Iwona Dembicz

Scale- and taxon-dependent patterns of plant diversity in steppes of Khakassia, South Siberia (Russia)

The drivers of plant richness at fine spatial scales in steppe ecosystems are still not sufficiently understood. Our main research questions were: (i) How rich in plant species are the natural steppes of Southern Siberia compared to natural and semi-natural grasslands in other regions of the Palaearctic? (ii) What are the main environmental drivers of the diversity patterns in these steppes? (iii) What are the diversity–environment relationships and do they vary between spatial scales and among different taxonomic groups? We sampled the steppe vegetation (vascular plants, bryophytes and lichens) in Khakassia (Russia) with 39 nested-plot series (0.0001–100-m2 plot size) and 54 additional 10-m2 quadrats across the regional range of steppe types and measured various environmental variables. We measured β-diversity using z-values of power-law species–area relationships. GLM analyses were performed to assess the importance of environmental variables as predictors of species richness and z-value. Khakassian steppes showed both high α- and β-diversity. We found significant scale dependence for the z-values, which had their highest values at small spatial scales and then decreased exponentially. Total species richness was controlled predominantly by heat load index, mean annual precipitation, humus content and soil skeleton content. The positive role of soil pH was evident only for vascular plant species richness. Similar to other studies, we found that the importance of environmental factors strongly differed among taxonomic groups and across spatial scales, thus highlighting the need to study more than one taxon and more than one plot size to get a reliable picture.

Traditionally managed patch of Cladonia-Scots pine forest in the Biebrza valley – specifity of the protected forest community shaped by human activity

The path of Cladonia -Scots pine forest located on dune in Biebrza valley (NE Poland) was carefully studied in order to assess the influence of recently obsolescent selection cutting management on terrestrial lichen biota. Transect was located along the dune ridge crossing both lichen rich pine forests and other adjacent communities. Distinctive habitat patches were characterized by releve. Within the releve area measurements of cutting intensity and soil properties were carried out and soil samples were collected for laboratory analyses. It was found, that subsoil properties are rather similar on the whole dune, which indicates the main influence of management intensity on plant communities studied. All known development stages of Cladonio-Pinetum were observed. The characteristic lichen species preferred low organic horizon depth and low canopy closure. These factors are positively correlated with cutting intensity. The studied path was compared with other described patches of Cladonia -Scots pine in Poland and additional proposals of practices urgently needed to conserve these endangered habitat were given. In spite of already practiced slash removal, there are litter raking and complete cessation of clearcuts in favour of the selection cutting management are necessary for Cladonia -Scots pine forest conservation.

Vascular plants of Łempis nature reserve in the Augustów forest (NE Poland)

During the survey of Łempis Nature Reserve (Augustów Forest, NE Poland) 353 species of vascular plants were recorded, including 32 considered threatened with extinction in Poland (7 species from the Polish “red data book” and 32 species from the Polish “red list”). Among them there were 41 species protected under the Polish law, including 19 strictly protected species and four species listed in the Annex II of the EU Habitats Directive. Ten orchid species were recorded, including the most valuable plants of the nature reserve – Cypripedium calceolus, Hammarbya paludosa, Liparis loeselii and Listera cordata. Among 32 noted Cyperaceae species (including 26 members of the Carex genus), there was a number of threatened plants, e.g. Baeothryon alpinum, Carex chordorrhiza, C. loliacea and Eriophorum gracile. Other rare species included Agrimonia pilosa, Cladium mariscus, Laserpitium latifolium, Linnaea borealis, Potamogeton gramineus and Pulsatilla patens. The presence of anthropophytes was significant (4.5% of the flora), probably due to the past forest management practices as well as proximity of settlements. The extremely rich flora, along with pristine wetland ecosystems (mesotrophic lakes, various mire forests and fens), places the Łempis Nature Reserve among the most valuable nature reserves in Poland. key woRDs: red list species, neophytes, ancient forest species, wetland, Cyperaceae, Orchidaceae 2017, Vol. 21(3): 107–113 doi:10.12657/steciana.021.013 108 Paweł Pawlikowski et al.