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Şahin, B. (2004): Species composition and diversity of epipelic algae in Çatal Lake (Şebinkarahisar-Giresun, Turkey). — Turk. J. Biol. 28 : 103–109. Şahin B. Species composition

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.M.R. and Coomes , D.A. 2007 . Impacts of forest fragmentation on species composition and forest structure in the temperate landscape of southern Chile . Global Ecol. Biogeogr. 16 : 426 – 439

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. Relationship Between Spatial and Temporal Patterns of Species Composition in the Shawnee National Forest Illinois, USA . Ph.D Dissertation. Southern Illinois University, Carbondale. Chandy S

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We established transects under twenty Juniperus virginiana trees that invaded an unburned central Oklahoma grassland within the last 20 years to determine their effects on plant species composition. Species richness and stem density increased as distance from the trunk increased. Stem density was also higher towards the south side of trees. Graminoid, forb and total cover were related to distance from the trunk and transect direction. Ordination revealed weak compositional gradients related to “openness” and compass direction. Woody species tended to be most abundant underneath J. virginiana canopies whereas grass and forb species were most abundant in the prairie. Woody and shade-tolerant species preferentially occurred in north transects and quadrats underneath the tree. Conversely, forbs had highest abundance on edge quadrats whereas graminoids dominated south transects and prairie quadrats. Thus, invasion of grasslands by J. virginiana influences species composition in a spatially complex manner.

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We elaborated and tested a novel operative framework for sampling and analysing fine-scale pattern of plant composition and biomass. We combined presence/absence sampling of plant species with non-destructive biomass estimation. In an open perennial sand grassland, we used 46 m long circular transects consisting of 0. 05 m by 0. 05 m adjoining elementary sampling units. This arrangement allows us to scale across a range of 0. 05 to 20 m. For measuring aboveground green biomass, we applied digital camera sensitive to red and near infrared parts of light spectrum, and we calculated normalised differential vegetation index (NDVI). We used information statistics proposed by Juhász-Nagy to study the association between spatial patterns of production and species composition. Since information statistical functions applied require binary data, we transformed NDVI data into one or several binary variables. We found that not only dominant species but subordinate gap species were also associated to high biomass, although the strength of association varied across scales. Most of the significant associations were detected at fine scales, from 0. 05 to 0. 25 m. At the scales commensurable with quadrat sizes usually applied in grasslands, i. e., from 0. 5 to 2. 0 m, we could hardly find any significant associations between species composition and biomass. We concluded that the novel methods applied proved reliable for studying fine-scale relationships between species composition and biomass.

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Aquatic hyphomycetes or Ingoldian fungi are the major decomposers of leaf litter in temperate aquatic ecosystems. Role of leaf litter quality in structuring hyphomycete communities is intensively discussed among hydrobiologists. Therefore, an adequate sampling strategy of the leaf litter is essential in this field. The present paper aims analysing the appropriate sample size of leaf litter with various diversity and evenness combinations taken from streambeds in the temperate deciduous forest zone.Leaf litter in the streambed was sampled at four stream sections of two tributaries of the Morgó stream in the Börzsöny Mts, Hungary. The tributaries differed in water chemistry, altitude and riparian vegetation. To analyse species number-sample size relations, species saturation diagrams were drawn and statistically evaluated.Results showed that: (1) a sample size of 500 leaves sufficiently describes the species composition of leaf litter taken from streambeds in the temperate forest zone, in cases of low diversity forest stands and high diversity forest stands coupled with high evenness; and (2) for forest sites with high diversity coupled with low evenness values a litter sample composed by 800-1000 leaves is advised to investigate to achieve satisfactory estimation of the species composition of leaf litter.The sampling methods described in this paper are proposed for studies where estimation of leaf litter composition is required to understand the available substrate quality for litter decomposing organisms.

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Habitat boundaries in general and forest edges in particular belong to the central issues in ecology. Theories about community and environmental edge-responses are diverse, but there is a lack of sufficient supporting field evidence: no consensus exists about distinctness and diversity of edges, and the existence of edge-related species. Moreover, as most studies focus on man-made edges, natural forest edges are less understood. We studied xeric forest edges in a wooded-steppe area. Twelve forest patches were selected, and plots were set up within the edges, the forest interiors and the grasslands. Species composition, species richness and Shannon diversity were compared between the three habitat types as well as between differently oriented edges. We identified diagnostic species for all habitats. Local habitat preferences of the edge-related species were compared to their regional preferences. Environmental factors of the different habitats were assessed by using ecological indicator values. Forest edges differed both from forest interiors and grasslands, forming a narrow but distinct habitat type between them. Species composition of the edges was not simply a mixture of forest and grassland species, but there were several edge-related species, most of which are regionally regarded as typical of closed steppe grasslands. Neither shady conditions of the forests, nor dry conditions of the grasslands are tolerated by these species; this is why they are confined to edges. Species richness and Shannon-diversity were higher within edges than in either of the habitat interiors. Ecological indicator values suggested that light intensity and temperature were higher in the edges than in the forests, but were lower than in the grasslands. In contrast, soil moisture was lower in the edges than in the forests but was higher than in the grasslands. There were slight differences between differently exposed edges concerning species composition, species richness and Shannon diversity. We conclude that edges should be considered an integral part of wooded-steppes. Their high diversity may have nature conservation implications. Our study emphasizes that edge species may be confined to edges only locally, but may have a broader distributional range in other areas. These species may be referred to as local edge species. Our results also point out that the very same edge can be interactive and non-interactive at the same time, depending on the characteristics considered.

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Erősen karbonátos, humuszban és káliumban gazdag, de foszforban szegény réti talajú legelőn feltörés után létesített telepített gyepen 10 éven át vizsgáltuk a P- (0, 40, 80, 120 kg P2O5·ha–1),ill. a N-műtrágyázás (0, 120, 200, 280, 360 kg N·ha–1) hatását önmagukban és kombinációikkal a gyep fajösszetételére és termésére. Az előbbiek fajonkénti tömeg %-át becsültük, míg az utóbbit szénaként mértük. A kísérletet esőztetve öntöztük. Főbb megállapításaink: – A gyep fajösszetétele. Telepítéskor a kísérlet egész területét egységes NP-trágyázásban részesítettük azonos fajösszetételű, jól beállt és fejlett gyepállomány kialakítása céljából. Így még a kontrollparcellákon is 2–3 évig megfelelő gyepborítás mutatkozott. Azonban az évek során a fokozódó P-hiány miatt a gyep egyre jobban kiritkult. Az önmagában alkalmazott N-trágyázás a kialakult nagy N-bőség miatt negatív hatást eredményezett. A szóló P-trágyázás nagymértékben fokozta mind a füvek, mind a pillangósok fejlődését és produktivitását. A P-adagok és 10 év átlagában a fű:pillangós:gyom tömegarány 50:44:6%. E kezelésben a füvek közül legnagyobb mennyiségben a réti perje fordult elő, jelentős tömegű réti csenkesz társaságában. Az NP kombinált kezelésekben – 10 év átlagában – a fű:pillangós: gyom tömegarány 82:11:7%-ot tett ki. A kísérlet első évében a réti csenkesz vált uralkodóvá, melyet a 3. évben a csomós ebír váltott fel. A 4. évtől kezdve fokozatosan a réti perje vette át a vezető szerepet, melyet a kísérlet utolsó éveiben megosztott az ismét megerősödött réti csenkesszel. A pillangósok közül az NP-kezelésű parcellákban csak a szarvaskerep maradt meg a műtrágyaadagok növeléséhez igazodó arányban. – A gyep szénatermése. A talaj nagyfokú P-szegénysége miatt a kontroll- és az önmagában N-trágyázott parcellákon elfogadható mennyiségű termés nem alakult ki. A P-trágya az adagjaitól függően nagymértékben növelte a termést, 10 év átlagában 177, 256 és 285%-kal, vagyis 1 kg P2O5-tel az adagok sorrendjében 85, 62 és 45 kg széna többlettermést kaptunk. Még a 120 kg P2O5·ha–1 adag is megbízhatóan növelte a hozamot, annak ellenére, hogy a talajban az évek során jelentős mennyiségű foszfor akkumulálódott. A legnagyobb terméseket az NP együttes alkalmazásával értük el. A N-trágyázás növekedő adagjaival – a P-kezelések és 10 év átlagában – 1,12, 2,11, 2,86 és 3,36 t széna·ha–1 terméstöbbletet eredményezett. A P-trágya termésnövelő hatása ennél jóval nagyobb volt. Az adagok sorrendjében – 10 év és a N-adagok átlagában – 4,80, 6,95 és 7,73 t széna·ha–1 terméstöbbletet idézett elő. Tehát a 120 kg P2O5·ha–1 adag még az NP kombinációban is megbízhatóan növelte a termést. A kísérlet legnagyobb termését 10 év átlagában az N360P120-kezeléssel értük el: 12,89 a kontroll 2,24 t·ha–1 termésével szemben. Az évenkénti szénatermések az idő előrehaladtával, főként az 5. évtől kezdődően jelentősen csökkentek. A kísérlet eredményei is rávilágítanak arra, hogy karbonátos réti talajú legelő helyén telepített gyepen P- és NP-trágyázással nagy és jó minőségű termést adó gyep alakítható ki, nagyon jó műtrágya-hatékonysággal.

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233 Balog, A., Markó, V., Kutasi, Cs. and ÁdÁm, L. (2003): Species composition of ground dwelling staphylinid (Coleoptera, Staphylinidae) communities in apple and pear orchards in Hungary

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) 12 121 129 Markó, V., Merkl, O., Podlussány, A., Víg, K., Kutasi, Cs. and Bogya, S. (1995): Species composition of Coleoptera assemblages in the

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