Implementing a dynamic riparian vegetation model in three European river systems

Abstract

Riparian ecosystems are required to be preserved to achieve the good ecological status. The Water Framework Directive (WFD 2000/60/EC) specifically supports the assessment of new management tools that allow the European Member States to achieve the good ecological status of the river related ecosystems. Within several approaches, a dynamic riparian vegetation distributed model (CASiMiR-vegetation), with a time step of one year, has been selected as a useful first-step tool to achieve the WFD 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 set-up. 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 41 years respectively. The parameters values and the results were comparable between the different countries. The calibration performance achieved high correctly classified instances (CCI ≈ 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 This is a pre-copyedited, author-produced PDF version following peer review of the article: García-Arias A., Francés F., Ferreira T., Egger G., Martínez-Capel F., Garófano-Gómez V., Andrés-Doménech I., Politti E., Rivaes R., Rodríguez-González P.M. (2013). Implementing a dynamic riparian vegetation model in three European river systems. Ecohydrology, 6(4):635-651. doi: 10.1002/eco.1331, which has been published in definitive publisher-authenticated form at http://onlinelibrary.wiley.com

Using CASIMIR-VEGETATION Model in the context of modeling riparian woods and fish species to support a holistic approach for environmental flows to be used on river management and conservation

“…The model was properly calibrated and validated in Mediterranean rivers with substantial accuracy. These results, together with similar ones achieved in study sites located all over the world (Egger et al 2009b;Benjankar et al 2011;Egger et al 2012;García-Arias et al 2013), show the robustness of the model and its capacity to correctly reproduce the riparian vegetation dynamics facing the main aspects of river disturbance in the more diverse cases.…”

“…Climate change scenarios project for the year 2100 a change in the Mediterranean climate towards more intense winter floods, concentrated in a smaller period, while summer droughts will be more prolonged and harsh (Santos et al 2002;Santos and Miranda 2006). Accordingly to CASiMiRvegetation model, these conditions will determine the removal of the pioneer and young succession phases in the inner areas of the river and the aging of the remaining ones (Rivaes et al 2013). Due to the advantage of the model working fashion (using flow response guilds), results were comparable to similar European studies, revealing the increased distress that Mediterranean riparian ecosystems will endure in the future when compared with temperate or mountain flow regimes (Politti et al 2014;Rivaes et al 2014).…”

“…The climate change scenarios were attained from the forecasts of global and regional circulation models applied to Portugal country limits (Santos et al 2002;Santos and Miranda 2006). The CASiMiRvegetation model was used to model the corresponding modified flow regimes in the ODLC study site and thus determine the expected riparian landscape changes occurring in the Mediterranean climate driven by different climate change scenarios (see Rivaes et al 2013 for a better understanding).…”

“…The intensification of heavy rain events during winter along with longer and harsher droughts during summer will determine the increased retrogression of riparian vegetation near the river channel due to the enlarged morphodynamic disturbance of floods and the inability to reestablish in those areas again due to the reduced soil water moisture. These conditions determine the outwards expansion of non-woody sparsely vegetated areas and the inwards expansion of mature succession patches, while promoting the disappearance of intermediate pioneer and young succession stages of riparian woodlands (Rivaes et al 2013) (Figure 3). These results are particular of the Mediterranean climate, as in temperate rivers the climate change will not cause such drastic effects on riparian vegetation (Politti et al 2014;Rivaes et al 2014).…”

“…This tool recreates the physical processes influencing the survival and recruitment of riparian vegetation, resulting in a temporal and spatial illustration of the riparian vegetation patches. The dynamic vegetation model CASiMiR-vegetation has proved to be a valuable instrument to perform this task (see Benjankar 2009;Benjankar et al 2009;Egger et al 2009a;Egger et al 2009b;Benjankar et al 2011;García-Arias et al 2011;Rivaes et al 2011;Benjankar et al 2012;Egger et al 2012;Egger et al 2013;García-Arias et al 2013;Rivaes et al 2013;Politti et al 2014;Rivaes et al 2014;Rivaes et al 2015b). The tool is a dynamic rule-based spatially distributed model that simulates vegetation dynamics based on the relationship between ecologically relevant flow regime components (Poff et al 1997) and riparian vegetation metrics that reflect the vegetation's responses to flow regime change, such as age distribution, composition and cover (Merritt et al 2010).…”