Abstract

Forests without significant human intervention are globally uncommon and rapidly declining, especially in the temperate biome. These ecosystems provide essential habitat for the conservation of biodiversity, mitigation of climate change and regulation of freshwater ecosystems. Efforts towards mapping intact forests globally have advanced via forest patches as the basic conservation unit. We propose an alternative ecosystem-based perspective that takes into consideration the connection between forests and riverine processes, using small watersheds as the unit of analysis. This chapter assesses the distribution of intact forested watersheds in Patagonia, as a more conservative approach to highlight conservation priorities for both terrestrial and aquatic systems. The study consisted of mapping all catchments in Western Patagonia (41–55°S), followed by a two-stage validation based on satellite images and field observations. We summarize the patterns in their distribution based on categories of land use, bioclimatic gradients, forest types and inclusion within protected areas. Large areas of temperate forest watersheds without major human impacts were documented across much western drainage in Patagonia, potentially representing a globally significant biodiversity refuge. However, observations on terrestrial and aquatic biodiversity in these ecosystems is limited, and since nearly half of these systems are located outside of protected areas, there is an urgent need for general baseline observations on the biodiversity of intact watersheds. The chapter concludes with a summary of the challenges and recommendations for the conservation of intact forested watersheds in western Patagonia.