0000000001324782
AUTHOR
Vidar Grøtan
showing 2 related works from this author
Effects of density, species interactions, and environmental stochasticity on the dynamics of British bird communities
2022
Our knowledge of the factors affecting species abundances is mainly based on time-series analyses of a few well-studied species at single or few localities, but we know little about whether results from such analyses can be extrapolated to the community level. We apply a joint species distribution model to long-term time-series data on British bird communities to examine the relative contribution of intra- and interspecific density dependence at different spatial scales, as well as the influence of environmental stochasticity, to spatiotemporal interspecific variation in abundance. Intraspecific density dependence has the major structuring effect on these bird communities. In addition, envi…
Mutualistic interactions along a fragmentation gradient
2018
Forest cover loss and fragmentation due to land use changes are one of the principal causes of global biodiversity loss. Indirectly, forest fragmentation can reduce biodiversity and ecosystem functioning by disrupting species interaction networks. Interaction networks, such as seed dispersal networks, are fundamental in maintaining ecosystem services. In tropical forests, frugivorous animals are the most important seed dispersers and thus the main agents of forest regeneration. In general, large tree species produce large seeds that are dispersed by large frugivores. Therefore, in absence of large frugivores, the average size in the tree community is hypothesized to eventually decrease whic…