3)The driving factors affecting the ecological vulnerability of Fenhe River Basin are of diversity.Among these factors such as nature environment,human activities and landscape pattern,soil organic carbon contents,land use degree and Shannon's evenness index(SHEI)are the main factors contributing to the spatial differentiation of ecological vulnerability.Under a relatively stable policy of ecological protection,the impact of climate change factors on ecological vulnerability has increased gradually.