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The influence of habitat conditions on the plankton in the Białe oxbow lake (Nadbużański Landscape Park)

Abstract

The spatial differentiation of the physico-chemical parameters (KdPAR, pH, DOC, nutrient concentrations) and plankton communities (phytoplankton, Crustacea) was considered in the system: the water column without macrophytes, pleustophytes - lemnids (duckweeds) and hornwort Ceratophyllum demersum. It was demonstrated that at the study sites different habitat conditions occurred, which were related to the macrophyte assemblages. The highest values of the phytoplankton biomass and the greatest algal biodiversity were found in the site without vegetation, in both species-specific and functional terms. Zooplankton, dominated by Copepoda, reached the greatest density and species diversity at the Ceratophyllum site. Despite the substantial differentiation of habitats, the plankton diversity was quite low.

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

. Meier, E., Paal, J., Liira, J., Jüriado, I. 2005. Influence of tree stand age and management on the species diversity in Estonian eutrophic alvar and boreo-nemoral Pinus sylvestris forests. - Scandinavian Journal of Forest Research, 20, 135-144. Naumburg, E., DeWald, L. E. 1999. Relationships between Pinus ponderosa forest structure, light characteristics, and understory graminoid species presence and abundance. - Forest Ecology and Management, 124, 205-215. Niemelä, J. 1999. Management in relation to disturbance

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Windstorms as mediator of soil nematode community changes: Evidence from European spruce forest

Summary

Nematode communities in a Norway spruce forest in High Tatra National Park, Slovakia were monitored for the period of several years (2006 and 2013). Unfortunately, in May 2014 natural windstorm damaged the forest. This disastrous event, together with preliminary obtained results allowed us to compare the direct impact of windstorm damage of forest habitat on soil nematode assemblages. The forest destruction by windstorm had a significant effect on the total nematode abundance, the abundance of omnivores and herbivores, as well as the nematode species diversity. The most dominant species, representing 55 % of the total nematode fauna, in the plot studied were Acrobeloides nanus followed by Malenchus exiguus, Filenchus vulgaris, Plectus communis, Plectus parvus and Tylencholaimus mirabilis. The abundance of bacterivorous signifi cantly increased after the windstorm, meanwhile the abundance of omnivores, fungivores, and herbivores ectoparasites and epidermal/root hair feeders showed an opposite trend. Of the evaluative indicators, Shannon species diversity (H’spp), maturity index (MI), maturity index 2-5 (MI2-5), sigma maturity index (ΣMI), enrichment index (EI) and structure index (SI) decreased significantly after windstorm. The EI and SI indexes characterized soil ecosystems before windstorm (2006 - 2013) as maturing with low or moderate disturbance, but soil ecosystems shortly after the windstorm (2014) were degraded and nutrient depleted. This also corresponded with graphical display of metabolic footprints characteristics of soil food web. Overall, the nematode communities differed significantly before and after forest damage. These results suggest the role of nematode communities as indicators of environment condition quality or its disruption.

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Fungal Diversity And Seasonal Succession Under Invasive Moss Campylopus Introflexus And Other Plants In Disturbed Peatlands

Abstract

The distribution of invasive moss Campylopus introflexus (Hedw.) Brid. may have negative influence on natural restoration of plant cover in peatlands due to the accumulation of heavy decomposing residues and suppression of the growth of microorganisms in peat. Species composition of fungal communities and seasonal succession under mosses C. introflexus and Polytrichum strictum, vascular plant Calluna vulgaris and bare peat were studied in two naturally regenerating disturbed peatlands in Lithuania. Cultivable fungi were isolated from peat and enumerated by applying the serial dilution plate technique. A total of 66 species of fungi ascribed to 21 genera (among these 30 species from 13 genera under moss C. introflexus) were identified. Fungus species of the genera Penicillium, Trichoderma, Mortierella and Paecilomyces dominated. The highest diversity of fungal species was found in Laukėsa under Calluna vulgaris. Differences in the structure of fungal communities were found in Mūšos Tyrelis in autumn and in Laukėsa in spring. Significant differences in species diversity under various plants were obtained only in summer. The Gleason species diversity index for peat under C. introflexus was not very high (1.77–2.58) in different seasons. Fungal species composition under moss C. introflexus did not show pronounced characteristic peculiarities compared to other plants and was similar to that in bare peat. The obtained data are important for the prediction of fungal community succession in peatlands and biodegradation level of plant residues.

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Woodland reserves within an urban agglomeration as important refuges for small mammals

Abstract

The aim of the study was to determine the species richness (S, Chao- 1 index) and diversity (Shannon-Wiener H’ index, diversity profiles) of small mammal assemblages in woodland reserves in an urban agglomeration and to compare the similarity of assemblages (with the use of Ward’s method) in terms of proportions of small mammals connected to the habitats of different level of naturalness. The work was conducted from 2004-2015 at 9 woodland reserves in Warsaw (Poland). On the basis of the analysis of pellets of tawny owls Strix aluco, 2792 individuals were identified (24 species). Reserves supported from 7 to 16 of the small mammal species, the highest overall number of species estimated (Chao-1) was 19. Species present in every reserve were Apodemus flavicollis, A. agrarius, Rattus norvegicus, Sorex araneus and Talpa europaea. Least frequent were Microtus agrestis and M. subterraneus. Seven species of bats were detected. Species diversity was lower in the biggest forest complexes, where forest rodents dominated small mammal assemblage. The heterogeneity of habitats within reserve and in the surroundings, in combination with limited human-interference, resulted in an increase in the species diversity. Overall, the reserves under study were an important refuge for small mammals within the Warsaw agglomeration. However, safeguarding of adjacent areas against excessive anthropogenic change is needed and ecological corridors that link different areas need to be retained.

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Distribution and Diversity of Gelatinous Zooplankton in the South Eastern Arabian Sea, Kanyakumari to off Kollam

Abstract

An attempt was made out to study the distribution and diversity of gelatinous zooplankton in the South Eastern Arabian Sea in the region Kanyakumari to off Kollam. A total of 19 species belonging to 8 groups such as chaetognaths, siphonophores, Hydrozoa and Scyphozoa of the phylum Cnidaria, ctenophores, appendicularians, doliolids and salps were recorded. Chaetognaths were not only predominant group, but also the most numerous. Sagitta enfl ata was the most widely distributed chaetognath species from most of the stations studied. Th e siphonophores were the second most abundant group. Shannon-Weaver species diversity index (H′), Margalef’s species diversity index (D) and Pielou’s species evenness (J′) of gelatinous zooplankton were found to be higher from the off shore, Kollam (Station 10) and minimum from the inshore, the Kanyakumari (Cape) West (Station 1). Diversity of gelatinous zooplankton was found to be positively correlated with atmospheric temperature, sea surface temperature and pH. A continuous seasonal study should be conducted to understand the clear impact of physical and chemical factors on the distribution and diversity of gelatinous zooplankton along this region.

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The succession of saproxylic beetles (Coleoptera) on windthrow areas in the Scots pine stands of the Piska Forest

Sukcesja saproksylicznych chrząszczy (Coleoptera) na powierzchniach pohuraganowych w drzewostanach sosnowych Puszczy Piskiej4

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Cladocera record from Budzewo (Skaliska Basin, north-eastern Poland)

ABSTRACT

The sediment sequence from Budzewo (Skaliska Basin, north-eastern Poland) contains cladoceran records beginning from the early Holocene. A total of 33 Cladocera taxa were identified in the entire sequence. The cladoceran fauna of the initial stage of palaeolake history in the Preboreal shows high similarity to early Holocene Estonian and Scandinavian records. Benthic Alonella nana was dominant at that time. After that, probably during the Boreal and early Atlantic periods, Cladocera species diversity increased and planktonic forms (bosminas) became dominant, pointing to a rise of water level. The species composition indicates that the lake was meso- to eutrophic. The lake began to shallow during the middle Atlantic. The process was completed in the Subboreal and the lake transformed into a bog. The fall in water level and finally the terrestrialization of the lake is correlated with similar processes recorded in other sediment sequences in northern Poland, suggesting that this event may have been driven by regional factors such as lower precipitation.

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Oribatid mites (Acari, Oribatida) of various habitats in southern Andalusia (Spain)

Oribatid mites (Acari, Oribatida) of various habitats in southern Andalusia (Spain)

Oribatid mites were investigated in some habitats (litter under cypress, pine and larch trees, and patches of grasses, mosses and lichens) in southern Andalusia (Spain) in August 2005. The studied communities of oribatid mites were rather poor in terms of abundance and species diversity. The density of mites in cypress litter from the mountains (Granada, Ronda) was distinctly higher than in the coastal area (Benalmádena), which was probably caused by climatic conditions. The Oribatida achieved the highest density in grassy patches in Granada, but most species occurred in cypress litter from Ronda. Among oribatid species, Oribatula frisiae reached the highest density; also O. tibialis and Haplochthonius simplex were relatively abundant. Some species of Oribatida were rich in juveniles, but the age structure of species greatly depended on the kind of litter.

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Contribution to the diversity of soil mites (Acari, Gamasida) in southern Croatia (Dalmatia), with some ecological and zoogeographical notes

Contribution to the diversity of soil mites (Acari, Gamasida) in southern Croatia (Dalmatia), with some ecological and zoogeographical notes

The species diversity of soil gamasid mites (Acari) in southern Croatia (Dalmatia) was studied in August 2002. In the Krka National Park, Brač Island, and near the town of Makarska, 320 samples were collected from various microhabitats: soil, grass and moss ground cover, wet moss, needle litter, moss covering tree trunks, and decaying wood). Altogether, 2097 mites of 56 gamasid species were recorded. Dominant species were: Polyaspis patavinus (Brač Island), Zercon fageticola (Makarska), and Cheiroseius serratus (Krka National Park). Analyses of ecological preferences and zoogeographic distribution were made for Polyaspis patavinus, Cheiroseius serratus, Zercon fageticola, Z. berlesei, Z. athiasi, Asca nova and A. aphidioides.

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