The RVDM: modelling impacts, evolution and competition processes to determine riparian vegetation dynamics

Abstract

[EN] The riparian vegetation dynamic model (RVDM) is an ecohydrological model aimed to study the vegetation dynamics in riparian areas that represents an upgrade with respect to previous tools in the way of understanding the riparian dynamics. Important novelties are proposed by this tool, including a high temporal resolution (daily time step), a proposal of a new plant classification approach useful for research and management (successional plant functional types), good representation of the key processes that determine the vegetation dynamics in riparian areas (drought and flood impacts, recruitment, growth, succession and competition), an easy implementation and feasible inclusion of river morphodynamics in the model implementation (including different daily elevation and soil maps in the inputs). The model implementation in a Mediterranean semi-arid study site resulted satisfactorily (cell by cell calibration accuracy >= 65% and cell by cell validation accuracy between 40% and 60%), demonstrating the great potential of this approach for future research and management applications. Although 36 parameters are included in the model conceptualization, the global sensitivity analysis demonstrated that only eight types of parameters are actually influent. These parameters are as follows: minimum time since mixed for transition to terrestrial, root depths, transpiration factors, critical shear stress of early stages, minimum biomass required to allow succession, germination minimum capillary water content in the upper soil, effective depth considered for evaporation from bare soil and coverage of pioneers. Riparian vegetation dynamic model will be a useful tool for gaining a better understanding of the riparian plants behaviour under different ecohydrological conditions. Copyright (C) 2015 John Wiley & Sons, Ltd.