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, P., Capece , A. & Jespersen , L. (2006): Taxonomic and ecological diversity of food and beverage yeasts.-in: Querol , A. & Fleet , G.H. (Eds) The yeast handbook: Yeasts in food and beverages . Springer-Verlag, Berlin, Germany, pp. 13

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Introduction Classroom diversity means differences in nationality, gender, religion, social status, parents' income, capabilities etc. ( Strasser, 2016 , p. 28 ff.; Walgenbach, 2014 , p.12). For teachers and other educational staff, it is important

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327 372 Deyab, M. A., Nemat Allah, M. M. and El-Adl, M. F. (2002): Phytoplankton diversity in some ponds at new Damietta-Egypt. - Egyp. J. Phyco. 3 : 1

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The genetic diversity of 116 spring bread wheat cultivars released in Kazakhstan from 1929-2004 was studied by means of a genealogical analysis. The tendency of genetic diversity to change over time was traced by analysing a series of n ´ m matrices, where n is the number of released cultivars and m is the number of landrace ancestors. The pool of landrace ancestors of spring wheat cultivars in 1929-2004 contained a total of 114 landraces and old varieties, including 19 from Kazakhstan and Central Asia and 23 from neighbouring regions of Russia. The original ancestors differ significantly in frequency of presence and hence in their importance in the genepool of spring wheats cultivated in Kazakhstan. Significant differences in the contributions of dominant ancestors to cultivars for various regions have been revealed, showing that those ancestors were specifically adapted to different growing conditions. During the past 75 years, genetic diversity has increased due to the wide use of foreign materials in breeding programmes. A more detailed study has shown that during the period analysed, 15 landraces from Kazakhstan and neighbouring regions of Central Asia and Russia (35% of local germplasm) were lost from the pedigrees. The cluster structure of modern cultivars included in the Kazakhstan Official List (2002) was established. By analysing coefficients of parentage, significant differences in the genetic diversity of cultivars from various growing regions were revealed.

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The diversity of the brachiopods in the Northern Caucasus significantly fluctuated throughout the Paleozoic-Mesozoic. Weak diversifications occurred in the Middle Cambrian, Late Silurian - Early Devonian, and Late Devonian - Early Carboniferous. Since the Late Permian brachiopod assemblages became quite diverse. The maximum number of species was reached in the Rhaetian. The Permian/ Triassic mass extinction and enigmatic Ladinian crisis, on the other hand, led to regional brachiopod demises. In the Jurassic - Early Cretaceous interval the diversity of brachiopods generally decreased. The strongest drops of species numbers occurred in the Toarcian and Berriasian following the Pliensbachian-Toarcian and end-Jurassic global mass extinctions, and in the Kimmeridgian due to the regional salinity crisis. It is evident that some of the regional brachiopod diversifications coincided with the development of rimmed shelves.

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Abstract

A key structural component in peat bog formation is Sphagnum spp., which determines very specific associated environmental conditions. The aim of this study was to characterise some of the key factors affecting the diversity, species richness and abundance of sphagnum inhabiting ground beetles and to examine the maintenance of stable populations of cold adapted specialised peat bog species. A total of 52 carabid species were recorded by pitfall traps along six main habitats, such as the lagg zone, pine bog, hollows, hummock open bog and dome. The results are characterised by a low diversity, which vary significantly among habitat types, and include a high abundance of a few carabid species. Among the variables influencing carabid species richness and abundance were plant cover, pH and the conductivity of the Sphagnum mat water. Vascular plant cover was a key factor shaping carabid beetle assemblages in the slope and the dome, while electric conductivity affected carabid beetle assemblage in the lagg. Whereas, the water level was the most important factor for the hollows. At the same time, peat bog specialists showed low sensitivity to the gradient of the analysed variables. Most of the specialised species are protected boreal beetles in the temperate zone of Europe, and therefore Belarusian peat bogs are a significant repository of cold adapted specialised bog species and potentially represent a significant refugia for these species in the context of global warming.

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Scientometrics
Authors: Stephen Carley and Alan L. Porter

to measure the “integration” of academic disciplines. These analyses seek to assess how an author or publication weaves previously disparate knowledge into one fabric. The “Integration score” calculates the diversity of a set of references based upon

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Berger, W.H. and F.L. Parker. 1970. Diversity of planctonic Foraminifera in deep sea sediments. Science 168:1345-1347. Diversity of planctonic Foraminifera in deep sea sediments Science

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Alatalo, R. and R. Alatalo. 1977. Components of diversity: Multivariate analysis with interaction. Ecology 58: 900-906. Components of diversity: Multivariate analysis with interaction

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1227 1239 Baselga, A. 2010. Partitioning the turnover and nestedness components of beta diversity. Global Ecol. Biogeogr. 19: 134

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