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Studies on sexual dimorphism in reference to vegetative features and on the sex ratio in different environmental conditions were carried out in lowland populations of dioecious species Aruncus sylvestris. It was shown that female individuals of Aruncus sylvestris produced higher flowering shoots, longer inflorescences, more leaves and longer and broader leaves than the male ones. All listed differences were statistically significant. In populations of Aruncus sylvestris growing in optimum ecological conditions (fertile and wet soil, half-light) the sex ratio M/F is close to 1:1. Changes of ecological conditions along the gradient of fertility, habitat moisture (estimated by the types of phytocoenoses) and intensity of solar radiation caused marked drift of sex structure towards the male domination. Light intensity was the crucial factor for the sex ratio in studied populations. Populations growing in half-light showed sex ratio M/F ≈ 1:1 irrespective of habitat. Those growing in shade and in full light showed significant shift to male dominance. The largest deviation from 1:1 sex ratio (M/F ≈ 1.0:0.2) was observed in extremely unfavorable habitat conditions (full sun irradiance, dry soil, strong competition from Elymus repens (L.) Gould). Obtained results demonstrated that female individuals of Aruncus sylvestris had markedly higher habitat requirements compared with the male ones.
The aim of the paper is to characterize some aspects of site conditions in selected places with the occurrence of heather (Calluna vulgaris) within the certain area of the Toruń Basin affected by military activities. Relations of heathlands to the soil cover appear to focus on the position of heather in the ecological succession on presently developing, young sandy soils and regularities of the heather distribution in a mosaic with grasslands in isolated dune fields. Studies were performed at two sites: Stawki and Chorągiewka.Heathlands of this area are connected with nutrient-poor and dry sandy habitats. In the ecological succession, which proceeds in places previously devoid of the vegetation cover and strongly deflated, they occur as a transitional type of vegetation, displacing plants of initial psammophilous community (Spergulo-Corynephoretum) and later giving place to pine forest. In the soil evolution, they are connected with the intermediate stage represented by arenosols (haplic arenosols) - weakly developed but sufficiently acid soils. On deforested, parallel dunes of the Toruń Valley, there are specific regular mosaics of vegetation and soil. Heather occurs on podzolized soils (albic arenosols, haplic podzols) on north-western slopes. Dry grasslands (Calamagrostis epigejos) cover slopes with south-eastern exposition, with soils eroded down to bed-rock and now regenerating to the stage of arenosols (haplic arenosols). Podzolized soils seem not to be developed under heather but rather under the relics of former pine forests preserved from erosion and deflation on less steep and more moist slopes.
In precise field trials at five localities in the CR within years 2004-2005 the effects of different locality conditions and yellow- and purple- fleshed potato cultivars on ascorbic acid (AA) and total polyphenol (TP) contents in tubers were determined. AA content on average of nine cultivars reached the value 170.3 mg·kg⁻¹ FM and was demonstrably affected by the genotype of cultivar and locality conditions. The highest level was achieved in Marabel cv.; in other eight cultivars AA contents lower by 5-33% were estimated. Among five localities the highest AA content at the locality in lowland region (174 m a. s.) with the warmest and dry climate and light-textured soils was determined. In the case of total polyphenols no significant difference among localities was found, but the tendency to higher TP (by 9-22% as compared to other localities) at the locality Stachy was observed, what was connected with apparently lower temperature during vegetation period at this locality. In Valfi purple flesh cultivar higher by 90% TP content was found as compared with the mean value for yellow flesh cultivars. In the group of yellow flesh cultivars significant differences of TP content among particular cultivars were also determined.
We studied characteristics of basal leaves of Trollius europaeus L. and T. altissimus Crantz, including blade morphology, phenolic acids and flavonoids. We also verified the influence of site conditions on leaf structure. co-chromatography showed mostly quantitative differences in the contents of particular phenolic acids and flavonoids in leaves. Similarly, there were no important morphological differences between the species and with respect to some traits a significant distinction appeared within T. altissimus populations. Additionally, site conditions had an effect on leaf morphology of both examined species. Therefore, based on our results, the separation of two Trollius species is questionable. The study supported the statement that T. europaeus and T. altissimus are not separated species, thus T. europaeus should be divided into two lower taxa in the rank of variety or subspecies.
In this paper, is presented data on the abundance and age structure of natural regeneration of silver fir in permanent plots in Sudety Mts. In the studied plots the abundance of fir seedlings is usually markedly lower than in the well-regenerating Carpathian forest stands. The major reason for this is the lower contribution of fir trees to forest stands in the Sudety Mts. as compared with the Carpathians. In most plots the process of regeneration is long and extended over many years. Largest numbers of seedlings developed in years of good fir cone crops. An important role in the process of natural regeneration of Abies alba in the Sudety Mts. are played by type of site, kind of humus and herb layer density. Most of the studied forest stands in the Sudety are not dense, so the herb layer is well-developed, that strongly restrain fir regeneration especially in fartile soils.
The paper assesses the growth of nine seed stands of Picea abies (L.) Karst. of Istebna. The stands were selected on the basis of the dynamic height growth and good adaptation of their progeny under different site conditions. The d.b.h. increment of trees during the entire lifespan of stands is analysed in detail, especially its magnitude and dynamics during the last twenty years, i.e. from 1982 to 2001.
The population structure of Phragmites australis (Cav.) Trin. ex Steud. was examined in seven categories of overgrowing flood control ditches, differing on time which had elapsed from the last clean-up. Density, biomass, frequency of development stages, as well as the size and habit of the shoots, were determined in the populations. Site conditions in the ditches and the proportion of the common reed in the total biomass of plants were also examined. The rate at which populations in cleaned ditches regenerate is very quick. Three years after the maintenance works in ditches the reed population is already fully regenerated. Well developed reed rushes, which biomass is about 650 g d.w.m⁻², are dominant. Its density amounts to 76 ± 25 shoots m⁻². Flowering and fruiting shoots are the most numerous. The first signs of population regression were observed in the ditches left without cleaning for more than 5 years. Population density is gradually lower, the proportion of generative shoots is reduced, and the reed is lighter and has smaller assimilation area. In the 11-year-old and older ditches the reed is replaced by other plant species, mainly grasses and shrubs.
The aim of the study was to assess the influence of environmental conditions on the composition of endophytic assemblages associated with fir clubmoss, Huperzia selago (L.) Bernh. ex Schrank et Mart. This clubmoss is a cosmopolitan species widely spread in Eurasia and North America, and its gametophytes and sporophytes are colonised by endophytic fungi. Plants for this study were collected in October 2004 and between April and October 2007 from seven European sites, differing in altitude, average annual precipitation, temperature and plant community. Endophytes were isolated on PDA medium (4% potato-dextrose agar) and identified through morphological observations. Different ecological indices were calculated for each site like colonization factor, Fisher’s alpha, Shannon’s diversity, Morista-Horn and Jaccard’s indices. Our results prove that altitude positively correlates with species diversity (Fisher’s alpha) and species richness (number of species). Moreover, the similarity assessed from Jaccard’s (0.66 for Larici-Piceetum sites) and Morista-Horn indices (0.77 for Juncetea trifidi sites) suggest the influence of plant community on fungal endophyte composition.
The study is an attempt to determine variation in the proportions of sapwood and heartwood in the radial and axial sections in stems of common oak (Quercus robur L.), representing the main tree stand (according to Kraft biosocial classification), age classes V (81-100 years) and VI (101-120 years), growing in the fresh mixed forest and fresh forest sites. Sample trees were selected according to Urich I method from four plots (of 1 ha each). For each model tree its crown projection area was determined. After felling all necessary biometric traits of tree stem and live crown were measured. Stems were divided into 2-metre sections, from which centres discs were cut in order to determine selected wood macrostructure parameters and volumes of sapwood rings and heartwood cylinders. Additional discs were cut from breast height and kerf planes of trees. When analyzing results for individual discs and trees arithmetic means of widths (or volumes) of studied wood zones were used. During the study the irregularities were determined of sapwood and heartwood zones in stems. Strong and plus interrelations were found between crown volume and crown projection area (as area of cylinder external surface) and sapwood area at the cross stem section, although some of the correlation coefficients were not significant. Large variation was observed in the proportions of volumes of sapwood and heartwood in individual Kraft’s biosocial classes. Differences were also found in sapwood and heartwood radial share between age classes, and rather small differences between forest site types.
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