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The transformations of field communities with Illecebrum verticillatum L. (Cariophyllaceae) on the borderlands of its European range (Central Eastern Poland)

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Skrajna T. , Gozdowski D. , Ługowska M.

Polish Journal of Ecology

2014

tom Vol. 62, nr 1

3--15

Changes in field communities with Illecebrum verticillatum at the north-eastern limits of the species range in Poland were recorded with the phytosociological method over the years 1994–2010. The material studied consisted of 136 phytosociological relevés which were subjected to numerical classification and ordination according to habitat gradients by the Detrended Correspondence Analysis (DCA). Changes in communities and habitats were assessed using the following indicators: species richness, the Shannon-Weiner index of biodiversity (H), Simpson’s index of domination (C) and floristic value (FV). The values of these indicators were statistically analysed using the Kruskal-Wallis test at P <0.05. Spearman’s rank correlations were calculated using Statistica 10 to determine relationships between the indicators analysed. On the basis of numerical classification 7 types of phytocoenoses were identified, representing communities at the initial and final phases of the study. At the beginning the communities included: Arnoserido-Scleranthetum with Illecebrum verticillatum, in stubble fields and Spergulario-Illecebretum verticillatum and Digitarietum ischaemi with Illecebrum verticillatum in root crops; at the end of the study they included: Vicietum tetraspermae and the community with Aperion spica-venti in cereals and the diverse, floristically common association Echinochloo-Setarietum. The communities identified reflected changes in the phytocenoses of the permanent sites due to intensification of field production. The comparison of indicators of species number, index of biodiversity and index of domination revealed significant differences. The analysis of habitat indicators according to Ellenberg demonstrated that soil temperature and moisture decreased whereas soil pH and nitrogen increased. The comparison of the taxonomic value of a species group for the association Radiolion linoidis and floristic value of communities revealed that species from the from the alliance R. linoidis were disappearing at a rapid rate.

Morphological and genetic diversity of Isopyrum thalictroides L. (Ranunculaceae) populations of isolated forest fragments of different sizes in East Central Poland

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Skrajna T. , Kubicka H. , Ługowska M.

Polish Journal of Ecology

2015

tom Vol. 63, nr 1

23--37

Isopyrum thalictroides is classified as an indicator species of the socalled ‘old-growth forests’. It occurs in shady deciduous forests and is a characteristic species of the order Fagetalia silvaticae. In many parts of Europe and Poland, it is classified in Red Lists of endangered species with different threat levels. Studies of an occurrence of I. thalictroides were carried out in the years 2000–2002 and 2010–2012 to examine changes in the abundance and morphological and genetic diversity of populations inhabiting small mid-field forest fragments (populations 2–4) and a compact forest (1 population), all located in east central Poland. Isopyrum thalictroides cover declined drastically at all isolated sites (from 83 to 93%) whereas the whole species diversity of these phytocenoses increased. By contrast, in the compact forest both, the area occupied by I. thalictroides population and the total community composition only slightly changed over time. When I. thalictroides plants sampled from all studied sites were compared in terms of the biometrical characteristics, populations 3 and 4 were found to be most similar, population 1 was less similar and population 2 was the most different of all populations, probably due to strong anthropogenic pressure. Electrophoretic analysis of seed and leaf storage proteins of Isopyrum thalictroides obtained from the four sites demonstrated that the populations were quite similar genetically, no matter how distant they were from each another. Population 2 was the most diverse, followed by population 1 whereas populations 3 and 4 were the most similar. A decreasing genetic distance in the I. thalictroides population would lead to inbreeding as seed setting by the plants will be poorer and the seeds will be less viable, which will result in a lower number of plants per a given area. The decreased gene pool indicates that the population of I. thalictroides is threatened with extinction in this area. Therefore, it is warranted to undertake some conservation measures to protect the species; hence the need arises to monitor it.