Bożenna Czarnecka

Clonal organization of populations of Asarum europaeum and Maianthemum bifolium in contrasting woodland habitats

Populations of two rhizomatous species, Asarum europaeum (asarabacca) and Maianthemum bifolium (May lily), were examined in two, and four forest habitats respectively, in the Roztocze National Park (south-eastern Poland). May lily populations were studied in habitats: the Carpathian beechwood, upland mixed fir forest, subboreal moist mixed coniferous forest and bog-alder forest. Asarabacca was studied in two habitats: beechwood and Scots pine community (an 80-year-old plantation). In both the species studied intra- and inter-populational differences of the size of genets in terms of above- and below-ground parts of individuals as well as the biomass and area occupied were observed. In May lily populations the greatest mean number of shoots per genet was found in the fir forest (11.62±3.29), a value almost twice as great as that in the moist coniferous forest and nearly three times greater than in the bog-alder forest. Total rhizome length was also the greatest in the fir forest (351.9±98.7 cm) followed by moist coniferous forest, beechwood and alder forest habitats. In all populations of May lily a greater part of total dry weight biomass is in below-ground organs. The greatest biomass value of a genet was found in the fir forest (4.275 g), the smallest in the bog-alder forest (0.110 g). All populations differed significantly in terms of leaf area, leaf length (with the exception of fir forest and beechwood habitats where the values were the greatest), and leaf width (excluding moist coniferous and bog-alder forests which had the smallest values). In the case of asarabacca, both the mean number of ramets per genet (3.36±0.45 vs. 2.49±0.20) and total rhizome length (40.3±6.4 cm vs. 21.1±1.8 cm) were greater in the beechwood habitat than in the pine community. In the first population genets had 3–5 times greater the total biomass of those from the pine community. Only genets of the latter had proportionately more dry weight biomass in above-ground parts. It seems to be correlated with greater rhizome dieback and disintegration of genets into smaller units. Both populations were significantly different in terms of all examined parameters of leaves. Genets of both the species studied were found to have their own structure of developmental phases that often differed for shoots and rhizomes.

Assessment of flora diversity in a minor river valley using ecological indicator values, Geographical Information Systems and Digital Elevation Models

Ellenberg indicator values (EIV) have been widely used to estimate habitat variables from floristic data and to predict vegetation composition based on habitat properties. Geographical Information Systems (GIS) and Digital Elevation Models (DEM) are valuable tools for studying the relationships between topographic and ecological characters of river systems. A 3-meter resolution DEM was derived for a. 3-km-long break section of the Szum River (SE Poland) from a 1:10,000 topographic map. Data on the diversity and ecological requirements of the local vascular flora were obtained while making floristic charts for 32 sections of the river valley (each 200 m long) and physical and chemical soil measurements; next, the data were translated into EIV. The correlations of the primary and secondary topographic attributes of the valley, species richness, and EIV (adapted for the Polish vascular flora) were assessed for all species recognized in each valley section. The total area and proportion of a flat area, mean slope, slope curvature, solar radiation (SRAD), and topographic wetness index (TWI) are the most important factors influencing local flora richness and diversity. The highest correlations were found for three ecological indicators, namely light, soil moisture, and soil organic content. The DEM seems to be useful in determination of correlations between topographic and ecological attributes along a minor river valley.

Richness of vascular flora in Lublin city, east Poland, under different urban pressure

Cities are commonly described as mosaics of habitats with increasing degrees of human impact along a gradient from the outskirts to the centers, which may lead to both an increase and a decline in species richness and diversity. Data on species richness in the city of Lublin had been collected in a model transect containing 20 1-km2 study squares. We used ordination methods correspondence analysis (CA) and redundancy analysis (RDA), Spearman’s rank correlation, forward selection, and the Monte Carlo permutation test to determine which factors have the greatest effect on species richness in various types of city habitats. There were 795 vascular plant species in squares, with predominance of native (540) rather that alien (255) species. The greatest richness was reported in the city center, where residential areas border railway infrastructure and extensively cultivated agricultural areas. The lowest number of species was found in peripheral areas overgrown by seminatural vegetation. The main factor determining species richness and flora quality in the city is human impact. Species richness of native and alien plants is influenced by the landscape structure created by land-use and land-cover variability, hemeroby level, and the period under urban pressure.

Topographic attributes and ecological indicator values in assessing the ground-floor vegetation patterns

Abstract The paper discusses the question whether geographical information systems (GIS) and digital elevation models (DEM) are useful tools for studying correlations between topographic attributes of a given area, and vascular flora requirements reflected by ecological indicator values (EIVs). The model object was a 4-km-long gorge section of the Sopot river valley (80.5 ha), the Central Roztocze Highlands, South-East Poland. Species lists for 40 ca. 200-m-long and 100-350-m-wide sections, according to the river course, separately for the left and right riverbanks, were made. The analysis of the area was based on a 3-meter resolution DEM. We applied primary topographic attributes: slope, and planar, vertical, and total curvatures and also secondary topographic attributes: solar radiation (SRAD) and topographic wetness index (TWI), as well as other terrain characters: denivelation, total, flat and upslope area of each section. Using the multivariate analyses, we analysed relationships between weighted averages of EIVs for each species and topographic attributes. The GIS and DEM became useful tools for the detection of patterns of species with different habitat requirements. The species number correlated positively with the total and flat area of a section and the TWI, while the denivelation, mean slope and upslope area had a reverse vector. Among the most frequent and abundant herb species, we found several spatial patterns of distribution, namely those of: Maianthemum bifolium, Carex remota, C. acutiformis, Filipendula ulmaria, Dryopteris filixmas, and Urtica dioica. The rarest species represented Ajuga genevensis, Scorzonera humilis, and Stachys palustris patterns.