Spatial Patterns of Glacier Meltwater and Mountain Wetland Connectivity in the Peruvian Andes

Dingyu Xuan , Rike Becker, Miguel Christian Vargas Valverde, Bethan J Davies, Jeremy C. Ely, Owen King, Nilton Montoya, Christian Onof, Anthony C. Ross, Wouter Buytaert

High-altitude wetlands are critical ecosystems that store water, regulate downstream flows, and sustain biodiversity. Their persistence is tightly linked to continuous water inputs from precipitation, groundwater, snow and glacier melt, making them highly vulnerable to climate-driven shifts in mountain hydrology. Rapid glacier retreat, altered precipitation regimes, and rising temperatures are transforming water availability across mountain regions worldwide, but their consequences for wetland stability remain poorly understood. Here, using high-resolution satellite-based mapping (2019–2025) and statistical analyses, we investigate the spatiotemporal dynamics and hydroclimatic drivers of high-altitude wetlands at two tropical Andean study sites in Peru: Cordillera Vilcanota and La Raya. We demonstrate that precipitation is the primary driver of wetland seasonality, explaining up to 25% of the observed variability. This influence weakens in areas close to glaciers, where wetlands exhibit reduced seasonal fluctuations, suggesting a local dampening effect of glacial runoff on wetland wetting–drying cycles. Our spatially explicit analysis demonstrates that this dampening effect attenuates rapidly with distance and is no longer detectable beyond approx. 12 km from glaciers, indicating that the hydrological influence of glacier melt is highly localized and that most high-mountain wetlands are effectively decoupled from glacier-melt processes. The study highlights the critical role of glacier-wetland hydrological connectivity in the context of hydrological changes in mountain regions.