River restoration: morphological, hydrological, biogeochemical and ecological changes and challenges

Abstract

River restoration is essential as a means to enhance river dynamics, environmental heterogeneity and biodiversity. The underlying processes governing the dynamic changes need to be understood thoroughly to ensure that restoration projects meet their goals. In particular, we need to understand quantitatively how hydromorphological variability relates to ecosystem functioning and services, biodiversity and (ground)water quality in restored river corridors. Here, we provide a short overview on the literature and present a study of a restored river corridor in Switzerland combining physical, chemical, and biological observations with modeling. The results show complex spatial patterns of bank infiltration, habitat-type, biotic communities and biogeochemical processes. In particular, we found an increase in taxonomic and functional diversity for earthworms, testate amoebae and bacteria in the restored part of the river. This complexity is driven by river hydrology and morphodynamics, which are in turn actively coupled to riparian vegetation processes. Given this complexity and the multiple constraints on the uses and management of floodplains, a multi-disciplinary approach is needed to monitor the success of restoration measures and to make recommendations for future restoration projects

Evidence of increase in woody vegetation in a river corridor, Northwest England, 1984–2007

“…River corridors are prime locations for maintenance of such connected habitats, and riverbanks can be refuges (Smart et al, 2005). The presence of riparian vegetation delivers many benefits, and much recent research has also been stimulated by a need for greater understanding of dynamics in order to implement protection and restoration (Bennett, Wu, Alonso, & Wang, 2008;Richter & Richter, 2000;Sandercock & Hooke, 2010;Schirmer et al, 2014;Tabacchi, Steiger, Corenblit, Monaghan, & Planty-Tabacchi, 2009). …”

A novel method to evaluate the effect of a stream restoration on the spatial pattern of hydraulic connection of stream and groundwater

“…The main reasons for that are the valuation of river ecosystems as place for species conservation and habitat diversity, recreational and aesthetic purposes, flood protection, enhancing the potential of contaminant deposition and nutrient degradation Kondolf et al, 2007;Hester and Gooseff, 2010;Pander and Geist, 2013;Schirmer et al, 2013). This is also reflected in a growing body of legislative directives (Pander and Geist, 2013;Schirmer et al, 2013), e.g.…”

Research on the Sustainable Development of the Bistrita Ardeleana River in Order to Stop the Erosion of the Riverbanks and the Thalweg

“…In the last two decades, the revitalization of anthropogenic rivers has been established in Europe as a measure to achieve the good ecological status of water bodies, as required by the EU Water Framework Directive (European Commission, 2000), while protecting the objectives downstream of floods. The implementation of the Water Framework Directive in ensuring sustainable water management has been implemented taking into account river basins [1,25,26]. These legislative efforts and necessary actions conclusively aim at increasing the heterogeneity of ecosystems.…”