Ecosystem services in drying river networks: a meta-ecosystem conceptual model

Abstract

All river networks are virtually prone to drying, which is dramatically increasing in space and time. This threatens the functions and ecosystem services (ES) rivers provide to societies. Here, we introduce a new conceptual model of the provision of ES in drying river networks (DRN), situating drying as a pivotal element of every river network. Based on a meta-ecosystem perspective, we contend that ES provision is determined in DRN by the exchange of abiotic and biotic flows between terrestrial and aquatic ecosystems in the catchment. Specifically, we highlight three main components of the ecosystem involved: the intensity of abiotic flows, biodiversity patterns, and ecosystem functioning rates. How they vary in space and time due to changes in the hydrological connectivity in catchment-DRN determines the pattern of ES provision along the DRN. Although drying events are the cause of the great diversity of services naturally provided by DRN, we must perceive their anthropogenic increase as a major socio-ecological risk factor.