Modern comprehensive approach to monitor the morphodynamic evolution of restored river corridors
Abstract. River restoration has become a common measure to repair anthropogenically-induced alteration of fluvial ecosystems. The inherent complexity of ecohydrologic systems, leads to limitations in understanding the response of such systems to restoration over time. Up to now a lot of effort has therefore been dedicated worldwide to document the efficiency of restoration actions and to produce new effective guidelines that may help overcoming our deficiencies. At the same time very few attentions focused on illustrating the reasons and the use of certain monitoring and experimental techniques in spite of others, or in relation to the specific ecohydrologic process being investigated. The purpose of this paper is to enrich efforts in this direction by discussing the experimental setup that we designed and installed in order to accomplish some of the research tasks of the multidisciplinary scientific project RECORD (Restored Corridor Dynamics). Therein, we study the morphodynamic evolution of the restored reaches of River Thur near Niederneunforn (Switzerland), also in relation to the role of pioneer vegetation roots in stabilizing the alluvial sediment. In this work we describe and motivate the methodology chosen for monitoring the river morphodynamics, the dynamics of riparian and of in-bed vegetation and their mutual interactions, as well as the need of complementing such observations with experiments and with the hydraulic modeling of the site. We also discuss how the designed installation and the experiments integrate with the needs of other research groups within the project, in particular providing data for a number of investigations ranging from surface water to groundwater, soil moisture and vegetation dynamics.