title: Inter-species competition-facilitation in stochastic riparian vegetation dynamics.
abstract: Riparian vegetation is a highly dynamic community that lives on river banks and which depends to a great extent on the fluvial hydrology. The stochasticity of the discharge and erosion/deposition processes in fact play a key role in determining the distribution of vegetation along a riparian transect. These abiotic processes interact with biotic competition/facilitation mechanisms, such as plant competition for light, water, and nutrients. In this work, we focus on the dynamics of plants characterized by three components: (1) stochastic forcing due to river discharges, (2) competition for resources, and (3) inter-species facilitation due to the interplay between vegetation and fluid dynamics processes. A minimalist stochastic bio-hydrological model is proposed for the dynamics of the biomass of two vegetation species: one species is assumed dominant and slow-growing, the other is subdominant, but fast-growing. The stochastic model is solved analytically and the probability density function of the plant biomasses is obtained as a function of both the hydrologic and biologic parameters. The impact of the competition/facilitation processes on the distribution of vegetation species along the riparian transect is investigated and remarkable effects are observed. Finally, a good qualitative agreement is found between the model results and field data.
authors.affiliation: Department of Environmental, Land, and Infrastructure Engineering, Politecnico di Torino, Turin, Italy. stefano.tealdi@polito.it
authors.forename: Stefano
authors.initials: S
authors.lastname: Tealdi
authors.forename: Carlo
authors.initials: C
authors.lastname: Camporeale
authors.forename: Luca
authors.initials: L
authors.lastname: Ridolfi
mesh_terms: D018533:Biomass; D003163:Competitive Behavior; D017753:Ecosystem; D057446:Hydrodynamics; D008954:Models, Biological; D063245:Plant Development / Q000502:physiology*; D011157:Population Dynamics; D045483:Rivers; D013045:Species Specificity; D013269:Stochastic Processes