青藏高原人类活动强度时空变化与影响因素

科学评估人类活动强度对于统筹协调青藏高原生态保护与人类活动具有重要意义。基于多期土地利用现状调查数据和陆地表层人类活动强度算法，测算和分析了青藏高原1984年、1997年、2008年和2018年的人类活动强度及其时空变化特征，使用地理探测器定量解析了影响青藏高原人类活动强度空间分异的驱动因素。结果表明：(1)1984—2018年青藏高原人类活动强度总体处于低水平阶段，大致以2008年为节点，前期缓慢下降，后期快速上升，1984年的人类活动强度为1.44%,2018年上升到1.70%;(2)西藏“一江两河”地区(雅鲁藏布江、拉萨河和年楚河)和青海河湟谷地的人类活动强度最高，沿日喀则-拉萨-那曲-玉树-果洛-西宁形成条带状的相对高值分布区，川藏高山峡谷区、藏北-青南高原区和帕米尔山区的人类活动强度最低；(3)人类活动强度空间分异的主要因素为人口密度、道路密度、经济规模、地表起伏度、城镇化水平、第一产业占比和区域发展导向，且各因子间的交互作用解释力显著高于单因子，表现为非线性增强和双因子增强。

Spatio-temporal variation of human activity intensity and its driving factors on the Qinghai-Tibet Plateau

The human activity intensity is a comprehensive indicator that objectively reflects the impact of different human activities on the terrestrial surface and the extent of its effects. The scientific assessment for the human activity intensity has a pivotal role in coordinating regional ecological protection with human activities on the Qinghai-Tibet Plateau. However, the scale and intensity of human activities and its variation patterns on the Qinghai-Tibet Plateau are not yet clear. Therefore, there is an urgent need for quantitative study on the human activity intensity. Based on the multi-period land use survey data and the algorithm of human activity intensity of land surface, this study measured and analyzed the human activity intensity and its spatio-temporal variation characteristics on the Qinghai-Tibet Plateau in 1984, 1997, 2008, and 2018. Subsequently, the driving factors affecting the spatial variation of human activity intensity were detected using the Geographical detector model. This article obtains three conclusions:(1) the overall human activity intensity was generally at a low level on the Qinghai-Tibet Plateau from 1984 to 2018. The human activity intensity has experienced a slight decline from 1.44% in 1984 to 1.37% in 2008, while sharply rose to a high point and peaked to 1.70% in 2018. (2) The regions with the highest intensity of human activity included the Three River Basin in Tibet (Yarlung Zangbo River, Lhasa River, and Nyanchu River) and the Yellow River-Huangshui River Valley region in Qinghai, and a strip-like distribution area of relatively high intensity of human activity was being formed along the Rikaze-Lhasa-Nagqu-Yushu-Guoluo-Xining, while these regions were the lowest in the Alpine-gorge region of Sichuan and Tibet, the Northern Tibetan-Southern Qinghai Plateau, and the Pamir Mountains. (3) The geographical detection results showed that the main factors influencing the spatial differentiation of human activity intensity were population density, road density, economic scales, relief degree of land surface, urbanization rate, the proportion of primary industries, and regional development orientation, and the factors'' explanatory after the interaction was significantly higher than that of single, showing the interaction types of nonlinear-enhance and bi-variable enhance. The conclusions of this study can provide a scientific support and basic reference material for government decisions on the construction of ecological security barrier and spatial governance of territorial space on the Qinghai-Tibet Plateau.