Author(s): Valesca Harezlak; Mijke Van Oorschot

Linked Author(s): Valesca Harezlak, Mijke Van Oorschot

Keywords: E-flow; Global data; Stakeholders; Quick scan; Environmental flows

Abstract: Environmental flows (E-flows) are an important concept to explore current and possible future ecological states of fluvial systems. The ecological state of a fluvial system is directly related to the capacity of the system to provide ecosystem services, like water purification, fish production, and floodplain agriculture. The quantification and balancing of these services require the involvement of multiple stakeholders and lies at the heart of the more elaborated E-flow tools. However, those tools are generally time consuming as large amounts of data are required. As publicly accessible global data becomes increasingly available, as well as methods to extract and convert this data into ecologically relevant parameters, a Rapid Environmental-flow Assessment and Communication Tool (REACT) is proposed to aid data availability in E-flow studies. REACT aims at combining global data and tools with ecological knowledge. Global data holds information on river hydro-morphodynamics, water quality and ecology. Due to the relatively coarse nature of the data the ecological indicators in REACT are based on trait strategies rather than specific species. The included case study of the Tenryū river in Japan showed that discharge and water levels deduced from global data are comparable to those simulated by a calibrated 2D model. The trait strategy approach showed dominant fish guilds that are known to inhabit the Tenryū river in large numbers. Although some deduced E-flow parameters from global data show room for improvement and some parameters are still to be tested, REACT seems to be of added value to the existing E-Flow tools.

DOI: https://doi.org/10.3850/IAHR-39WC252171192022859

Year: 2022