2000—2015年秦巴山区人类活动强度变化分析

Abstract

Accurate quantification of human activity intensity (HAI) is crucial for understanding land surface changes. The Qinling-Daba Mountains (QDM), spanning six provincial-level regions in China's north-south transitional zone, exhibit complex human-environment interactions due to their ecological significance and long history of anthropogenic influence. This study integrates seven indicators from socio-economic and geographical dimensions, including population density, road density, land transformation degree, distance from roads, distance from settlements, topography and river density, to map HAI distribution across the QDM for 2000 and 2015. HAI changes were analyzed at regional, county, and nature reserve scales. The results showed that: (1) The HAI distribution shows obvious spatial heterogeneity. Some 53.36% of the QDM exhibits moderate-to-higher HAI, with hotspots in the eastern QDM, the Hanshui River Valley and the Western Jialing River Basin as well as the southern flank of the Daba Mountains; while high-altitude mountainous areas (e.g., the Daba Mountains, the central-to-western Qinling Mountains) show lower HAI. (2) The HAI changes of the QDM from 2000 to 2015 show an increasing trend, including 62.31% of the QDM, 61.68% of the counties and 65.45% of nature reserves. (3) The HAI Changes also show a clear spatial differentiation. The southern flank of the Daba Mountains, the eastern Qinling Mountains, the Hanshui River Valley and the Jialing River basin experience an obvious increasing trend; while the northern flank of the Qinling Mountains, the western Qinling Mountains, and the South-to-North Water Diversion Water Resource Breeding Area basically show a decreasing trend, no significant change, or a slight increasing trend. (4) HAI and its changes in the QDM exhibit altitude variations. Low-altitude areas (< 1500 m) display stronger HAI and more significant changes, whereas high-altitude areas (> 2000 m) show low HAI and negligible variation. The HAI datasets enable quantitative assessment of human impacts on vegetation and ecosystem functions, and provide an important basis for identification of ecological fragility for conservation prioritization in this biodiversity hotspot.