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Species Composition of the Family Arrhopalitidae (Collembola, Symphypleona)

Species Composition of the Family Arrhopalitidae (Collembola, Symphypleona)

Species composition of a recently revised family Arrhopalitidae is provided. 31 species are listed within the genus Arrhopalites Börner, 1906 and 83 species and subspecies within the genus Pygmarrhopalites Vargovitsh, 2009. 79 species are transferred from the genus Arrhopalites to Pygmarrhopalites; now combinations are listed.

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Species Composition and Biotopical Distribution of Blackflies (Diptera, Simuliidae) on the South-Western Macroslope of the Ukrainian Carpathians

Abstract

The blackflies on the south-western macroslope of the Ukrainian Carpathians are represented by 45 species. Forty of them are registered in the rivers (Simpson’s diversity index (Іs) equals to 0.019), and 29 species in the streams (Іs — 0.090). Twenty-four simuliid species are common for both types of water ways (Czekanowski/Sørensen similarity index (І) is 0.4). Only 16 species develop in the rivers, and 5 types of blackflies live only in the streams. Mass development of the following species in hydrobiocoenoses on the south-western macroslope of the Ukrainian Carpathians: Simulium trifasciatum and S. ornatum. Species such as S. ornatum, S. reptans and S. trifasciatum are widespread here. Simuliid faunas of main regional altitudinal plant groups differed in composition and quantitative correlation of species. Simulium argyreatum, S. intermedium, S. ornatum, S. trifasciatum and S. variegatum were eurytopic. The reachest species composition (29) was recorded in Rakhiv subdistrict in the district of spruce-fir-beech, spruce-beech-fir and spruce-beech Transcarpathian forests, and the poorest composition (15) is in the beech forests of southern megaslope of the Polonynian Beskyd, subdivision of beech Carpathian forests.

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Tree Species Composition and Forest Stratification along the Gradients in the Dry Deciduous Forests of Godavari Valley, Telangana, India

Abstract

It is important to understand the tree species composition, abundance, species diversity and stratification in tropical dry deciduous forests that are under threat. A quadrat study was attempted in the dry deciduous forests along the ecological gradients in the Godavari Valley of northern Telangana, India. The study records the presence of 110 flowering plant taxa belonging to 82 genera and 37 families in 120 sampled plots, and there was enumeration of 15,192 individuals of ≥10 cm girth at breast height. Tectona grandis (teak) is the principal forest cover component in the region, which often formed pure stands in Adilabad and, to some extent, in Nizamabad districts. Further down to the Warangal district, teak was gradually replaced by Terminalia alata. Twenty tree species were found dominant at one place to the other, and the top 10 dominant taxa have shared nearly 41% of the total density of the forest cover. The tree relative density ranged from 0.007% to 20.84%. The values of Importance Value Index were between 0.245 (12 spp. including some exotics) and 32.6 (teak). These baseline data help to know the change detection along the gradients in the tropical forest ecosystem of a major river valley in the region and the drivers of change

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Estimation of standing wood volume and species composition in managed nemoral multi-layer mixed forests by using nearest neighbour classifier, multispectral satellite images and airborne lidar data / Puistute liigilise koosseisu ja tüvemahu hindamine k-lähima naabri meetodil mitmerindelistes majandatavates segametsades

Abstract.

Nearest neighbour techniques are useful for constructing maps of forest inventory variables based on sample plot and auxiliary data from remote sensing. The most problematic issue of the nearest neighbour technique is possible systematic bias in the estimated values. In this study a 15 by 15 km test site in nemoral multilayer mixed forests was established in Laeva, Estonia. A set of 444 circular sample plots was used as reference set. Airborne lidar data and Landsat-8 Operational Land Imager image were used to construct five different feature variable sets consisting of original variables and alternatively principal components. The response variables were wood volume of first tree layer, wood volume of the second tree layer and main species code. A special test was carried out where a substantial amount of Silver birch dominated plots were removed from the reference set. The wood volume prediction validation was carried out on 89 forest growth sample plots and on 2290 forest stands. Species composition prediction was validated on 986 forest stands. As in many previous studies the results confirmed superiority of airborne lidar variables over spectral variables for wood volume estimation. The first three principal components of airborne lidar variables and first five principal components of all possible original feature variables contained over 99% of the information and performed well in imputations. The imputed wood volume at small values was overestimated and underestimated at large values regardless of used reference set. The feature variable sets containing spectral data performed better for species composition imputation. There was a forest age dependent discrepancy in predicted species proportions: birch and spruce proportions were underestimated in young stands and overestimated in older stands while proportion of aspen had exactly the opposite errors. The lack of fit depended slightly on the feature variable sets. The birch dominated plot partial removal from the reference set changed the predicted proportion of species but did not remove the forest age dependent lack of fit. The result can be important for the studies in which bootstrap samples are used to estimate error statistics for nearest neighbour technique based forest inventory variable maps.

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Factors affecting the distribution patterns of aquatic macrophytes

-617. Edvardsen A., Okland R.H., 2006, Variation in plant species composition in and adjacent to 64 Ponds in SE Norwegian agricultural landscapes, Aquat. Bot. 85: 92-102. Feldmann T., 2012, The structuring role of lake conditions for aquatic macrophytes [Ph.D. Thesis], Estonian University of Life Sciences, Tartu, pp. 182. Fernández-Aláez C., Fernández-Aláez M., Bécares E., 1999, Influence of water level fluctuation on the structure and composition of macrophyte vegetation in two small temporary lakes in the northwest of Spain, Hydrobiology 415

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Long-term changes in the Leucobryo-Pinetum community: interactions between the tree-stand, understorey and moss layer

the Acadian Forest: forest floor, bryophyte community and habitat features. Can. J. Bot. 80: 21-33. Rost-Siebert K., Jahn G. 1988. Veränderungen der Waldbodenvegetation während der letzten Jahrzehnte - Eignung zur Bioindikation von Immissionswirkungen? Forst und Holz 43 (4): 75-81. Sokołowski A. W. 1991a. Zmiany składu gatunkowego zbiorowisk leśnych w rezerwatach Puszczy Białowieskiej. Ochr. Przyr. 49: 63-78. Sokołowski A. W. 1991b. Changes in species composition of a mixed Scots pine

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Species Structure of Plants in the Báb Forest Clearcuts

Abstract

In the paper we have summarized the results of a research which was realized in the Báb forest (Veľký Báb, Nitra upland). The target of the research is the evaluation of species composition in the clearcuts in 2012. In the Báb forest, during spring records there were 80 and during summer records 102 taxa of taxons recorded. The woody plants of spring and summer reports were mainly represented by typical forest species. Moreover, these are woody plants of forest open parts and there are also two invasive woody Ailanthus altissima, Robinia pseudoacacia plants documented. During the summer reports, three new woody plants Clematis vitalba, Lonicera caprifolium, Ulmus minor appeared in the herb layer. Herbs are represented during the spring reports by typical spring ephemeroids, geophytes and forest herbs presenting the spring synusia. During the summer reports, ephemeroids are absent and there were new species, mainly Alliaria petiolata, Convallaria majalis, Lithospermum purpurocaeruleum, Melica nutans of forest herbs reported. In the clearcut areas also clearcut, synanthropic, mainly Cirsium vulgare, Lamium purpureum, Sambucus ebulus, Serratula tinctoria, Torilis japonica and invasive species Aster lanceolatus, A. novi-belgii agg., Erigeron annuus ssp. annuus, Impatiens parviflora occurred. Generally, we can state that the diversity of clearcut plant taxa is high. Taxa are represented by forest woody plants, woody plants of clearcuts, forest open parts and forest edges. Within clearcut herbs, there are typical forest species of oak-hornbeam forests represented, species of clearcuts and human-influenced posts and there are also invasive taxa found

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Thrips (Thysanoptera) of the beech forests of south-eastern Poland

Wciornastki (Thysanoptera) lasów bukowych południowo-wschodniej Polski

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Rebuilding of species composition of xerothermic grasslands in selected research areas in the Ojców National Park

References Andrzejewski H. 1987. Changes in the species composition and structure of the herb layer of a thermophilous oak forest subject to clear cutting. Acta Soc. Bot. Pol. 56 (3), 513-525. Bąba W. 1999. Murawy kserotermiczne w planie ochrony Ojcowskiego Parku Narodowego. Przegląd Przyrodniczy 10 (1/2), 129-136. Bąba W. 2002/2003. Ekologiczne podstawy ochrony muraw kserotermicznych w OPN. Prądnik. Pr. i Mat. Muz. im. Prof. W. Szafera 13, 51-76. Bobbink R

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Factors influencing the species composition and richness of herb layer in old boreo-nemoral forests

References Aavik, T., Püssa, K., Roosaluste, E., Moora, M. 2009. Vegetation change in boreonemoral forest during succession - trends in species composition, richness and differentiation diversity. - Annales Botanici Fennici, 46, 326-335. Adermann, V. (ed.) 2007. Eesti metsad 2006. Metsavarude hinnang statistilisel valikmeetodil. (Estonian Forests 2006. The estimation of forest sources by statistical sampling methodology). Tallinn, Metsakaitse-ja Metsauuenduskeskus. 149 pp. (In Estonian with English summary

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