Mapping human footprint changes over Qingzang Plateau

Abstract

Mapping human footprint (HF) is crucial for understanding the cumulative anthropogenic pressures on the environment. However, its effectiveness is often hampered by the absence of fine-scale, high-quality spatio-temporal datasets. Addressing this gap, we present the first annual HF maps for the Qingzang Plateau (QP) from 1990 to 2020, at a 100 m × 100 m resolution, boasting an accuracy exceeding 80 %. Our findings reveal that the QP’s human-induced modifications were relatively low, with a median HF of 3.39 in 2020, significantly lower than the global average of 7.56. The northeast and mid-south regions of the QP emerged as hotspots for anthropogenic impact. Notably, over two-thirds (68.2 %) of the QP registered an HF score below 4, classifying them as largely intact. However, the QP’s average HF score has escalated more swiftly than the global mean (0.0348/yr vs. 0.0186/yr), particularly in the last decade, indicating escalating human pressures. In terms of stability, montane grasslands and shrublands comprised 75.1 % of moderately or highly altered biomes in 2020. In contrast, tropical and subtropical moist broadleaf forests witnessed the most substantial HF increases. Encouragingly, 26.29 % of the QP experienced HF reductions over the past thirty years, highlighting potential conservation opportunities. Conversely, a significant HF increase across 36.59 % of the QP underscores the pressing need to mitigate the adverse effects of intensified human activities. Our HF maps will be conducive to improve understanding the profound impacts wrought by human activities on the QP, and support the conservation planning and resource management needs, as well as decision-making related to restoration objectives.