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Klagenfurt am Wörthersee, Austria

Rivaes R.P.,University of Lisbon | Rodriguez-Gonzalez P.M.,University of Lisbon | Ferreira M.T.,University of Lisbon | Pinheiro A.N.,University of Lisbon | And 4 more authors.
PLoS ONE | Year: 2014

Global circulation models forecasts indicate a future temperature and rainfall pattern modification worldwide. Such phenomena will become particularly evident in Europe where climate modifications could be more severe than the average change at the global level. As such, river flow regimes are expected to change, with resultant impacts on aquatic and riparian ecosystems. Riparian woodlands are among the most endangered ecosystems on earth and provide vital services to interconnected ecosystems and human societies. However, they have not been the object of many studies designed to spatially and temporally quantify how these ecosystems will react to climate change-induced flow regimes. Our goal was to assess the effects of climate-changed flow regimes on the existing riparian vegetation of three different European flow regimes. Cases studies were selected in the light of the most common watershed alimentation modes occurring across European regions, with the objective of appraising expected alterations in the riparian elements of fluvial systems due to climate change. Riparian vegetation modeling was performed using the CASiMiR-vegetation model, which bases its computation on the fluvial disturbance of the riparian patch mosaic. Modeling results show that riparian woodlands may undergo not only at least moderate changes for all flow regimes, but also some dramatic adjustments in specific areas of particular vegetation development stages. There are circumstances in which complete annihilation is feasible. Pluvial flow regimes, like the ones in southern European rivers, are those likely to experience more pronounced changes. Furthermore, regardless of the flow regime, younger and more water-dependent individuals are expected to be the most affected by climate change. Copyright © 2014 Rivaes et al. Source

Garcia-Arias A.,Polytechnic University of Valencia | Frances F.,Polytechnic University of Valencia | Ferreira T.,University of Lisbon | Egger G.,Environmental Consulting Klagenfurt | And 6 more authors.
Ecohydrology | Year: 2013

Riparian ecosystems are required to be preserved to achieve a good ecological status. The Water Framework Directive (2000/60/EC) specifically supports the assessment of new management tools that allow the European Member States to achieve good ecological status of river-related ecosystems. Within several approaches, a dynamic riparian vegetation distributed model (CASiMiR-vegetation), with a time step of 1year, has been selected as a useful first-step tool to achieve the Water Framework Directive requirements. The model has been implemented into three river reaches with different climatic and hydrologic settings, located in three European countries. Common bases were established in the model setup. The model was calibrated independently in the Kleblach reach (Drau River, Austria), the Ribeira reach (Odelouca River, Portugal), and the Terde reach (Mijares River, Spain) with simulation periods of 8, 11 and 41years, respectively. The parameter values and the results were comparable between the different countries. The calibration performance achieved high correctly classified instances (60%). Additionally, weighted kappa values ranged from 0·52 to 0·66 in distinguishing riparian succession phases. The model behaved similarly in the validation, even offering better results in most cases. This work demonstrates the applicability of this model in the simulation of the riparian vegetation dynamic distribution over a wide range of environments. As it performs in a robust manner and with good results in reaches with different hydrological characteristics, the model could be also applied to analyse different hydrological scenarios or to predict changes after restoration measures within a reach. © 2012 John Wiley & Sons, Ltd. Source

Rivaes R.,University of Lisbon | Rodriguez-Gonzalez P.M.,University of Lisbon | Albuquerque A.,University of Lisbon | Pinheiro A.N.,University of Lisbon | And 2 more authors.
Ecological Engineering | Year: 2015

One of the most salient causes of the degradation of freshwater systems is the physical habitat changes attributed to river damming. Environmental flows reduce such degradation but are still generally based on the requirements of aquatic species and disregard other biotic components of the ecosystem, such as riparian vegetation. Nevertheless, when environmental flow methods claim to consider riparian vegetation habitats and propose specific flows, their outcomes are rarely predicted quantitatively prior to their implementation. We used a dynamic floodplain vegetation model to analyze the riparian patch dynamics predicted for different flow regimes in two river stretches and to assess vegetation requirements to ensure long-term ecological maintenance and vitality of riparian structure in rivers with altered flow regimes. Furthermore, we assessed the capability of flushing flows to restore and manage riparian vegetation and the efficiency of environmental flows to satisfy riparian vegetation requirements. We found that vegetation encroachment is mainly prevented by floods with a recurrence interval of at least 2 years but that environmental flow regime planning aimed at complying with riparian vegetation requirements is watershed-specific. Additionally, reservoir flows controlled vegetation encroachment without causing severe geomorphic impacts on downstream river channels and with minor water losses to dam managers. © 2015 Elsevier B.V. Source

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