Is the Hyporheic Zone Relevant beyond the Scientific Community?

Abstract

Rivers are important ecosystems under continuous anthropogenic stresses. The hyporheic zone is a ubiquitous, reactive interface between the main channel and its surrounding sediments along the river network. We elaborate on the main physical, biological, and biogeochemical drivers and processes within the hyporheic zone that have been studied by multiple scientific disciplines for almost half a century. These previous efforts have shown that the hyporheic zone is a modulator for most metabolic stream processes and serves as a refuge and habitat for a diverse range of aquatic organisms. It also exerts a major control on river water quality by increasing the contact time with reactive environments, which in turn results in retention and transformation of nutrients, trace organic compounds, fine suspended particles, and microplastics, among others. The paper showcases the critical importance of hyporheic zones, both from a scientific and an applied perspective, and their role in ecosystem services to answer the question of the manuscript title. It identifies major research gaps in our understanding of hyporheic processes. In conclusion, we highlight the potential of hyporheic restoration to efficiently manage and reactivate ecosystem functions and services in river corridors.

Groundwater–Surface Water Interactions: Recent Advances and Interdisciplinary Challenges

“…This Special Issue consists of 20 original research papers . The majority of the contributions [3,5,[8][9][10][11][15][16][17][19][20][21][22][23] focus on the interactions between rivers or streams and groundwater. Three studies [6,13,14] investigate the interactions between lakes and groundwater, while two studies [4,18] deal with the exchange between groundwater and oceanic water.…”

“…Exchange fluxes across sediment-water interfaces are frequently studied in detail with a specific focus on the hyporheic zone (i.e., the zone of the stream-groundwater interface where groundwater and stream water mix). Lewandowski et al [22] discuss the valuable ecosystem services provided by the hyporheic zone. Several studies focus on fluxes across the hyporheic zone by using temperature as a tracer.…”

Insight into the influence of local streambed heterogeneity on hyporheic-zone flow characteristics

“…The interaction between surface water and groundwater is an important process in water resources management, influencing aquatic ecosystems (Findlay 1995;Brunke and Gonser 1997;Briggs et al 2015) as well as water quality (Boulton et al 1998;Boano et al 2013;Lewandowski et al 2019). Pressure-driven exchange of water and solutes across the water-streambed interface prolongs the solute residence time in the subsurface and increases the contact time between the sediments and solutes.…”

Mapping Micro-Pollutants and Their Impacts on the Size Structure of Streambed Communities

“…EOCs comprise a vast set of synthetic chemicals, ranging from daily-use pharmaceuticals and personal care products to pesticides and agricultural chemicals [6]. EOC pollution occurs when these chemicals enter natural systems in many different ways, including as a part of wastewater treatment plant release and percolation from agricultural areas in floodplains [11], resulting in a widespread and constant source of pollution (EOC pollution) with the potential to hypothesize that EOC pollution results in detrimental effects to streambed communities, especially for the large-size fractions with lower adaptation capacity to constant exposure to EOCs. Hence, we predict N-M coefficients (intercept and slope) to decrease compared with reference systems.…”