9 research outputs found

    BIODIVERSITY AND CONSERVATION

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    We asked: (i) Which environmental factors determine the level of alpha-diversity at several scales and beta-diversity in steppic grasslands? (ii) How do the effects of environmental factors on alpha- and beta-diversity vary between the different taxonomic groups (vascular plants, bryophytes, lichens)? We sampled nested-plot series ranging from 0.0001 to 100 m(2) and additional 10-m(2) plots, covering different vegetation types and management regimes in steppes and semi-natural dry grasslands of Central Podolia (Ukraine). We recorded all terricolous taxa and used topographic, soil, land-use and climatic variables as predictors. Richness-environment relationships at different scales and across taxonomic groups were assessed with multimodel inference. We also fitted power-law species-area relationships, using the exponent (z value) as a measure of beta-diversity. In general, the richness values in the study region were intermediate compared to those known from similar grasslands throughout the Palaearctic, but for 1 cm(2) we found seven species of vascular plants, a new world record. Heat index was the most important factor for vascular plants and bryophytes (negative relation), while lichen diversity depended mainly on stone and rock cover (positive). The explanatory power of climate-related variables increased with increasing grain size, while anthropogenic burning was the most important factor for richness patterns at the finest grain sizes (positive effect). The z values showed more variation at the finest grain sizes, but no significant differences in their mean between scales. The results highlight the importance of integrating scale into ecological analyses and nature conservation assessments in order to understand and manage biological diversity in steppe ecosystems

    TUEXENIA

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    We present the data of the 2nd research expedition of the European Dry Grassland Group (EDGG), which was conducted in 2010 in Central Podolia, Ukraine. The aim was to collect plot data to compare Ukrainian dry grasslands with those of other parts of Europe in terms of syntaxonomy and biodiversity. We sampled 21 nested-plot series (0.0001-100 m(2)) and 184 normal plots (10 m(2)) covering the full variety of dry grassland types occurring in the study region. For all plots, we recorded species composition of terrestrial vascular plants, bryophytes and lichens, while for the 226 10-m(2) plots we estimated and measured percentage cover of all species, structural, topographic, soil and landuse parameters. The 10-m(2) plots were used for phytosociological classification based on iteratively refined TWINSPAN classification as well as for DCA ordination. Differences between the derived vegetation types with respect to environmental conditions and species richness were assessed with ANOVAs. We assigned our plots to nine association-level units but refrained from placing them into formal associations with two exceptions. In the study area, dry grasslands of the Festuco-Brometea were far more common than those of the Koelerio-Cotynephoretea. Among the Festuco-Brometea, xeric Festucetalia valesiacae grasslands were more frequent and represented by the Festucion valesiacae (2 associations, including the Allio taurici-Dichanthietum ischaemi ass. nova) and the Stipion lessingianae (1) compared to the Brachypodietalia pinnati with the Agrostio vinealis-Avenulion schellianae (3). The Koelerio-Corynephoretea were represented by three associations, each from a different order and alliance: basiphilous outcrops (Alysso alyssoidis-Sedetalia: Alysso alyssoidis-Sedion?), acidophilous outcrops (Sedo-Scleranthetalia: Veronico dillenii-Sedion albi?) and mesoxeric sandy grasslands (Trifolio arvensis-Festucetalia ovinae: Agrostion vinealis). We discuss the issue of the mesoxeric order Galietalia veri placed within the Molinio-Arrhenatheretea by Ukrainian authors and conclude that the content of that order would probably be better placed in the mesoxeric orders of the Koelerio-Cotynephoretea and Festuco-Brometea. Other syntaxonomic questions could not be solved with our geographically limited dataset and await a supraregional analysis, e.g. whether the Ukrainian outcrop communities should be assigned to the same alliances as known from Central Europe or rather represent new vicariant units. The analysis of the biodiversity patterns showed that at a grain size of 10 m(2), Podolian Koelerio-Corynephoretea communities were overall richer than Festuco-Brometea communities (46.4 vs. 40.6 species). This difference was due to the Koelerio-Corynephoretea containing twice as many bryophytes and nine times more lichens, while vascular plant species richness did not differ significantly between classes. The orders within the classes showed no real differences in species richness. The richness patterns observed in Podolia were almost the opposite of those usually found in dry grasslands, where Brachypodietalia pinnati are richer than Festucetalia valesiacae, and these richer than stands of the Koelerio-Corynpehoretea - and we do not have a good explanation for these idiosyncrasies. In conclusion, Podolian dry grasslands behave quite unexpectedly regarding biodiversity, and their syntaxonomy is still poorly understood. These knowledge gaps can only be addressed with supra-national analyses based on comprehensive datasets

    Energy security through the lens of renewable energy sources and resource efficiency

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    This chapter provides an overview of the genesis and transformation of the notion of energy security over time, outlines the prevailing shifts in patterns and concepts of energy security in the twenty-first century, and discusses attempts to conceptualise energy security. It also offers a novel conceptualisation of energy security and compares available approaches with the proposed concept. The chapter defines energy security as sustainable use of renewable energy sources (RES), which means the purposeful and ever-increasing utilisation of renewable sources for the production of power, and a corresponding decrease in reliance on non-renewable sources, complemented by resource efficiency programmes. The chapter emphasises the need for effective governance, focusing on ensuring long-term economic, social and environmental sustainability

    The Palaearctic steppe biome: a new synthesis

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