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Background: The impact of environmental drivers of biodiversity change on the native vegetation of Kazakhstan is so far poorly understood. Aims: To compare historical and contemporary data on the floristic composition of plant communities with Aflatunia ulmifolia against the backdrop of sixty years of climate and land-use change. Methods: In 2021-2022, we revisited a river gorge in the Dzhungarskiy Alatau that had been originally surveyed in 1962. We estimated floristic composition and abundance of species on the Drude scale, and evaluated floristic similarity and abundance change between our dataset and that of 1962. Results: In total, 226 species belonging to 166 genera and 52 families were recorded. The vast majority were native, and only 8 species were exotic. Historical surveys recorded 104 species, and recent surveys, 199 species, the surveys from the two observation periods sharing only 77 species. The Sörensen similarity coefficient was the highest for native shrubs (0.8), and the lowest for native herbaceous plants (0.46). The increase in floristic diversity was largely due to the increase in the number of herbaceous species, mostly perennial forbs. Conclusions: The observed changes could be a result of increased frequency of shallow landslides, grazing exclusion, and growing human presence. [ABSTRACT FROM AUTHOR]

Reports of world-wide decline of pollinators, and of bees in particular, raise increasing concerns about maintenance of pollination interactions. While local factors of bee decline are relatively well known and potential mitigation strategies at the landscape scale have been outlined, the regional and continental-scale threats to bee diversity have only been marginally explored. Here we document large-scale spatial patterns for a representative bee subfamily, the determinants of its species richness, and assess major threats to these pollinators. Using a comprehensive global dataset of Colletinae (genera Colletes, also called 'polyester' or 'cellophane' bees for their underground nests lined with a polyester secretion, and Mourecotelles), a species-rich subfamily whose organismal and physiological ecology is representative of many bees, we measured species richness and endemism on global to continental scales. We explored the relationships between bee species richness and potential environmental stress factors grouped into three categories: contemporary climate, habitat heterogeneity, and anthropogenic pressure. Bees of the subfamily Colletinae demonstrate the reversed latitudinal gradient in species richness and endemism suggested for bees; the highest species richness of Colletinae was found between 30° and 50° latitude in both the northern and southern hemispheres. Centres of endemism largely overlapped with those of species richness. The importance of the Greater Cape Floristic Region, previously identified as a centre of richness and endemism of bees, was confirmed for Colletinae. On the global scale, present-day climate was a significant predictor of species richness as was flowering plant diversity represented by vascular plant species richness and centres of plant diversity. Our main conclusion is that climate change constitutes a potential threat to bee diversity, as does declining diversity of vascular plants. However, a significant overlap between centres of bee richness and plant diversity might increase chances for developing conservation strategies. [ABSTRACT FROM AUTHOR]

Although climatic niche conservatism has been assumed by a large number of studies focused on climatic niche evolution, there are examples of climatic niche diversification and adaptation to changing climates. In this article, we reconstruct a climatic niche of scaly tree ferns (Cyatheaceae) using a rigorous analytical procedure which combines climatic niche modelling with reconstruction of continuous characters given a phylogenetic hypothesis. To estimate the limits to climatic niches of species, we used climate envelope modelling and ordination. Ancestral climatic niches of species were reconstructed by maximum likelihood and least-squares analyses. We observed a trend towards niche conservatism with occasional events of niche transformations in scaly tree ferns. We discuss the implications of our study with respect to the potential and limitations for applications of niche modelling to evolutionary studies. We suggest that future studies of evolution of climatic niches could be considerably improved by employing approaches enabling reconstruction of continuous response to climatic gradients. Further progress may also be achieved by exploring models of character evolution other than the Brownian motion model. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, , 1-19. [ABSTRACT FROM AUTHOR]