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An extensive data set of the occurrence of 55 cladoceran species in 432 Alpine lakes was used to document patterns of species richness, assemblage composition and distribution across the Alpine ecoregion in Italy, determining the spatial and macroecological parameters explaining the observed patterns. Moreover, the influence of dispersal, environmental filtering and life cycle strategies in shaping cladoceran alpha and beta-diversity patterns was examined. Only three species where widely distributed in the Alpine lakes, with more than 80 % of the species present in less than 10 % of the lakes. Alpha-diversity ranged from 1 to 13 species, while beta-diversity was almost exclusively due to spatial turnover. Our data suggest that the excess of rarity in these environments was better explained by post-glacial random recolonization patterns, high dispersal ability, peculiar life strategies including the production of diapausing eggs, and compliance of cladocerans to the monopolization hypothesis. Spatial determinants (studied using Moran’s Eigenvector Maps) were important for large scale species distribution patterns, suggesting that dispersal was not a limiting factor, although altitudinal heterogeneity shaped beta-diversity patterns. The altitudinal gradient (together with the associated macroclimatic factors) was the second main determinant of species distribution, followed by the geological setting of the basins. Local factors played only a minor role in explaining cladoceran distribution patterns at the ecoregional scale., SCOPUS: ar.j, info:eu-repo/semantics/published

Background and AimsThe botanic gardens of the world are now unmatched ex situ collections of plant biodiversity. They mirror two biogeographical patterns (positive diversity-area and diversity-age relationships) but differ from nature with a positive latitudinal gradient in their richness. Whether these relationships can be explained by socio-economic factors is unknown. MethodsSpecies and taxa richness of a comprehensive sample of botanic gardens were analysed as a function of key ecological and socio-economic factors using (a) multivariate models controlling for spatial autocorrelation and (b) structural equation modelling. Key ResultsThe number of plant species in botanic gardens increases with town human population size and country Gross Domestic Product (GDP) per person. The country flora richness is not related to the species richness of botanic gardens. Botanic gardens in more populous towns tend to have a larger area and can thus host richer living collections. Botanic gardens in richer countries have more species, and this explains the positive latitudinal gradient in botanic gardens' species richness. ConclusionsSocio- economic factors contribute to shaping patterns in the species richness of the living collections of the world's botanic gardens. © The Author 2010. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals. permissionsoxfordjournals.org., SCOPUS: ar.j, info:eu-repo/semantics/published

Background and AimsThe botanic gardens of the world are now unmatched ex situ collections of plant biodiversity. They mirror two biogeographical patterns (positive diversity-area and diversity-age relationships) but differ from nature with a positive latitudinal gradient in their richness. Whether these relationships can be explained by socio-economic factors is unknown. MethodsSpecies and taxa richness of a comprehensive sample of botanic gardens were analysed as a function of key ecological and socio-economic factors using (a) multivariate models controlling for spatial autocorrelation and (b) structural equation modelling. Key ResultsThe number of plant species in botanic gardens increases with town human population size and country Gross Domestic Product (GDP) per person. The country flora richness is not related to the species richness of botanic gardens. Botanic gardens in more populous towns tend to have a larger area and can thus host richer living collections. Botanic gardens in richer countries have more species, and this explains the positive latitudinal gradient in botanic gardens' species richness. ConclusionsSocio- economic factors contribute to shaping patterns in the species richness of the living collections of the world's botanic gardens. © The Author 2010. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals. permissionsoxfordjournals.org., SCOPUS: ar.j, info:eu-repo/semantics/published

Non-indigenous marine species (NIMS) have only recently caught general interest in Denmark, and baseline studies are needed to identify what species are of particular importance in order to prioritize management and research efforts. We used large data sets compiled in monitoring databases to quantify annual nation-wide changes in abundance of non-indigenous soft-bottom invertebrates (from grab samples) and hard-bottom macroalgae (from diver based percent cover values) in Denmark. Based on criteria of being either abundant (constituting >1% of the entire Danish assemblages) or increasing in abundance, NIMS of particular interest were found to be Mya arenaria and Bonemaissonia hamifera (abundant), Crepidula fornicata, Ensis americanus, Neanthes succinea (a cryptogenic species), Marenzelleria spp. (increasing), and Sargassum muticum (abundant and increasing). In addition, new and/or warm-water eurohaline NIMS such as Gracilaria vermiculophylla and Crassostrea gigas, should be given attention as these species are expected to increase in the future. Finally, species not included in existing monitoring programs (hard-bottom estuarine invertebrates, fish, parasites, highly mobile species) should also be targeted in future sampling programs.

Non-indigenous marine species (NIMS) have only recently caught general interest in Denmark, and baseline studies are needed to identify what species are of particular importance in order to prioritize management and research efforts. We used large data sets compiled in monitoring databases to quantify annual nation-wide changes in abundance of non-indigenous soft-bottom invertebrates (from grab samples) and hard-bottom macroalgae (from diver based percent cover values) in Denmark. Based on criteria of being either abundant (constituting >1% of the entire Danish assemblages) or increasing in abundance, NIMS of particular interest were found to be Mya arenaria and Bonemaissonia hamifera (abundant), Crepidula fornicata, Ensis americanus, Neanthes succinea (a cryptogenic species), Marenzelleria spp. (increasing), and Sargassum muticum (abundant and increasing). In addition, new and/or warm-water eurohaline NIMS such as Gracilaria vermiculophylla and Crassostrea gigas, should be given attention as these species are expected to increase in the future. Finally, species not included in existing monitoring programs (hard-bottom estuarine invertebrates, fish, parasites, highly mobile species) should also be targeted in future sampling programs.