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.

Partitioning sourćes of ecosystem and soil respiration (R_eco and R_s) is important for understanding how climate change affects carbon cycling. Plant and microbial biomass analyses and daytime measurements of R_eco and R_s were performed for 25 plots in an alpine meadow at elevation 4313 m on the Tibetan Plateau. Plant and microbial biomass were determined by harvesting method and the chloroform fumigation-extraction method, respectively. Respiration fluxes were measured by an automated CO₂ flux system (LI-8100, LI-COR Biosciences, Lincoln, NE, USA). Soil respiration can be estimated by a linear or exponential relationship between R_eco and aboveground plant biomass (AGB). Microbial respiration (R_m) can be estimated by a linear or exponential relationship between R_s and belowground plant biomass (BGB) or by a multiple relationship between R_eco and AGB and BGB. Soil respiration (or R_m) is respiration flux when AGB (or BGB) is extrapolated to zero for the linear and exponential regression methods. Similarly, R_m is respiration flux when both AGB and BGB are zero for the multiple regression method. Our findings suggest that the exponential regression method to partition sources of Reco and R_s may be more appropriate compared to other methods for this alpine meadow of Tibet.

Xanthium sibiricum, an annual weed, unexpectedly and dramatically occupied the exposed drawdown area after water had been impounded for the first time in the newly created Three Gorges Reservoir in China. In order to explain this phenomenon and establish an appropriate management strategy, the effects of constant submersion on seed viability and germination of X. sibiricum were investigated at two constant temperature regimes (25°C and 30°C) under artificial laboratory conditions. The results indicated that the seeds of X. sibiricum exhibited a high level of tolerance of submersion and up to 99% of seeds were viable in each treatment regime. The effect of submersion on germination was not obvious at 25°C until the submersion was prolonged for 180 days, while at 30°C the eventual germination rate of X. sibiricum, even after submergence for only one day, was significantly improved. The speed of germination was also consistently accelerated by prolonged periods of submersion. The proportion of seeds that germinated in all treatments combined was less that 56% due to seed dimorphism, thereby providing a seed bank. We conclude that the interaction between long-term winter flooding and high temperature in summer is the major reason that X. sibiricum was able to occupy the newly exposed drawdown area in the absence of competition. These findings provided further insight into how germination strategy and reservoir water-management regime contributed to this dramatic species outbreak.

Research on soil microorganisms associated with plant roots (endophytes) and their outside habitats (rhizosphere, soil) under exposure to high concentrations of heavy metals in the environment may contribute to an increased knowledge about the effects of unfavorable pollutants in the natural ecosystem and improve the efficiency of remediation processes of degraded soils. The main goal of our study was to evaluate properties of microbial populations inhabiting different but spatially closed habitats: interior of the tree roots — endophytes (Betula pendula L. and Alnus glutinosa L.), rhizosphere and soil not influenced by plant roots at two heavy metal polluted areas in southern Poland where the content of cadmium, lead and zinc ranged 9.2–14.9, 26.2–75.1 and 1080–1559 mg-kg^-1 of dried soil, respectively. In our experiment, we analyzed their density as well as determined the total metabolic activity and ability for utilization of different carbon sources. The density of endophytes (5.76–7.16 log₁₀ c.f.u. × g dw^_1) was higher than the density of bacteria inhabiting outside habitats — the rhizosphere and soil (5.43–5.91 and 5.08–5.57 log₁₀ c.f.u. × g dw^-1, respectively) and was not affected by heavy metal content. However, the total metabolic activity of endophytic populations was strongly influenced by the physicochemical properties of the soil and was significantly lower at more contaminated site. In general, the metabolic activity of endophytes was ∼15 times lower than the activity of rhizobacteria and at the same level or lower than the activity of soil microorganisms. Discriminant analysis revealed a higher utilization of a-Cyclodextrin and D-Xylose by microorganisms isolated from more polluted test site. The use of an artificial neural network (ANN) followed by principal component analysis (PCA) allowed the distinguishing of preferences in the utilization of carbon sources by microorganisms due to tree species but not the zone of isolation — endophytes, rhizosphere, soil.

Our study revealed no significant impact of the metal concentrations present in the soil on the density of microorganisms (bacteria and fungi) inhabiting three analyzed zones (interior of the roots, rhziosphere, soil); however, their total metabolic activity was decreased in more contaminated site. Since the density of endophytes was higher compared to the number of bacteria present in the outside habitats (rhizosphere and soil), and their total metabolic activity was in general lower, we suggest a high specialization of microorganisms associated with the cellular spaces of plant roots compared to other microbial populations.

Plant-plant interactions, which are defined as the effect of one plant on another of the same or different species, are inherently local in nature. Plants interact in both positive and negative ways, which are governed by the same underlying ecological dynamic processes. The Mexican endemic Picea chihuahuana Martínez is a largely untouched tree species and it is therefore an excellent model for estimating genetic potential of plant-plant interactions under natural conditions.

Because of the scarce research examining plant-plant interactions at the genetic level, we tested the hypothesis that specific genetic variants of P. chihuahuana are associated with (and likely selected by) the presence of particular neighbouring tree species. To explore this question, we applied AFLP genotyping to five P. chihuahuana populations in the State of Durango, North-western Mexico.

Under the assumption that the variables genetic variant of P. chihuahuana and nearest-neighbour tree species are directly related to each other, the results show a statistically significant association between such genetic variants - at one AFLP locus in one Picea population - and two nearest-neighbour conifer species (P. chihuahuana Martínez and Pinus arizonica Engelm.). The findings indicate that interactions between genetic variants and species diversity may be crucial in shaping plant communities. However, further studies are required for a better understanding of the possible roles that such associations between genetic variants might play.

Nowadays, genetically modified plants are cultivated in many countries and it is important to consider their safety for surrounding environment. So, the environmental risk assessments of genetically modified plants are evaluated. This assessment consists of an objective evaluation of risk and involves generating; collecting and assessing of information on a GM plant with the aim to determine its impact on human or animal health and the environment relative to non-genetically modified organisms. One of the numerous methods used to investigate the impact of GM plants on the environment is the Terminal Restriction Fragment Length Polymorphism. This method was used for comparison of genetic variation in populations of bacteria isolated from rhizosphere of genetically modified maize MON810 carrying the gene cry1Ab and genetically nonmodified maize. Rhizosphere samples were collected in Slovakia during two years (2008, 2009) in July and September and 16S rRNA gene was amplified from metagenomic DNA using universal eubacterial primers. Differences in the number of terminal restriction fragments between control and GM maize hybrids were not detected. Additionally, variation within bacterial communities composition from rhizosphere of MON810 and non-GM hybrids was not observed, nevertheless negligible differences in composition of bacterial community were observed between two sampling periods (July and September). These changes were observed in non-GM as well as in GM maize hybrids and reflected effects of environment and conditions, no influence of genetic modification. The 16S rDNA clone library creation from rhizosphere sample of MON810 maize followed by DNA sequencing revealed that the Proteobacteria were major group of bacteria and Actinobacteria, Firmicutes, and Chloroflexi were less represented. This study did not confirm any changes in the soil ecosystem, which would have been larger than normal variations caused by external conditions.

In plants, biomass allocation and rhizome morphological plasticity reflect different strategies of adaptation to the environment. The aims of this study were to explore the patterns of allocation to different components of the belowground system, and to evaluate the effects of environmental factors on the plasticity of biomass allocation and rhizome morphology. We conducted a survey of the clonal plant, Scirpus planiculmis, in the Momoge wetland in northeastern China. Samples were collected at three sites. Site I is the washland of a seasonal lake. Site II is a permanent lake. Site III belongs to the bank of a recessive river. The average number of sampled plants was 686.25±91.61 per site. We determined the biomass of different plant parts (aboveground part, root, tuber, rhizome) and measured parameters of rhizome morphology (specific rhizome length, average rhizome diameter). Edaphic factors (soil moisture content, organic matter, available phosphorus, available potassium, pH, electrical conductivity) were included as environmental variables. Differences in biomass allocation patterns were analyzed and multiple regression analyses were used to construct a model. The results showed that the structure of the belowground system varied significantly among the three sites. (1) The tubers accounted for the largest share of biomass in plants at site I; (2) plants at site III showed significantly longer rhizomes than those of plants at site II, while the plants at site II showed larger rhizome diameter; (3) pH was the crucial factor affecting biomass allocation and rhizome morphology, and was negatively correlated with root biomass of S. planiculmis. Based on these results, we concluded that: (1) greater resource allocation to the storage organ (tuber) reflects a conservative strategy to avoid damage and to maintain the potential for recolonization in a frequently disturbed habitat; (2) the morphological plasticity of the rhizome increases the ability of the clone to acquire resources. Shorter rhizomes enable rapid colonization of the habitat and efficient resource use under strong competition pressure, while longer rhizomes are useful to explore new habitats when local resources are insufficient. Our results suggest that ecological niche of S. planiculmis should be reconsidered. It may be more appropriate to classify S. planiculmis as a facultative salt-alkali plant, although a degree of tolerance to salinity and alkalinity is important for the initial formation of a population.

The advantage of the clonal plants over the nonclonal species in colonization of all biomes and biogeographical regions primarily is due to occurrence of two modes of reproduction. The creating of vegetative propagules with high vitality and survivability, enables the spread in the newly colonized site, while seed production increases the chances for successful recruitment of seedlings, ensuring the genetic diversity of the population. The differences in allocation into vegetative reproduction and generative propagation in relation to rising height of adjacent plants was investigated in populations of Serratula tinctoria L., occurring in Molinietum caeruleae meadows localized in Southern Poland. Each locality was represented by randomly established three permanent study plots: dominated by small meadow species (LOW), prevailed by large-tussock grasses (INTER) and overgrown by shrubs and trees (HIGH). In the years 2009–2011 the number of leaf rosettes and length of the longest leaf in rosette (as a measure of allocation in vegetative propagation), as well as height of generative stems, number of capitula per stem and number of seeds per capitulum (as indicators of investment in generative reproduction) were observed.

The allocation in vegetative reproduction decreased along the gradient of vegetation height. The gradually decline of number of rosettes might be caused by lack of free space suitable for establishment of new ramets, whereas the small leaf size could be due to drastically augmentation of shading. The allocation in generative reproduction increased along the gradient of vegetation height. The placement of structures necessary for generative propagation in higher layers of herbaceous canopy, as well as considerable number of capitula and seed production might increase the chances for successful recruitment of seedlings.

On the basis of obtained results combining with published data it should be assumed, that the substantial allocation in vegetative reproduction and the slight investment in generative propagation seems to be sufficient for persistence of Serratula tinctoria populations in patches dominated by small meadow species, while the considerable allocation in generative reproduction could be crucial for maintenance of population viability under competitive conditions.

Climate change scenarios suggest that plants will be exposed to increasing levels of ultraviolet radiation in the future. The dove tree, Davidia involucrata Bill (Davidiaceae) is a rare and endangered tree species in China. Its distribution is predicted to become more montane as the climate warms, exposing it to higher levels of UV-B and different soil conditions. We compared the effects of glasshouse ambient (7.08 uW cm^-2) and increased (13.93 uW cm^-2) UV-B on survivorship, secondary metabolites indicative of radiation damage, and putative defensive responses of Davidia involucrata saplings growing under current and increased nitrogen conditions (5 and 25 g m^-2 a^-1 N). Mortalities were higher among plants exposed to increased UV-B, but only in soils with high supplementary nitrogen. Increases in compounds associated with defense against radiation were more frequently recorded under high supplementary nitrogen conditions. This rare and localised plant is highly sensitive to elevated UV-B when growing in high nitrogen soils, a combination that is likely to increase in the summer.

The aim of the study was to demonstrate the relationship between macroinvertebrate assemblages and aquatic vegetation interacting with chemical and geomorphological factors. The survey was carried out in the catchment of a lowland river in Poland in the year 2009. Macroinvertebrate samples were collected on 19 river sites during two campaigns (spring and autumn) and 13 macroinvertebrate metrics were calculated. Indices were selected to reflect pressures associated with organic pollutants, morphological and general degradation of rivers. Hydromorphological assessment was undertaken according to the River Habitat Survey (RHS). Water samples for chemical analysis were collected monthly during the whole year, and nine chemical parameters were analysed. Macrophyte surveys made it possible to calculate seven parameters. It was found that macroinvertebrates collected in spring and autumn showed very different patterns and that only the spring samples showed a significant relationship between macroinvertbrates and water quality, which means that spring sampling is most important for biomonitoring. Only three macroinvertebrate metrics, i.e. SI_GI (German Saprobic Index), EPT (indicating the relative abundance of Ephemeroptera, Plecoptera and Trichoptera) and MBI (index used for river ecological status assessment), responded significantly to water pollution. Macrophytes and macroinvertebrates responded differently to environmental gradients and these organism groups deliver different information for monitoring.

Semi-natural grasslands managed by mowing and grazing are an important part of European landscape. Orthopterans are considered to be an appropriate indicator to assess the impact of agricultural management on grassland ecosystems. We studied effects of mowing, grazing and two kinds of edges on Orthoptera of submontane hay meadows and pastures in the Hrubý Jeseník Mts. (Czech Republic). Using sweep netting and pan trapping, we sampled orthopteran assemblages associated with the farmland managed for at least five years under Czech agri-environmental schemes. In total we collected 2253 individuals of orthopterans representing 14 species. The short-term impacts of mowing and grazing were tested by multivariate ordination analyses. The results indicate that mowing significantly decreased Orthoptera species abundance. Conversely, the response of orthopterans to grazing was not statistically significant and appeared to be species-specific. The abundance of acridid Gomphocerippus rufus increased substantially with grazing, which is in contrast with its negative response to mowing. The negative influence of mowing on grassland inhabitants can be mitigated by lower mowing frequency and by providing temporary uncut refuges. The results of generalized linear models showed significant increase of both species richness and total abundance of Orthoptera towards the baulks. Therefore, the refuges should be established primarily along grass baulks or similar types of permanent grassy edges. As a general rule an effort should be made when managing grasslands to ensure the highest habitat heterogeneity.

Ectothermal vertebrates regulate their body temperature within definite limits to maintain physiological processes at their optimal levels. Among others, food processing and absorption are strongly temperature-dependent. Deficiency of adequate temperatures limits ectotherms in growth and maintenance. On the other hand, thermoregulatory behavior is costly and should be constrained by many factors. Using artificial thermal gradients (26–44°C), we measured temperature preferences of 10 spiny-tailed agamas (Uromastyx acanthinura) in controlled indoor experiment. Each lizard could choose place in the terrarium before and after feeding. Then, temperature preferences during pre-feeding and post-feeding periods were compared. We found significant increase of preferred temperature after feeding. Detailed view revealed that there is consistent influence of body size: bigger lizards maintained higher temperature during the whole experiment. We hypothesize that bigger potential predation risk on smaller lizards due to their size would force them to choose less optimal conditions.

Negative impacts from application of fertilizers and pesticides in agriculture have been observed since the mid-20th century, when their use rapidly increased. This led to decrease in the number of species connected to the agricultural landscape. So-called integrated farming practices are currently being introduced that aim to mitigate negative impacts on the environment and to stabilize the numbers of wild flora and fauna. A number of studies have examined the positive influence of integrate and organic farming as modern agricultural practices in a European perspective. The positive impact of these practices is particularly evident in plants and invertebrates studied in Italy, Austria, Germany and the UK, for example. There is little such data from Central and Eastern Europe, however, even as the region has specific environmental conditions due especially to the more moderate impact of agriculture there during the second half of the 20th century In this study, we compared the numbers of herbal and bird species on crop fields and meadows managed with conventional versus integrated systems in Southern and Central Bohemia, the Czech Republic. Our analysis included also the effects of land parcel size, position within these parcels and presence of other habitat elements (ditch, tree, field roads, dunghill, field margins — boundaries, bushes, fallow area) in the vicinity of study plots. We found that herbal communities were significantly more species-rich on lands with integrated farming and similar results were obtained in the case of birds, except there was a non-significant effect of integrated farming on bird species richness in meadows. In addition, the species richness of plants decreased as land parcel size increased. In conclusion, herbal and bird communities were shown to benefit more distinctively from integrated farming in Central Europe, where this effect is not considered unambiguous due to the higher overall habitat heterogeneity and historically lower burdening of farmland with pesticides and fertilizers. The results support the idea that it makes sense even here to introduce integrated forms of agricultural practice.

The aim of this study was to determine the influence of human pressure and spatial structure of landscape on the occurrence of populations of small mammals in the environment of a large urban agglomeration. The investigations were carried out in Warsaw, Poland in 17 locations. The study sites were located on both sides of the Vistula River, of different landscape spatial structure, in various distances from the city center, and were subject to different degrees of human pressure. Part of the city located on the left bank of the Vistula River is more strongly transformed by man than the part located on the right bank of the river. A total of 933 specimens of 8 species of small mammals were caught using the live-trapping method (Catch-Mark-Release). The richest species composition was found at the city borders and in rural areas. On the left side of Vistula, the species diversity was lower than on the right side, showing significant negative correlation with the human pressure degree. Such pattern was not confirmed on the right side of the river. The only species to occur in all sites on the left side of Vistula was the striped field mouse (Apodemus agrarius). On the right side of Vistula, the striped field mouse was accompanied by the yellow-necked mouse (Apodemus flavicollis) in all research sites. The results indicate that the degree of human pressure and spatial isolation are crucial for composition of small mammal community. Less advanced urbanization processes in areas on the right bank of Vistula, as compared to districts on the left side, provide better contact between local populations of small mammals, and offer better living conditions to a large number of species, even in areas located in the center of the city

Subterranean life style is characterized by limited food resource and energy consuming burrow behavior. Subterranean rodents are usually recognized as dietary generalists. In the current study, we investigated the species composition of winter caches of plateau zokors (Eospalax baileyi), and the dissimilarity of species composition in caches and in the vicinity of the burrows. We have made our research in Kobresia dominated vegetation at the altitude 3200 m a.s.l. We used the non-parametric method to test the similarities between the relative dry mass of the plant species within caches and their closed vicinity. This method was based on measures of distance between pairs of individual multivariate observations. Our results revealed that although plateau zokors cached most (60) of the plant species found in the vicinity of their burrow systems (66), the cached dry mass was dominated by a few species. Nine plant species accounted for 80% dry mass of plants present in zokors' caches, Polygonum viviparum (50%) and other perennial poisonous forbs constitute 70% dry mass of the caches. Results showed that the dissimilarity between the relative dry mass of plant species within caches and in their vicinity was extremely significant (for Bray-Curtis distance measure, R = 0.355, P =0.000; for Euclidean distance measure R =0.319, P = 0.000). These results showed that plateau zokors don't forage randomly when collecting food for winter caches. We suppose that rather than using a non-selective foraging strategy by dealing with high fiber-content plants, plateau zokors have forged another dietary strategy to meet the energy demands in the evolutionary process: to deal with poisonous forbs.

The aim of this study was to assess the density and diet composition of freeranging dogs in Poland. The study was conducted in a field and forest mosaic in the central part of the country in the years 2005–2011. The density of the free-ranging dogs was assessed during night counts along repeated transect routes. The number of dogs seen and the feasible observation area were recorded to calculate density index for each control. The day and night counts captured data on group composition and penetration range. Diets were studied through scat analyses. The dog density ranged from 2.2–3.1 ind. km^-2 depending on the area. Most dogs were observed alone, and 40% formed groups of 2 to 5 dogs. Most groups were recorded close to buildings, but the group organisation changed (especially during the daytime) with increasing distance from the buildings: 35% of dogs in the village were in groups, but 55% of dogs formed groups at a distance of more than 100 m from the buildings. The night proportion of dogs in groups was approximately 50%, regardless of the distance. Their scats contained mostly cereal given by farmers. The prey remains were game species: roe deer (1.3% of occurrences in summer and 12% in winter), brown hare (3–4%), small mammals (5–9.5%) and birds (approx. 1.5%). The study demonstrated that the abundance of dogs in the rural areas of central Poland may play an important role in the ecosystem.