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Factors affecting the diversity of vegetation of chosen lakeland and riverine peatlands of SE Poland

Factors affecting the diversity of vegetation of chosen lakeland and riverine peatlands of SE Poland

The aim of the study was to present the diversity of peatland vegetation of two regions in south-eastern Poland. We also aimed to determine the relationship between particular edaphic factors as well as the structure of peatland communities and their diversity. The study was conducted in the lakeland peatlands of the Łęczna-Włodawa Lakeland and in riverine peatlands in the river breaks of the Central Roztocze Highlands. The lakeland peatlands are characterized by lower species richness and diversity expressed by the Shannon-Wiener index; yet, they exhibit greater phytocoenotic diversity in comparison to the riverine peatlands of Roztocze. Increased tree density in lakeland peatlands reduces the number of species and renders the communities less diverse. Such physico-chemical properties as soil acidity and content of Ca, and Na ensure species richness in Caricetum lasiocarpae phytocoenoses in the lakeland peatlands.

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Molecular Monitoring Of Bacterial And Microalgal Biocenoses’ Biodiversity In High Loaded Farming Ponds

Abstract

Eutrophication process is a serious problem in water ecosystems. There is a great need to study the relation between the physico-chemical condition of water and the influence of these parameters on the diversity of biological life, especially on changes in the structure of microbiocenoses. The most interesting are bacteria and microalgae, due to the important roles they play in maintaining the balance of the aquatic environment. In this study, biodiversity analysis of eukaryotic microalgae and bacteria in two artificial water ecosystems - fish farming ponds - was performed. Aquaculture was based on IMTA technology, in which every part of the trophic chain plays a significant role in maintaining the balance in the ecosystems. Experimental intensive - extensive systems differed in terms of nutrient loads, ponds were characterized by high loads of organic and inorganic nitrogen and phosphorus. During the experimental period, the physicochemical conditions, quantitative genotypic structure of the two biocenoses being studied and the relation between these factors were monitored and investigated. For the biodiversity analysis, the PCR - DGGE technique was used. The results of preliminary research showed that there is a correlation between nutrient loads, diversity expressed in the Shannon-Wiener Index and the overall condition of experimental systems. Higher loadings of nutrient promote the development of bacteria and microalgae without any influence on the balance in the artificial ecosystem being tested.

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Assessment of Mountain Ecosystems Changes Under Anthropogenic Pressure in Latorica River Basin (Transcarpathian Region, Ukraine)

Abstract

The Carpathian mountain ecosystems have been changed under anthropogenic pressure during last decades. The different types of anthropogenic pressure affect the ecosystem characteristics and functioning. The species composition, species richness and ecological indicator values of 12 ecological factors were compared among 14 habitats: natural, semi-natural, degraded and ruderal ecosystems in different altitude zones. The results show that anthropogenic pressure and altitude gradient influence indices of edaphic and climate conditions. The anthropogenic pressure also affects biodiversity: the highest species richness and Shannon-Wiener index are observed in habitats with ‘intermediate’ disturbances level, while high level of disturbances cause decrease in bio-diversity. The disturbances cause the ecosystem to become susceptible to invasion of alien species, while native species, especially rare, become vulnerable and can disappear.

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Changes in alpine vegetation over 50 years in the Western Tatras (Slovakia)

Abstract

This paper examines changes in alpine vegetation over 50 years in the Western Tatras part of the Western Carpathians Mountains in Slovakia. We focus on the following most widespread vegetation types: subalpine to subnival grasslands (alliance Juncion trifidi Krajina 1933), snowbed vegetation (alliance Festucion picturatae Krajina 1933) and dwarf-shrub vegetation (alliances Loiseleurio-Vaccinion Br.-Bl. in Br.-Bl. et Jenny 1926 and Vaccinion myrtilli Krajina 1933). The historical 1971–1977 sampling dataset was re-sampled in 2016–2017 and our research is based on a comparison of 40 pairs of these relevés. Herein, we studied (i) changes in species frequencies; (ii) changes in phytodiversity and site conditions using estimates of Ellenberg’s eco-indices and (iii) comparison of historical and current relevés over time using the nonmetric multidimensional scaling gradient analysis (NMDS) ordination method. The frequency curves reveal differences; especially in the most frequent species at 37.5−80%, which reach higher values in the current data. The higher 7.5−25% value of medium-frequent species in the historical relevés indicates progressive homogenisation of the examined vegetation. In addition, the Shannon-Wiener index of individual vegetation types revealed no significant differences in diversity or average number of species. The historical relevés included 75 species while 74 were confirmed in the current data. Statistically significant differences were determined in light factor for all three vegetation groups. This was due to the retreat of some light-demanding species. While NMDS indicated changes in Festucion and Vaccinion relevés over time, the Juncion group relevés did not follow this trend, thus confirming their high stability. The observed changes between current and historical data are attributed to changes in climate and altered land use with the cessation of grazing.

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The growth and biodiversity of spruce stands in variable climate conditions – Radziejowa case study

Abstract

In the experiment eight populations of Picea abies were chosen at 100 m intervals between 500 m and 1200 m altitude a.s.l.. In each population wood core samples were collected from 14-19 trees (126 cores total), and measured using a Corim Maxi device. At four of the eight sites (every 200 m in elevation between 500 m and 1100 m a.s.l.), the diversity of ground vegetation was evaluated, and temperature was recorded at every 100 m of altitude.

The highest average radial increment of spruce occurred between the altitudes 800-1000 m a.s.l., which is probably the optimum for spruce. The larger increment indices observed at higher altitudes may signify a high growth potential of spruce. It may also suggest a recent upward shift of the optimum growth zone for this tree species.

In 15 phytosociological records, the presence of 148 plant species forming plant associations: Dentario glandulosae- Fagetum typicum (sub-mountainous and mountainous form) and Abieti-Piceetum, and community Abies alba-Rubus hirtus, was documented. No relationship was found between ground vegetation species diversity (expressed by Shannon-Wiener index) and levels of stand diversity.

The vegetation species diversity varied with the elevation above sea level: the highest plant diversity was found at 500 m a.s.l., and decreased with increasing altitude. The potential increase in air temperatures may result in changes to the altitudinal range of many plant species including trees, and consequently in an upward shift of the boundaries of plant zones; in this case the sub-mountainous and lower mountainous forest zone. In this region, the optimal zone for Norway spruce may be restricted to the highest elevations.

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Structural Composition of Protozooplankton Communities in Relation to Environmental Factors in Shallow Lakes and Reservoirs of Rīga, Latvia

. Kahl. A. (1930-1935). Uriiere ode г Protozoa. Jena 886 pp. Kalinowska K. Gufyiel. A., Kiersztyn. B., Christ, R. J. (2013). Factors con­trolling bacteria and protlsts in selected Mazurian eutrophic lakes (North-Eastern Poland) during spring. Aquatic Biosyst., 9 (9), 14 pp. Keylock. C. J. (2(X)5). Simpson diversity and the Shannon-Wiener index as special cases of a generalized entropy. O'tkos, 109 (1), 203-207. Lakes. T.. Kim. H. O. (2012). The urban environmental indicator “Biotope Area Ratio”. An enhanced approach to

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Gastrointestinal parasites of the Polish primitive horses from the Biebrza National Park

were calculated with Microsoft™ Excel. To characterize the species diversity of parasites, we used the Shannon-Wiener index: H' = –Σn i /Nlog 2 n i /N, where ni is the population density of each of the species and N is the overall density of populations ( Shannon & Weaver, 1949 ). The similarities in the species composition of parasites in different groups of horses were estimated using the Chekanovsky-Sørensen index of similarity (I CS ) ( Pesenko, 1982 ). I CS = 2a/(a + b) + (a + c), where a is the number of common species and (a + b) + (a + c) is the

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