A simple index for assessing cumulative human impacts on mountain lakes

Abstract Mountain lakes are highly sensitive ecosystems and effective sentinels of environmental change, yet the exposure and magnitude of the human footprint remain poorly quantified. In this study, we develop a simple and non‐invasive abiotic index to assess cumulative pressures on mountain lakes. The proposed index integrates eight variables grouped into three categories (potential human impacts, accessibility, and recreational exposure) into a single cumulative score, providing a straightforward but informative measure of human pressure on lakes. We employed a dataset comprising 29 lakes from two Iberian protected areas (Sierra de Gredos and Sanabria region) as a case study for assessing the reliability of the index. We observed strong variability among lakes, highlighting the importance of local pressures that are often overlooked by global indicators such as the Human Footprint Index. Our index provides an accessible first‐step diagnostic tool that facilitates the integration of human pressure assessment into site‐specific monitoring and conservation actions.