Anthropogenic modifications and river ecosystem services: A landscape perspective.

Abstract

The process of development has led to the modification of river landscapes. This has created imbalances between ecological, economic, and socio-cultural uses of ecosystem services (ESs), threatening the biotic and social integrity of rivers. Anthropogenic modifications influence river landscapes on multiple scales, which impact river-flow regimes and thus the production of river ESs. Despite progress in developing approaches for the valuation ecosystem goods and services, the ecosystem service research fails to acknowledge the biophysical structure of river landscape where ecosystem services are generated. Therefore, the purpose of this review is to synthesize the literature to develop the understanding of the biocomplexity of river landscapes and its importance in ecosystem service research. The review is limited to anthropogenic modifications from catchment to reach scale which includes inter-basin water transfer, change in land-use pattern, sub-surface modifications, groundwater abstractions, stream channelization, dams, and sand mining. Using 86 studies, the paper demonstrates that river ESs largely depend on the effective functioning of biophysical processes, which are linked with the geomorphological, ecological, and hydrological characteristics of river landscapes. Further, the ESs are linked with the economic, ecological, and socio-cultural aspect. The papers show that almost all anthropogenic modifications have positive impact on economic value of ESs. The ecological and socio-cultural values are negatively impacted by anthropogenic modifications such as dams, inter-basin water transfer, change in land-use pattern, and sand mining. The socio-cultural impact of ground-water abstraction and sub-surface modifications are not found in the literature examined here. Further, the ecological and socio-cultural aspects of ecosystem services from stakeholders’ perspective are discussed. We advocate for linking ecosystem service assessment with landscape signatures considering the socio-ecological interactions