Hydro-morphological characteristics and recent changes of a nearly pristine river system in Chilean Patagonia: The Exploradores river network

Abstract

Fluvial systems provide multiple life-supporting functions, but their values are affected by a range of anthropogenic disturbances. Hydromorphology is used as a conceptual framework for assessing the status of fluvial systems and design river restoration strategies but is rarely applied to nearly pristine environments. This paper presents one of the first assessments of river characteristics and changes in the Aysen Region, an area in southern Chilean Patagonia. The analysis of multitemporal satellite images allowed to define key patterns related to river morphology of the Exploradores river network. The Exploradores basin experienced only limited and recent human disturbances, and fluvial changes are related almost only to natural climatic or geomorphological processes. The river experienced moderate reduction of active channel width and braiding index over the past 70 years. The basin represents a suitable site to study fluvial processes and dynamics in nearly reference conditions, and changes due to the likely increase of human activities and disturbances in the near future.