Data/hora: 09/06/2024 14:53:21

Biblioteca(s): | Embrapa Clima Temperado.
Data corrente: | 15/01/2015
Data da última atualização: | 15/01/2015
Autoria: | BLANCO, C. C.; SCHEITER, S.; SOSINSKI, E.; FIDELIS, A.; ANAND, M.; PILLAR, V. P.
Afiliação: | CAROLINA CASAGRANDE BLANCO, UFRGS; SIMON SCHEITER, Biodiversität und Klima Forschungszentrum; ENIO EGON SOSINSKI JUNIOR, CPACT; ALESSANDRA FIDELIS, UNESP; MADHUR ANAND, University of Guelph; VALÉRIO D. PILLAR, UFRGS.
Título: | Feedbacks between vegetation and disturbance processes promotelong-term persistence of forest-grassland mosaics in south Brazil.
Ano de publicação: | 2014
Fonte/Imprenta: | Ecological Modelling, v. 291, p. 224-232, Nov. 2014.
ISSN: | 0304-3800
Idioma: | Inglês
Conteúdo: | Vegetation changes, such as shrub encroachment and forest expansion over grasslands, prairies andsavannas have been related to changes in climatic (mainly rainfall and temperature) and atmosphericconditions (CO2concentration). However, a longstanding question in ecology is how mosaics of forestsand open-canopy ecosystems could persist over millennia in sites where climatic conditions favor forests.Here we tested the influence of interactions between grass-tree competition, environmental hetero-geneity (topography), seed dispersal, initial density and spatial aggregation of vegetation patches anddisturbance behavior (fire) on the long-term coexistence of forests and grasslands in South Brazil. Forthis, we incorporated the adaptive dynamic global vegetation model (aDGVM) into a spatially explicitmodeling approach (2D-aDGVM). Our results showed that recurrent disturbance related to grasses such asfires plays a key role in maintaining the long-term coexistence of forests and grasslands, mainly throughfeedbacks between disturbance frequency and grass biomass. Topographic heterogeneity affected therate of forest expansion by adding spatio-temporal variability in vegetation-fire feedbacks. However, thespatial pattern and connectivity of fire-prone (grasslands) and fire-sensitive (forest) vegetation patcheswere more important to maintain the long-term coexistence of both alternative vegetation states thanthe initial proportion of forest and grasslands patches. The model is the first individual-based DGVM toconsider the combined effects of topography, seed dispersal and fire spread behavior in a spatially explicitapproach.
Palavras-Chave: | Pastagem subtropical; Subtropical grasslands.
Thesagro: | Dispersão de semente; Pastagem; Simulação.
Thesaurus Nal: | seed dispersal.
Categoria do assunto: | --
Registro original: | Embrapa Clima Temperado (CPACT)
Exemplares: | CPACT - (18053-1) - UPC - AP - DD -  -  -  - DIS