CONICET | Buscador de Institutos y Recursos Humanos

The classic ecological paradigm for deserts, that all processes are controlled by water availability, has limited our imagination for exploring other controls on carbon and nutrient cycling in aridland ecosystems. This review of recent studies identifies alternative mechanisms that challenge the idea that all soil processes in aridlands are proximately water-limited, and highlights the significance of photodegradation of aboveground litter and the overriding importance of spatial heterogeneity as a modulator of biotic responses to water availability. As aridlands currently occupy more than 30% of the terrestrial land surface and are expanding, it is critical to incorporate these previously unappreciated mechanisms in our understanding of aridland biogeochemistry in order to mitigate effects of desertification and global change.