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51.
The distribution and abundance of cave-dwelling bats were investigated in the Thrace region of northwest Turkey. Data were collected in two periods, January-March and April-May 2001, from 32 underground sites, 25 of which had not been surveyed previously. Approximately 76,000 bats representing 13 species were recorded. The most abundant species were Miniopterus schreibersii, Rhinolophus euryale, Myotis myotis/blythii, Myotis capaccinii, and Rhinolophus ferrumequinum. The roosts were evaluated for their conservation importance. The most important sites in Turkish Thrace are Dupnisa and Koyunbaba. The Dupnisa Cave serves as a hibernaculum to approximately 28,000 bats representing five species. The Koyunbaba Cave is a nursery roost to approximately 23,000 bats of six species. Presently, none of the caves in the region has adequate protection and some bat populations are under serious threat.  相似文献   
52.
Particle size distribution (PSD) is a major soil characteristic, which is essential and commonly used for the development of pedotransfer functions (PTFs) to estimate the water retention of soils. The laser diffraction method (LDM) became a popular alternative to the standard sieve‐hydrometer method (SHM) of PSD measurement. Unfortunately, PSDs determined with LDM and SHM methods differ sometimes substantially. Moreover, it is claimed that the laser diffraction method underestimates finer fractions in favor of coarser fractions. Several authors have tried to elaborate on methods to recalculate LDM PSD into its SHM counterparts, but no universal methodology has been developed to this date. In this paper, we use PSD determined by LDM directly for PTF development and compare it with the classical PTF approach based on PSD measured by SHM. Four different PTF models based on LDM particle size distribution data were developed, with different PSD characteristics taken as the models' input variables. The possibility of using alternative PSD characteristics, such as deciles, area moment mean and volume moment mean, for PTF development was examined. The accuracy of PTF models constructed on the basis of LDM‐measured PSD was comparable with that of the developed models using texture data obtained from SHM, giving approximately the same RMSE and R2 values. Our study shows that LDM‐measured particle size distribution may be directly used for PTF developments without any recalculations to their sieve‐hydrometer counterparts.  相似文献   
53.
Mechanisms for Translocation of Heavy Metals from Soil to Epigeal Mosses   总被引:1,自引:0,他引:1  
The mechanisms for translocation of heavy metals from soil to epigeal mosses were investigated. The first mechanism was demonstrated for 137Cs and involved the uplifting of the pollutant-containing dust from the soil, followed by the local secondary deposition on surfaces of epigeal mosses and epiphytic lichens. The second mechanism involved the diffusion of metal cations from the soil through water wetting the moss into the gametophyte. The mechanism was demonstrated by measuring the electric conductance of wetted gametophytes with single ends immersed in solutions of Cu and Na salts. In addition, the concentrations of Cu and Cd were compared in moss samples exposed to the natural soil and to the soil contaminated with the metals. The exposition to the contaminated soil resulted in the statistically significant increase of metal concentrations in the gametophytes.  相似文献   
54.
The concentrations of selected metals—Cr, Ni, Cu, Zn, Cd, and Pb—were determined in the samples of Hypogymnia physodes lichen and Pleurozium schreberi moss collected in Polish and Czech Euroregions Praded and Glacensis. More specifically, the samples were collected in Bory Stobrawskie, Bory Niemodlińskie, and Kotlina K?odzka (Poland) and in Jeseniki (Czech Republic). The concentration of metals in the samples was measured using the atomic absorption spectrometry (flame AAS technique and electrothermal atomization AAS technique). The results were used to calculate the comparison factor (CF) that quantifies the difference in concentration of a given bioavailable analyte × accumulated in lichens and mosses: CF?=?2 (c x,lichen ? c x,moss) (c x,lichen + c x,moss)?1. The values of CF greater than 0.62 indicate the most probable location of heavy metals deposited in the considered area. In this work, the method was used to show a significant contribution of urban emissions to the deposition of heavy metals in the area of Bory Stobrawskie and in the vicinity of K?odzko City.  相似文献   
55.
ABSTRACT

Disease development in plants is strongly dependent on weather conditions, with temperature playing a particularly significant role by influencing latency period duration. Using two models describing the relationship between latency period and temperature, we performed simulations aimed at predicting changes in the latency period of leaf rust (Puccina recondita f. sp. tritici) on triticale in response to expected climate change. The simulations were based on meteorological data recorded in the period 1986–2005 at locations representing 16 provinces in Poland and based on values obtained after transformation of the observed data to reflect temperature changes under four scenarios (RCP2.6, RCP4.5, RCP6.0 and RCP8.5) according to the giss_e2_r climate model. In all scenarios, the results for the two triticale cultivars studied, Witon (vulnerable to P. recondita) and Gniewko (less susceptible), showed a threat of faster development (shorter leaf rust latency period) on triticale triggered by climate change in south-east and south-central Poland than in other regions. The results also showed an increased probability of future regional diversification of leaf rust latency period duration on vulnerable triticale cultivars, opportunities for earlier start of leaf rust epidemics on triticale in Poland and an increase in ?nal disease severity in comparison with 1986–2005.  相似文献   
56.

Purpose

The impacts of fly ash on the chemistry of forest floors were previously described in literature, while impacts on soil properties were less recognised. Soil investigations were focussed mainly on increases of pH and base saturations in surface horizons. The purpose of this study was to describe the influence of alkaline fly ash blown out from the dumping site of a lignite-fired power plant on pH changes of ectohumus horizons of Podzols and the morphology of deeper horizons.

Materials and methods

We investigated the soil profiles of Podzols derived from loose quartz sand and developed under pine forest surrounding the dumping site of the power plant Be?chatów, central Poland. In the vicinity of the fly ash dumping site, five Podzol profiles located at a distance of 50 m from the dumping site were investigated, as well as soil profiles located along the transect set at distances of 50, 300, 800 and 2000 m from the dumping site. Control profiles were located at a distance of 7.3 km from the dumping site. Soil morphology was described in the field and the following properties were determined: soil texture, hydrolytic acidity, exchangeable cations, total organic carbon and total nitrogen content.

Results and discussion

The pH values of Podzol ectohumus horizons located close to the dumping site ranged from 6.01 to 7.34 compared to a range of 3.08–3.72 in the control. Ectohumus horizon located 300 m from the dumping site showed a pH range of 4.13–4.26, while at a distance of 800 m, the pH values did not differ from those of the control site. The upper part of the eluvial soil horizons located close to the dumping site had been transformed into transitional AE horizons in which humic substances translocated from ectohumus horizons were accumulated. Moreover, the organic carbon content of this horizon increased compared to the carbon content of the illuvial Bs horizon located below it. Under the influence of alkalisation of upper horizons, the illuvial Bhs horizons vanished and were transformed into Bs horizons.

Conclusions

Changes in soils affected by fly ashes are connected with alkalinisation of ectohumus horizons. Podzolisation processes can be reduced or even completely stopped regarding the distance from the dumping site. Eluvial Podzol horizons located close to the dumping site may be transformed into AE horizons in which humic substances translocated from ectohumus horizons are accumulated. Due to transformation and translocation of organic components, Bhs horizons can be transformed into Bs horizons.
  相似文献   
57.
The objective of this research was the evaluation of the effects of exogenous added surfactants on hydrocarbon biodegradation and on cell surface properties. Crude oil hydrocarbons are often difficult to remove from the environment because of their insolubility in water. The addition of surfactants enhances the removal of hydrocarbons by raising the solubility of these compounds. These surfactants cause them to become more vulnerable to degradation, thereby facilitating transportation across the cell membrane. The obtained results showed that the microorganism consortia of bacteria are useful biological agents within environmental bioremediation. The most effective amongst all, as regards biodegradation, were the consortia of Pseudomonas spp. and Bacillus spp. strains. The results indicated that the natural surfactants (rhamnolipides and saponins) are more effective surfactants in hydrocarbon biodegradation as compared to Triton X-100. The addition of natural surfactants enhanced the removal of hydrocarbon and diesel oil from the environment. Very promising was the use of saponins as a surfactant in hydrocarbon biodegradation. This surfactant significantly increases the organic compound biodegradation. In the case of those surfactants that could be easily adsorbed on cells of strains (e.g., rhamnolipides), a change of hydrophobicity to ca. 30-40% was noted. As the final result, an increase in hydrocarbon biodegradation was observed.  相似文献   
58.
Water, Air, & Soil Pollution - The effect of exogenously added sodium dodecylbenzenesulphonate (SDBS) surfactant on biodegradation of a mixture of straight-chain aliphatic hydrocarbons...  相似文献   
59.
60.

Background

Population genetic diversity and structure are determined by past and current evolutionary processes, among which spatially limited dispersal, genetic drift, and shifts in species distribution boundaries have major effects. In most wildlife species, environmental modifications by humans often lead to contraction of species’ ranges and/or limit their dispersal by acting as environmental barriers. However, in species well adapted to anthropogenic habitat or open landscapes, human induced environmental changes may facilitate dispersal and range expansions. In this study, we analysed whether isolation by distance and deforestation, among other environmental features, promotes or restricts dispersal and expansion in stone marten (Martes foina) populations.

Results

We genotyped 298 martens from eight sites at twenty-two microsatellite loci to characterize the genetic variability, population structure and demographic history of stone martens in Poland. At the landscape scale, limited genetic differentiation between sites in a mosaic of urban, rural and forest habitats was mostly influenced by isolation by distance. Statistical clustering and multivariate analyses showed weak genetic structuring with two to four clusters and a high rate of gene flow between them. Stronger genetic differentiation was detected for one stone marten population (NE1) located inside a large forest complex. Genetic differentiation between this site and all others was 20% higher than between other sites separated by similar distances. The genetic uniqueness index of NE1 was also twofold higher than in other sites. Past demographic history analyses showed recent expansion of this species in north-eastern Poland. A decrease in genetic diversity from south to north, and MIGRAINE analyses indicated the direction of expansion of stone marten.

Conclusions

Our results showed that two processes, changes in species distribution boundaries and limited dispersal associated with landscape barriers, affect genetic diversity and structure in stone marten. Analysis of local barriers that reduced dispersal and large scale analyses of genetic structure and demographic history highlight the importance of isolation by distance and forest cover for the past colonization of central Europe by stone marten. This confirmed the hypothesis that human-landscape changes (deforestation) accelerated stone marten expansion, to which climate warming probably has also been contributing over the last few decades.
  相似文献   
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