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111.
Türk Çulha S Koçbaş F Gündoǧdu A Baki B Culha M Topçuoǧlu S 《Environmental monitoring and assessment》2011,183(1-4):525-529
Concentration of the some heavy metals (Co, Cu, Fe, Ni, Pb and Zn) Mediterranean mussel Mytilus galloprovincialis from Yalova (Marmara Sea) were investigated seasonally. The mean concentrations of Co, Cu, Fe, Ni, Pb and Zn in the soft tissues were 4.08 ± 0.67, 5.54 ± 0.59, 156.72 ± 20.18, 3.71 ± 1.14, 2.92 ± 0.51 and 106.23 ± 5.66 mg kg(?-1) dry weights, respectively. There were no significant differences between the metal concentrations among the seasons (P > 0.05). The mean Pb and Zn concentrations were higher than the acceptable limit proposed by International Turkish standards. 相似文献
112.
Increases in the extent and severity of spruce budworm (Choristoneura fumiferana Clem.) outbreaks over the last century are thought to be the result of changes in forest structure due to forest management. A corollary of this hypothesis is that manipulations of forest structure and composition can be used to reduce future forest vulnerability. However, to what extent historical forest management has influenced current spatial patterns of spruce budworm host species is unknown. To identify landscape-scale spatial legacies of forest management in patterns of spruce budworm host species (i.e., Abies balsamea and Picea spp.), we analyzed remotely sensed forest data from the Border Lakes landscape of northern Minnesota and northwestern Ontario. Our study area contains three regions with different management histories: (1) fine-scale logging patterns in Minnesota, (2) coarse-scale logging patterns in Ontario, and (3) very limited logging history in the Boundary Waters Canoe Area and adjacent Quetico Provincial Park. We analyzed forest basal-area data using wavelets and null models to identify: (1) at which scales forest basal area is structured, (2) where those scales of pattern are significantly present, and (3) whether regions of local significance correspond to regional boundaries that separate the study area. Results indicate that spatial patterns in host basal area are created by nonstationary processes and that these processes are further constrained by lakes and wetlands. Wavelet analysis combined with significance testing revealed a bimodal distribution of scale-specific wavelet variance and separate zones of host species basal area that partially correspond with regional boundaries, particularly between Minnesota and the Wilderness region. This research represents one of the first comparisons of forest spatial structure in this region across an international border and presents a novel method of two-dimensional wavelet analysis that can be used to identify significant scale-specific structure in spatial data. 相似文献
113.
The probabilistic approach to the evaluation of fire hazard and the effectiveness of fire-precaution measures enables a rational response to the randomness of fire outbreaks. This article employs the statistical analysis methods to elucidate the causes for the ignition of fire on a random sample of industrial buildings in the Republic of Slovenia. The analyses are based on the Structural Equation Modeling (SEM), which is a well established and important statistical analysis technique in the fields of social science, biology, psychology and medicine, but hitherto rarely applied in safety research. The results of the study demonstrate that for the analyzed random sample of industrial buildings the frequency of fire outbreaks statistically significantly depends only on the presence and the probability of exposure to the heat sources (flames, sparks, and hot surfaces), but does not significantly depend on the available quantity of flammable materials within the industrial structure. 相似文献
114.
H Vandenhove Y Thiry A Gommers F Goor J M Jossart E Holm T G?fvert J Roed A Grebenkov S Timofeyev T G?ufert 《Journal of environmental radioactivity》2001,56(1-2):157-184
When dealing with large-scale environmental contamination, as following the Chernobyl accident, changed land use such that the products of the land are radiologically acceptable and sustain an economic return from the land is a potentially sustainable remediation option. In this paper, willow short rotation coppice (SRC) is evaluated on radiological, technical and economic grounds for W. European and Belarus site conditions. Radiocaesium uptake was studied in a newly established and existing SRC. Only for light-texture soils with low soil potassium should cultivation be restricted to soils with contamination levels below 100-370 kBq m-2 given the TFs on these soils (5 x 10(-4) and 2 x 10(-3) m2 kg-1) and considering the Belarus exemption limit for firewood (740 Bq kg-1). In the case of high wood contamination levels (> 1000 Bq kg-1), power plant personnel working in the vicinity of ash conveyers should be subjected to radiation protection measures. For appropriate soil conditions, potential SRC yields are high. In Belarus, most soils are sandy with a low water retention, for which yield estimates are too low to make production profitable without irrigation. The economic viability should be thoroughly calculated for the prevailing conditions. In W. Europe, SRC production or conversion is not profitable without price incentives. For Belarus, the profitability of SRC on the production side largely depends on crop yield and price of the delivered bio-fuel. Large-scale heat conversion systems seem the most profitable and revenue may be considerable. Electricity routes are usually unprofitable. It could be concluded that energy production from SRC is potentially a radiologically and economically sustainable land use option for contaminated agricultural land. 相似文献
115.
116.
Gro Harlaug Olsen Michael L. Carroll Paul E. Renaud William G. AmbroseJr Ragni Olssøn JoLynn Carroll 《Marine Biology》2007,151(6):2167-2176
We assessed the effects of crude oil and drill cuttings on sediment oxygen demand (SOD) of marine benthic communities from
Arctic (Barents Sea) and temperate (Oslofjord) areas of the Norwegian continental shelf. Field-collected cores in both areas
were subjected to three different treatments: two concentrations of hydrocarbon-contaminated sediments, and drill cuttings
(DC). Cores were incubated for 21 days at 5°C (Barents Sea) and at 10°C (Oslofjord) during which SOD was measured five times.
We observed significantly higher SOD in the high oil concentration (HOC) and DC treatments compared to control cores from
the Arctic, but not in the temperate Oslofjord. No difference was observed between the low oil concentration (LOC) and control
at either location. The clear differences in the response of Arctic benthic communities to petroleum compounds compared to
temperate benthic communities is likely related to differences in community structure, sensitivity of individual taxa to petroleum-related
compounds and different contamination history of the two study areas. 相似文献
117.
Kalev Kuklane Ingvar Holmér 《International journal of occupational safety and ergonomics》2013,19(2):123-136
The study aimed to find out the influence of sweating on footwear insulation with a thermal foot model. Simultaneously, the influence of applied weight (35 kg), sock, and steel toe cap were studied. Water to 3 sweat glands was supplied with a pump at the rate of 10 g/hr in total. Four models of boots with steel toe caps were tested. The same models were manufactured also without steel toe. Sweating reduced footwear insulation 19–25% (30–37% in toes). During static conditions, only a minimal amount of sweat evaporated from boots. Weight affected sole insulation: Reduction depended on compressibility of sole material. The influence of steel toe varied with insulation. The method of thermal foot model appears to be a practical tool for footwear evaluation. 相似文献
118.
The purpose of this research was to shorten the composting period by speeding up the composting process and to obtain good quality compost that can be used in agriculture. In order to accomplish the acceleration of the process, different mixtures of feedstock were loaded to the composting containers to observe the effect of initial composition on the quality of the compost and the rate of composting. The first feedstock prepared was composed of grass, leaves and market waste whereas the second feedstock composed only of leaves and market wastes. Composting process was accomplished by applying different composting methods such as composting without manual stirring, with manual stirring, with aeration by air, with aeration by oxygen, with manual stirring and aeration by air and finally by with manual stirring and aeration by oxygen to achieve the purpose of the research. Aeration was found as a primary requirement for the acceleration of composting because it was observed that when the aeration was not applied the conversion of nutrients was very low. The high conversion efficiency of the nutrients in the feedstock with market and yard wastes-without grass-resulted in higher quality end product. The organic content of the composted yard and market wastes were monitored and the best operational parameters and methods were identified. Parameters such as temperature, moisture, pH and end-product metal contents were also monitored in the study. and the experiments were run in duplicates. Corrected C/N, (C/N)t/(C/N)initial, were used in the calculations which provided objectivity in comparison of the compost quality with respect to nutritional components. The C/N change was found to be higher in the container that was manually stirred and aerated with oxygen but with regard to the economic feasibility of the system aeration with air was preferred. Compost quality that was achieved in the study was compared to the standards of different countries with respect to the amount of metal contents in the end-product. The applicability of the end-product in agriculture depends on the level of contaminants in the compost, especially metals that have to be present only in trace amounts. 相似文献
119.
Result-oriented approaches to the management of drinking water catchments in agricultural landscapes
Alexander Wezel Maria Zipfer Christine Aubry Fabienne Barataud Alois Heißenhuber 《Journal of Environmental Planning and Management》2016,59(2):183-202
Management of water quality in drinking water catchments is of ongoing, high importance as nitrate concentrations are often still very high. We analysed the Augsburg catchment in Germany, a unique example where a result-oriented approach has been implemented. We investigated the historical evolution of the water protection programme, the result-oriented payment contracts with farmers, and farmer satisfaction with the contracts, based on interviews with the water utility and farmers as well as an analysis of the literature. Today, the water protection programme has been successfully implemented, and a significant reduction of nitrate concentration was achieved due to the following factors: (1) investment of non-negligible amounts of money for high compensation and remuneration payments, (2) different contract options, (3) farmers’ participation in the negotiation process for result-oriented payment contracts, (4) involvement of “outside” people and institutions in negotiation processes, (5) anticipation of starting a programme when nitrate levels were still far below legislative thresholds, and (6) a political and legislative framework allowing direct decisions by a water supplier. 相似文献
120.
An amniocentesis was performed at 13.3 weeks' gestation for advanced maternal age. A mosaic sex chromosome pattern was found: of 50 cells examined, 34 had a 45,X karyotype. In 14 cells with a modal number of 46, a recognizable Y was substituted by a small non-fluorescent marker. C-banding identified the marker as an isodicentric in 12 cells. In two cells, the non-fluorescent marker appeared to be monocentric and looked like a non-fluorescent del (Yq), but could have been an isodicentric Y with inactivation of one of the centromeres. Two cells with a modal number of 47 showed two copies of the monocentric marker. Fluorescent in situ hybridization with an alpha satellite Y-specific centromeric probe confirmed the Y-chromosome origin of the markers and allowed for more accurate prenatal diagnostic information. 相似文献