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Vegetation Scientists (vegetation + scientists)
Selected AbstractsTwentieth year of the Journal of Vegetation Science: the journal for all vegetation scientistsJOURNAL OF VEGETATION SCIENCE, Issue 1 2009J. Bastow Wilson [source] Impacts of global change on plant diversity and vice versa: Old and new challenges for vegetation scientistsJOURNAL OF VEGETATION SCIENCE, Issue 6 2005Frank Berendse Abstract. The desire to stop the current dramatic loss of biodiversity has been a major stimulus for many vegetation ecologists to unravel the mechanisms responsible for the coexistence of species. After the Rio Janeiro Convention many ecologists were convinced that nature conservation would gain strong societal support if they could prove that the loss of species would have important negative effects on the ecosystem functions that are relevant to society. I conclude that in order to understand such possible effects, it is necessary to analyse the effects of individual species on those ecosystem processes that we consider to be relevant in the context of specific questions. The great challenge for the near future is to scale the effects of plant species on their local environment up to the level of the whole planet, so that we learn about possible feedbacks that might regulate or destabilize those characteristics of the globe that are essential to our society. [source] Effects of sampling teams and estimation methods on the assessment of plant coverJOURNAL OF VEGETATION SCIENCE, Issue 6 2003Suzanne M. Kercher Abstract. We evaluated variability in cover estimation data obtained by (1) two sampling teams who double sampled plots and (2) one team that used two methods (line intercepts and visual estimation of cover classes) to characterize vegetation of herbaceous wetlands. Species richness and cover estimates were similar among teams and among methods, but one sampling team scored cover higher than the other. The line intercept technique yielded higher cover estimates but lower species richness estimates than the cover class method. Cluster analyses of plots revealed that 36% and 11% of plots sampled consecutively by two teams or using two methods, respectively, were similar enough in species composition and abundance to be paired together in the resulting clustering tree. Simplifying cover estimate data to presence/absence increased the similarity among both teams and methods at the plot scale. Teams were very similar in their overall characterization of sites when cover estimation data were used, as assessed by cluster analysis, but methods agreed best on their overall characterization of sites when only presence/absence data were considered. Differences in abundance estimates as well as pseudoturnover contribute to variability. For double sampled plots, pseudoturnover was 19.1%, but 57.7% of pseudo-turnover cases involved taxa with , 0.5% cover while only 3.4% involved taxa with > 8% cover. We suggest that vegetation scientists incorporate quality control, calibrate observers and publish their results. [source] Applied Vegetation Science in 2010: new opportunities for the vegetation scientistsAPPLIED VEGETATION SCIENCE, Issue 1 2010Alessandro Chiarucci First page of article [source] | ||||||||||