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41.
42.
Nests of birds represent an unusual microhabitat for diverse groups of soil and epigeic invertebrates including millipedes. The millipede faunas of 301 birds nests from 63 localities throughout Slovakia were obtained by heat extraction of the nest substrates. In total 18 species of millipedes were found in 7 different types of nests of 40 bird species. The most frequent millipede species were Polyxenus lagurus and Proteroiulus fuscus. The similarities in the millipede nidifauna depending on the type of nests, ecological characteristics and geographical distribution of millipede species are discussed.  相似文献   
43.
Although contracting-out has become widespread among the OECD countries in the last couple of decades, there is limited knowledge about the arrangements chosen by urban green-space managers when contracting-out. In this paper, I take our current knowledge a step forward and present a comprehensive overview of the ‘infrastructure’ of contract designs used for contracting-out in urban green-space management. On the backdrop of a cross-national sample of a total of 14 cases from four countries, I build up a ‘toolbox’ of instruments, approaches and arrangements currently used by public clients for managing contracts with private contractors. In six major categories of instrument, I distinguish 41 specific instruments, and 15 embedded approaches for managing these instruments. Both instruments and approaches are grouped into standard and advanced kinds. Arrangements are categorized into three major types. Each type is characterized by a core combination of instruments and approaches and a limited range of variants. Finally, I explore national differences and organizational reasons supporting and directing the choice of overall contractual arrangement. For both the practitioner and the researcher, the paper can be used to inspect, compare, design and develop instruments, approaches and arrangements available in the toolbox of urban green-space management.  相似文献   
44.
The main objective of our study was to use Bayesian methods to quantify the uncertainties related to phenological development of maize (Zea mays L.) under various climate conditions. For this purpose, five different phenological methods were implemented in the dynamic crop growth model, which was subsequently optimized, using the data acquired at three different locations in Slovenia. The sensitivity analysis of the crop model was performed in order to find the set of most influential physiological parameters. Subsequent Bayesian model comparison was used in order to quantify the impact of phenological method selection on the final maize yield. The results revealed the importance of using an appropriate phenological method in order to correctly estimate the duration of the growing season and yield, when used within dynamic crop model. The limitations of the phenological methods used in this study are discussed. The selection of phenological method itself did not have a significant influence on the yield estimation, except in years with high temperatures and limiting water conditions. This raises the concern that inaccurate simulation of phenological development may increase the uncertainties of impact assessment on crop yield where crop models are fed with future climate projections.  相似文献   
45.
The aim of to the present study was to evaluate the effects of verapamil (VER) on plasma pharmacokinetics of ivermectin (IVM) and doramectin (DOR) in lactating Istrian Pramenka dairy sheep and to investigate the role of P-glycoprotein (P-gp) in transport of avermectins into milk. Pharmacokinetics of IVM and DOR following subcutaneous administration of 0.2mg/kg b.w. was evaluated in four groups of sheep. They were administered either IVM or DOR alone or in combination with verapamil (VER) at a dose of 3.0mg/kg b.w., 3 times at 12h intervals. Blood plasma and milk samples were collected at defined time intervals over 30 days post-treatment to determine IVM and DOR concentration levels. Pharmacokinetic parameters in sheep injected with IVM or DOR alone corresponded to previously published values. Comparison between sheep injected with IVM only, and sheep injected with IVM in combination with VER (IVM+VER) showed significant difference in pharmacokinetic parameters in blood plasma. Area under the concentration-time curve (AUC) truncated at 2 days (AUC(2)) was 15 and 28 μg day/L for group IVM and IVM+VER, respectively. With co-administration of VER, apparent plasma clearance (Cl/F) and mean residence time (MRT) of IVM decreased from 135 to 116 L/day and from 5.8 to 3.8 days, respectively. Similar trends were observed for DOR (AUC(2) 48 vs. 68 μg day/L, Cl/F 61 vs. 46 L/day, and MRT 5.6 vs. 4.4 days for groups DOR and DOR+VER, respectively). This study confirms that co-administration of VER has a significant effect on pharmacokinetic parameters of subcutaneously administered IVM in blood plasma. The influence on DOR pharmacokinetics is much weaker. This could be either due to the difference in lipophilicity or the difference in affinity towards P-gp as a result of structural differences. No significant influence of VER on AUC ratio of IVM and DOR between milk and plasma was observed suggesting that P-gp does not govern transport of avermectins into milk.  相似文献   
46.
During the monitoring period of alder decline phenomenon in Slovakia, indicative symptoms of Phytophthora diseases were observed in riverside stands in Slovakia. The study aimed to test the presence and diversity of Phytophthora species in declining alder stands. The samples were collected from six stands situated by rivers/streams in the central and eastern parts of Slovakia. Phytophthora plurivora and P. cactorum were detected in soil, root and water samples. The most isolated species was P. plurivora. Both Phytophthora species have been recognized in the literature as the perpetrators of black alder dieback together with other species, such as P. alni or P. polonica. To our knowledge, this is the first report of P. plurivora and P. cactorum in riverside stands with the main share of black alder in Slovakia.  相似文献   
47.
In 1998, we analysed regeneration success in four 20 year old medium-sized (600–800 m2) and four small experimental gaps (100–200 m2) in subalpine Norway spruce forest in Triglav National Park, Slovenia. We assessed the influence of site (depressions, slopes), gap size, and position within gap (centre, gap south, and north edge) on regeneration success and interactions between regeneration density, height, height increment, direct and diffuse light, ground vegetation, soil depth, thickness of humus horizons, presence of woody debris, and microrelief. Seedling density was higher in depressions, where more seedlings developed in central positions of gaps in both gap sizes, and in microsites with deeper soils, less competition from ground vegetation and convex microsites. On slopes, a higher seedling density was found in small gaps, and at the northern edge of gaps regardless of gap size. Here, seedling density was negatively influenced by diffuse radiation and positively by soil depth. The results suggest that regeneration should be initiated from medium to large gaps in depressions and small gaps on slopes. Development of established seedlings was enhanced by higher radiation levels on both sites, therefore favourable extension of the gaps would be lateral to northwards.  相似文献   
48.
Relationships between climatic factors and C, N pools in particle-size fractions of steppe soils, Russia Many soils of the Russian steppe are characterized by high soil organic matter contents and similar parent material. Thus, they are suitable for investigations of a climatic impact on C and N pools. We sampled 10 topsoils of the zonal Russian steppe at 0–10 and about 50–60 cm depth intervals. After particle-size fractionation into clay (<2 μm), silt (2–20 μm), fine sand (20–250 μm) organic C and N concentrations were determined in bulk soils and fractions. The results suggest that especially the older organic matter of the subsoil (in the silt fraction) is correlated with climatic factors. Topsoils show less evidence for climatic influences on C and N pools. As the ratio of mean annual precipitation to potential evaporation (=N/V) increases, C/N ratios decrease in all fractions and, thus, in the bulk subsoil. Obviously the degree of soil organic matter alteration was more pronounced in the order Greyzem (N/V = 1.0) > Chernozem, Phaeozem (N/V = 0.89) > Haplic Kastanozem (N/V = 0.6) > Calcic (N/V = 0.34), and Gypsic Kastanozem (N/V = 0.32). The organic carbon contents of the bulk subsoil are highest in the subsoil of the Chernozem and Phaeozem, and decrease with increasing N/V ratio (i.e., increasing heat input and dryness) to the Calcic Kastanozem. This is accompanied by an increasing enrichment of organic carbon in the silt fractions (r = ?0.99 for the correlation of the C enrichment in silt with N/V).  相似文献   
49.
This research investigated the influence of two flame retardant (FR) mixtures consisting melamine cyanurate (MeCy) and aluminum diethylphosphinate (AlPi), and MeCy and sodium aluminosilicate (SASi) at different weight ratios, on the flammability, thermal behavior and mechanical properties of polyamide 6 (PA6) composite yarns produced by meltspinning. The morphological and chemical properties of PA6/FR filaments were investigated by scanning electron microscopy and Fourier-transform infrared spectroscopy, flame retardancy by vertical burning test UL-94, thermal behavior by thermogravimetric and differential scanning calorimetric analyses, and mechanical properties by tensile tests. The results indicate that within the UL 94 V2 rating, the composite yarns differed significantly from each other in their burning and dripping behavior. The incorporation of both mixtures, MeCy+AlPi and MeCy+SASi, into the PA6/FR yarns significantly decreased the afterflame time relative to pristine PA6, confirming a lower production of flammable volatiles. This phenomenon was attributed mainly to MeCy, which caused an immediate extinguishment of the flame after the withdrawal of the igniting flame. Compared to one component MeCy, the incorporation of the MeCy+SASi mixture enhanced the thermooxidative stability of the PA6/FR yarns because of their additive effect at higher concentrations. In contrast, an antagonistic effect was obtained for the MeCy+AlPi mixture, irrespective of the concentration. Since the incorporation of MeCy+SASi did not drastically reduce the tensile properties of filaments, this mixture enables the production of the PA6/MeCy+SASi composite yarns with the enhanced flame retardancy and thermo-oxidative stability.  相似文献   
50.
European Journal of Forest Research - In the Dinaric Mountains, the future of silver fir and Norway spruce appears to be uncertain, especially given the threat of climate change to both species and...  相似文献   
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