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Abstract

Plant species diversity is threatened in many agricultural landscapes due to the changes it has to undergo. Although the modification of the agricultural landscape pattern is observed across Europe, both extensive and intensive agricultural landscapes still co-exist in Poland. The objective of the study was to examine the flora in field margins in intensively and extensively managed agricultural landscapes, located across three regions in SE Poland. The flora was compared with respect to species richness, diversity, and evenness indices. Detrended correspondence analysis was employed to characterise variation in species composition. Agricultural landscape type made a higher contribution than the topography or geology to species richness and composition in field margins. Field margins function as important habitats for general vascular plant species diversity and are useful for the conservation of rare, threatened, endangered or bee plants. A significant decline in species diversity was observed over a distance of 1000 m from the habitat elements. Plants growing on field margins are mainly perennials; however participation of annuals clearly increases in intensive landscapes. The participation of wind-dispersed species decreased in an open-spaced intensive landscape. Animal-dispersed plants predominated in an extensive landscape with forest islands. Irrespective of landscape type, native species predominated. However, these habitats create the biota and corridors for alien-invasive species as well.

Abstract

During the study on myxomycete species diversity in Bitsevsky Park (Moscow), a new to Russia species Trichia papillata Adamonytė was recorded. It is characterized by stipitate sporangia on well-defined striated stalks. Dehiscence by 6–8 well-defined small peridial plates. The main feature of the species is conspicuous dark warts on the peridium, composed of granular material. The warts are located in the centre of most peridium plates. The paper presents data on the ecological features and distribution of this species as well as iconography and illustrations of morphology, obtained using light and scanning electron microscopy.

Abstract

Species diversity of algal communities of sphagnum epiphyton was studied in six mountain and plain mires of the Subpolar Urals (Russia). A total of 154 species and intraspecific taxa from six divisions were identified. The highest species richness was recorded for Bacillariophyta (96 taxa) and Charophyta (33) divisions. Species Kobayasiella parasubtilissima, Tabellaria flocculosa and Eunotia lunaris had high abundance. Dominant communities were often formed by Eunotia lunaris, E. mucophila, Kobayasiella parasubtilissima and Pinnularia subcapitata. CCA analysis showed that conductivity and altitude above the sea level are the main factors affecting the development of algae in the studied mires.

Abstract

The first ever liverwort and hornwort checklist is provided for Paraguay. Despite the high level of biological diversity in Paraguay, there remain very few intensive collecting efforts for liverworts and hornworts in the region since the late 1800’s. We report 2 hornwort taxa and 71 liverwort taxa. The list is based on almost 100 literature references, including monographs, regional studies, and molecular investigations. Given the dramatic loss of habitats in Paraguay coupled with high species diversity in other organisms, further collecting of liverworts and hornworts is critical. There is also the potential to use historical records with contemporary collections to investigate the impact of habitat loss in the area.

species of genus Metaphycus Mercet (Hymenoptera: Chalcidoidea: Encyrtidae), parasitoids of scale insects. Systematic Entomology , 25: 147-222. Habibi Badrabadi, S., Khayrandish, M. and Mohammadi-Khoramabadi, A. 2017. Faunistic survey and species diversity of parasitoid wasps of Pimpiliformes and Ichneumoniformes Groups (Hymenoptera: Ichneumonidae) in Yazd Province, Iran. Taxonomy and Biosystematics , 32: 4-20. Hafez, M.B. 1988. Population fluctuations on parasites of California red scale, Aonidiella aurantii (Mask.) (Hem.: Diaspidae) in Alexandria. Journal of

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.

Abstract

The paper provides data on macromycete and myxomycete species diversity and distribution in Asveja Regional Park located in eastern Lithuania. A total of 326 species of macromycetes and 33 species and intraspecific taxa of myxomycetes were recorded. Five species, Eocronartium muscicola, Mycena megaspora, Neobulgaria pura, Pachyella violaceonigra and Skeletocutis papyracea, were reported for the first time in Lithuania. Twenty species listed in the Red Data Book of Lithuania were recorded during this study. Distribution and habitats of rare and endangered fungus and myxomycete species are discussed

Abstract

We examined the light sources and illuminated environments in Sopron’s public areas and studied the impact they had on the composition of macrolepidopteran moth communities. We employed light traps with three different light sources in three differently illuminated environments (seminatural, transitional, urban) on 60 occasions during the summer period of 2012-2013 and 20 times in the seminatural area in the spring and autumn of 2014. In the first two years, we evaluated the number of individuals; in year three, we evaluated the number of species. In the first two years, the high-pressure sodium light in the seminatural site trapped the largest number of nocturnal lepidopteran specimens (2,569), while the mixed HMLI light trapped the most individuals in the transitional (1,098) and urban (822) areas. Based on the average number of individuals the first two years, we compared the locations and light sources. In terms of average number of specimens collected, significant differences emerged between two light sources and two locations. When we completed the species diversity index, we determined the compact fluorescent tube in spring and the high-pressure sodium light in the autumn showed the greatest values.

Abstract

Physical and chemical characteristics of habitats and species diversity in streams and rivers are strongly influenced by the catchment area. We analysed the influence of selected environmental and spatial variables on the diversity and species composition of epilithic diatom communities in periphyton. Samples were collected along the river course in a torrential river the Kamniška Bistrica. Sampling sites were selected in reaches distributed from the source to the outlet of the river and were under different influences from the catchment area and with different physical and chemical characteristics. The most common and dominant diatom species in the periphyton community were Achnan-thes biasolettiana and A. minutissima. Achnanthes species often inhabit rivers and springs with moderate organic pollution. Another common diatom taxon was Gomphonema pumi-lum - a key species indicating oligosaprobic conditions. The results of the canonical cor-respondence analyses revealed that variance of the periphytic diatom community was explained by water temperature and conductivity as well as altitude. Diatom species richness was positively correlated with saprobic index values and abundance of filamentous algae in the river bed indicating a relatively low organic matter and nutrient input into the river system.

Abstract

The Rogoznica Lake marine system is a small, karstic, naturally eutrophic and euxinic marine environment. Abundance and temporal distribution of phytoplankton was investigated in relation to environmental conditions in the period from 1998 to 2013. The 36 determined diatoms contributed 90% of the total phytoplankton abundance. The diatom composition is characterized by low species diversity and high single species abundance (up to 107 cells L-1). There were, on average, 2.6 diatom species per sample (maximum 14 diatom species per sample) reflecting extreme environmental conditions. Dominant diatoms Thalassionema nitzschioides, Cyclotella choctawhatcheeana, Dactyliosolen fragilissimus and Chaetoceros curvisetus occurred repeatedly and were alternately dominant in the lake during the whole research period. Some diatoms were dominant only in limited period, like Cyclotella choctawhatcheeana (evident since 2001), and Pseudo-nitzschia spp. (evident in the period 2002 to 2009). It appears that the interplay of environmental conditions such as variability in thermohaline and redox conditions, nutrient and reduced sulphur concentration influence the phytoplankton development and abundance in the lake.