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41.
Magdalena Lenda Piotr Skórka Dawid Moroń Zuzanna M. Rosin Piotr Tryjanowski 《Biological conservation》2012,148(1):180-190
Conservation biology often relies on the protection of (semi)natural habitat remnants. However, the ever increasing human population is taking over natural resources and habitats. Here, contrary to most other studies, we ask how human-associated severe changes in the environment can be used to enrich local biodiversity. We tested if industrial activity (gravel excavation) leads to the creation of habitats that support grassland butterflies and how these areas add to the richness of local species when compared to typical semi-natural habitats (grasslands). We also identified key factors affecting the richness, abundance, diversity and commonness of butterfly species to provide practical recommendations. Species richness, diversity index and the occurrence of rare species were higher in gravel-pit shores than in grasslands. The richness of butterfly species and their abundance were positively affected by the richness of plant species, shrub density and age of the gravel-pit but negatively by the cover of water reservoirs in the surrounding area and the isolation of gravel-pits from grasslands. Butterfly diversity was positively influenced by the richness of plant species and proximity of human settlement but negatively by area of the shore and isolation. Our study is the first one to show the high value of gravel-pits for the conservation of butterflies. We recommend the inclusion of gravel-pits in a system of ecological networks and management of their surroundings to improve the colonization rate of rare species. We suggests that directing interest to the possible positive effects of industrial development on biodiversity may support conservation efforts. 相似文献
42.
Purpose
Interestingly, soil is the component of the natural environment in which most hydrophobic organic pollution including polycyclic aromatic hydrocarbons (PAHs) gets accumulated. The aim of the present paper was to determine the effect of soil pollution with PAHs on the elemental composition, spectral properties, and hydrophobic and hydrophilic properties of humic acids. The research was performed on different types of soil samples that were artificially polluted with selected PAHs (anthracene, pyrene, fluorene and chrysene).Materials and methods
The soil samples were polluted with selected PAHs in an amount corresponding to 10 mg PAHs kg?1. The PAHs-polluted soil samples were incubated for 180 and 360 days at a temperature of 20–25 °C and fixed moisture (50 % of field water capacity). Humic acids (HAs) were extracted from the soil samples prior to the incubation (additionally, soils not polluted with PAHs) and after 180 and 360 days of incubation. For isolated HAs, the following analyses were performed: elemental composition, UV–Vis and IR spectra, susceptibility to oxidation, and hydrophilic (HIL) and hydrophobic (HOB) properties were determined using high-performance liquid chromatography.Results and discussion
The research demonstrated that introducing anthracene, fluorene, pyrene and chrysene to soil samples resulted in a change in some of the quality parameters of humic acids. However, the intensity and the direction of those changes were determined by soil properties. The changes of the parameters, once PAHs were introduced, that did not depend on the soil properties were ΔA 665u and ΔA 465u (susceptibility to oxidation at wavelengths of 465 and 665 nm) as well as HIL/ΣHOB. The same tendency in changes in the structure of humic acids, once PAHs were introduced, was also observed based on the Fourier transform infrared spectra pattern.Conclusions
A single pollution of soils with PAHs that leads to changes in the quality parameters of humic acids shows that, as for the soils permanently exposed to pollution with those compounds, significant changes can occur in the properties of humic acids. As a result, it can lead to a change in the functions played by humic acids in the environment. 相似文献43.
The aim of the study was to determine the situation of equine arteritis virus (EAV) infections in hucul horses. A total of 176 horses (154 mares and 22 stallions) from the biggest hucul horse stud in Poland were tested. Antibodies against EAV were detected in 97 (55.1%) horses. The EAV seroprevalence among mares was 53.2% while in stallions - 68.2%. The percentage of positive mares increased with their age, thus amongst the mares of less than 2 years of age the percentage was 32.5%, while in the group of 3-5 years old increased to 59.4% and in the mares in the age of 6-10 years and older than 10 years 89.5% and 95% were seropositive, respectively. Among 11 seropositive stallions five were supposed to be shedders of EAV with their semen. It is likely that those persistently infected stallions were the reservoirs of the virus in the stud. Genetic studies using of ORF5 gene showed high homology between the viruses detected in the semen of those stallions what suggested lateral transmission between the stallions sharing the same stable. Persistent infection in an immature stallion, which has not yet been used for breeding, was established as a result of infection via respiratory route. Phylogenetic analysis confirmed that all hucul viruses shared the same ancestor and as most of EAV strains dominating in Polish horse population belonged to the European origin EAV subgroup (EU-1). 相似文献
44.
This paper presents the influence of selected methodological aspects on the results of particle‐size distribution (PSD) as measured by the laser diffraction method (LDM). The investigations were carried out using the Mastersizer 2000 with Hydro MU attachment (Malvern Ltd., UK). It was found that for the investigated soils: (1) optimal speed of pump and stirrer was 2500 rpm, (2) optimal measurement time was ≈ 1 min, (3) there are two, practically equivalent methods for soil‐sample dispersion: chemical (with the use of a solution of sodium hexametaphosphate) or physical (by means of ultrasound application for 4 min at a maximum power of 35W), (4) one must not use the chemical and physical dispersing methods simultaneously, because this can lead to aggregation (not dispersion) of soil particles, (5) the Fraunhofer theory (physical models) can be used to convert scattered‐light data to PSD. In the case of the Mie theory, the best results were obtained for a refractive index (RI) in the range of 1.5–1.6 and an absorption index (AI) of 1.0. It was also found that most of the discussed parameters depend on design of the measuring device and on the type and volume of the investigated suspensions. It is necessary, therefore, to explain how the data was obtained every time and to specify the details in the methodological part of the paper. 相似文献
45.
Journal of Soils and Sediments - The relics of the industry are widely used for educational and touristic purposes. There are many examples of brownfield sites turned into tourist attractions.... 相似文献
46.
Application of image analysis for the varietal classification of barley:: Morphological features 总被引:1,自引:0,他引:1
This paper presents an exploratory investigation of the application of morphological features in image analysis for varietal classification of Polish spring barley. The objective of this study was to determine the utility of morphological features for classifying individual kernels of five varieties of barley. Furthermore, this study was performed to find the best method to classify kernels of barley with the lowest error of classification. Image processing consisted of several steps: image acquisition, segmentation, external and internal image feature extraction, classification and interpretation. Each barley kernel was described using 74 morphological features. The selection was carried out using three methods based on: Fisher's coefficient, probability of error and average correlation coefficient and mutual information. Principle component analysis (PCA), linear discriminant analysis (LDA), and non-linear discriminant analysis (NDA) were used throughout this paper as the classification methods. The results confirmed that the method using morphological features may be successfully employed in image analysis for preliminary varietal identification of barley kernels. Furthermore, LDA was found to be the method which best separated different varieties of objects. 相似文献
47.
Production of transgenic adult plants from clementine mandarin by enhancing cell competence for transformation and regeneration 总被引:3,自引:0,他引:3
Genetic transformation of mature trees is difficult because adult tissues are recalcitrant to Agrobacterium tumefaciens infection and transformation and because transgenic mature events are less competent for regeneration. We have shown that reinvigoration allows manipulation of the vegetative phase to increase the potential for transformation and regeneration without loss of competence for flowering and fruiting. To produce transgenic plants from clementine mandarin (Citrus clementina hort. ex Tanaka), we optimized the conditions of the source material both ex vitro and in vitro. Grafting of mature buds on juvenile rootstocks in the spring and preventing multiple bud sprouting by removing all but one bud permitted selection of vigorous first flushes for in vitro culture. Use of additional virulence genes from A. tumefaciens to increase transformation frequency and optimization of culture media and conditions to enhance explant cell competence for T-DNA integration and organogenesis resulted in efficient and reliable transgenic plant production. Transformed regenerants from explants, cultured in media without antibiotics, were identified by a screenable marker (either beta-glucuronidase or green fluorescent protein (GFP)), creating the possibility of generating transgenic clementine plants without antibiotic resistance marker genes. Stable integration of foreign genes was demonstrated by Southern blot analysis, and expression of these foreign genes was confirmed by detection of GFP fluorescence in leaves, floral organs and fruits of the transgenic plants. 相似文献
48.
Agnieszka POMORSKA-ZNISZCZYSKA Marcin SZCZEPANIK Nikola ADAMCZYK Magdalena TARACH 《Journal of Equine Science》2022,33(3):37
Videodermoscopy is a method that enables the examination of many parameters of the skin and its structures. The aim of this study was to assess specific dermoscopic parameters in purebred Arabian horses during the summer. The study involved 21 clinically healthy purebred Arabian horses (18 mares and three stallions) that had not been used for breeding and were 1 to 25 years old. The videoderoscopic evaluation was performed on seven selected areas of the body: forehead, mane, neck, chest, flank, rump, and tail. The tests were carried out with Vidix and Olympus cellSens specialised software. Videodermoscopy revealed that the skin was pigmented in all of the bay horses, in one of the seal brown horses, and in the 10 grey horses. Only one grey horse and one chestnut horse had unpigmented skin. Hair thickness ranged from 44.82 µm (neck) to 75 µm (mane). Regarding the amount of hair in the field of view, the highest and lowest numbers of hairs were found on the neck (3,004) and mane (990), respectively. A valuable insight obtained from our research is that it is possible to use digital image analysis for precise quantitative and qualitative evaluations of the skin and its structures. 相似文献
49.
Magdalena Zielinska Piotr Zapotoczny Ireneusz Białobrzewski Krystyna Zuk-Golaszewska Marek Markowski 《Industrial Crops and Products》2012,37(1):69-75
Selected engineering properties of seeds of four red clover varieties were studied. The seeds of diploid and tetraploid forms were statistically different in terms of true and bulk density, porosity, volume, 1000 seed weight, equivalent diameter and yellowness index. The volume, 1000 seed weight and equivalent diameter were found to be statistically higher for tetraploid than for diploid forms. The accuracy of varietal classification based on the physical properties of seeds was found to be most satisfactory. Varieties of Bona and Jubilatka were identified with 100% accuracy based on the physical properties of seeds. Bona was the most conducive variety for the classification of red clover seeds based on four groups of engineering properties. The relationships between groups of properties described by total redundancy did not exceed 50% for any of variable pairs. 相似文献
50.
Villar-Salvador P Planelles R Oliet J Peñuelas-Rubira JL Jacobs DF González M 《Tree physiology》2004,24(10):1147-1155
Drought stress is the main cause of mortality of holm oak (Quercus ilex L.) seedlings in forest plantations. We therefore assessed if drought hardening, applied in the nursery at the end of the growing season, enhanced the drought tolerance and transplanting performance of holm oak seedlings. Seedlings were subjected to three drought hardening intensities (low, moderate and severe) for 2.5 and 3.5 months, and compared with control seedlings. At the end of the hardening period, water relations, gas exchange and morphological attributes were determined, and survival and growth under mesic and xeric transplanting conditions were assessed. Drought hardening increased drought tolerance primarily by affecting physiological traits, with no effect on shoot/root ratio or specific leaf mass. Drought hardening reduced osmotic potential at saturation and at the turgor loss point, stomatal conductance, residual transpiration (RT) and new root growth capacity (RGC), but enhanced cell membrane stability. Among treated seedlings, the largest response occurred in seedlings subjected to moderate hardening. Severe hardening reduced shoot soluble sugar concentration and increased shoot starch concentration. Increasing the duration of hardening had no effect on water relations but reduced shoot mineral and starch concentrations. Variation in cell membrane stability, RT and RGC were negatively related to osmotic adjustment. Despite differences in drought tolerance, no differences in mortality and relative growth rate were observed between hardening treatments when the seedlings were transplanted under either mesic or xeric conditions. 相似文献