Landsystems of the tropical high Peruvian Andes: glaciers, lakes, wetlands and water resources in the Cordillera Vilcanota

The food and water security of 90 million people depends on the Andean Mountain water tower, which is at risk in several regions because climate change is altering water storage in high altitude wetlands (bofedales), lakes, snow and glacier ice. These features play a crucial role in delaying water release, particularly in many semiarid regions with pronounced seasonal drought, sustaining baseflows and water quality. Changing water availability impacts both high Andean pastoralist systems and other productive systems downstream, including bigger cities in the inter-Andean valleys. Here we outline the hydrological and geomorphological relationships between glaciers, lakes and wetlands, and the way in which catchment features such as moraines, talus slopes and sandar interact with catchment hydrology in the tropical Andes of Peru. We present a geomorphological map of catchment features in the Cordillera Vilcanota, Cusco region, Peru, and explore how these features can impact hydrogeological processes. We explore the ways in which well mapped and dated catchment features can give a damming or groundwater/surface water exchange mechanism for bofedal development. Such analysis enables an improved understanding of the timeframe for the formation of wetlands and for them to provide their key ecosystem services of water retention capacity, buffering drought, providing forage for alpaca and herding, and carbon storing and sequestration.