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161.
SUMMARY

Efforts towards sustainable development are now being undertaken at all levels and the concept has increasingly entered the consciousness of the average person. For many Costa Ricans however, it is not just an abstract concept but a matter of survival as input costs increase, natural resources diminish and the soil loses fertility or is washed away. This paper reviews three case studies representing different approaches towards achieving sustainable development by different types of organization which are each innovative in preventing further destruction of tropical forest resources.  相似文献   
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The aim of this study was to investigate the similarities and dissimilarities between the pesticide samples in form of emulsifiable concentrates (EC) formulation containing chlorpyrifos as active ingredient coming from different sources (i.e., shops and wholesales) and also belonging to various series. The results obtained by the Headspace Gas Chromatography–Mass Spectrometry method and also some selected physicochemical properties of examined pesticides including pH, density, stability, active ingredient and water content in pesticides tested were compared using two chemometric methods. Applicability of simple cluster analysis and also principal component analysis of obtained data in differentiation of examined plant protection products coming from different sources was confirmed. It would be advantageous in the routine control of originality and also in the detection of counterfeit pesticides, respectively, among commercially available pesticides containing chlorpyrifos as an active ingredient.  相似文献   
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166.
Previous research has suggested that consumers are becoming increasingly concerned by the effects of conventional agricultural food production practices on human health and environmental wellbeing. This study sought to understand whether environmentally sustainable practices in the vineyard would equate to advantages in the wine marketplace. Structured questionnaires were used to ascertain the views of wine consumers in Christchurch, New Zealand. The findings of this study indicate that consumers have a strong demand for wine which is produced using “green” production practices. Consumers believe that the quality of sustainable wine will be equal to or better than conventionally produced wine, and they are prepared to pay a higher price for this wine.  相似文献   
167.

The aim of the study was to evaluate the content, occurrence, and leachability of arsenic (As), lead (Pb), and thallium (Tl) in wastes from coal cleaning processes with respect to the safe management of this waste. The study focused on wastes resulting from the wet gravitation and flotation processes employed for the purposes of coking coal cleaning in four coal mines situated in the Upper Silesian Coal Basin (Poland). The scope of the study included (i) determination of the content of these elements in the investigated wastes using atomic absorption spectrometry, (ii) evaluation of their mode of occurrence using electron microprobe analysis, and (iii) preliminary assessment of their leachability in deionized water. The content of the analyzed elements in the examined samples of coal waste was twice as high as the average content of these elements in the Earth’s crust. The contents of As and Pb, however, did not exceed their permissible contents in inert waste in accordance with Polish legal regulations based on EU directives. The limit on the content of Tl is not specified by these regulations, but its amount in the examined samples was similar to that occurring in the soils. Moreover, leaching tests have shown that these elements are hardly eluted from the analyzed material. Their content in the water leachates was generally lower than the detection limit of the analytical method, complying with the standards for good and very good water quality. Low leachability of these elements most probably results from their mode of occurrence in the investigated wastes. The chemical analysis using an electron microprobe and the analysis of the correlation between these elements, e.g., total and pyritic sulfur, have shown that Pb, As, and Tl are mainly found in sulfide minerals which are characterized by negligible solubility. In conclusion, the investigated hard coal processing waste does not constitute a threat to the environment and can be commercially used or safely neutralized, e.g., by landfilling.

  相似文献   
168.
Metals including Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, Pb, Sr and Zn were determined in muscle tissue of 12 fish species by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and cold vapour-atomic absorption spectroscopy (CV-AAS). Fish were collected from Vistula River at lower course and Dead Vistula River channel in south of Baltic Sea in Poland. The fish species examined include Round Goby (Neogobius melanostomus), Crucian Carp (Carassius carassius), Bull-rout (Myoxocephalus scorpius), Tench (Tinca tinca), Bream (Abramis brama), Burbot (Lota lot), Perch (Perca perca), Roach (Rutilus rutilus), Silver Carp (Hypophthalmichthys molitrix), Pikeperch (Stizostediun lucioperca), Brown salmon (Salmo trutta m. Trutta) and Eel (Anguilla anguilla). The median values of metal concentrations in fresh muscle tissue of 11 fish species varied as follows: Al < 0.5–60; Ba < 0.05–0.31; Ca 120–1800; Cd < 0.05–0.096; Co < 0.10; Cr < 0.10–0.50; Cu < 0.15–0.77; Fe 1.5–21; Hg 0.0058–0.65; K 1800–4200; Mg 130–560; Mn 0.12–0.59; Na 350–840; Ni < 0.2–0.31; Pb < 0.75; Sr 0.079–2.9; Zn 3.3–23 μg/g fresh weight. The Target Hazard Quotient (THQ) values calculated in this study for Cd and Hg from muscles of fish species collected from Vistula River were low in the range of 0.4 for Hg and 0.8 for Cd. Supplemental materials are available for this article. Go to the publisher's online edition of Journal of Environmental Science and Health, Part B to view the free supplemental file.  相似文献   
169.
ABSTRACT

The aim of this study was to determine the elemental composition, phenolic content and composition and antioxidant properties of Imleria badia (Fr.) Vizzini (former names Boletus badius (Fr.) Fr., and Xerocomus badius (Fr.) E.-J. Gilbert) fruiting bodies collected from sites with different levels of pollution. Imleria badia was relatively tolerant to soil contamination with toxic elements and was able to grow in As, Cd, Hg and Pb concentrations exceeding 15, 2.9, 0.4 and 77 mg kg?1, respectively. The concentration of elements in soil was reflected in the element content in I. badia. The fruiting bodies from polluted sites exhibited significantly higher content of all the analyzed elements. Among 21 individual phenolic compounds only protocatechiuc and caffeic acids, and quercetin were determined in fruiting bodies of I. badia. The differences between the concentration of the quantified phenolic compounds and the total flavonoid content in fruiting bodies of I. badia from unpolluted and polluted sites were not significant. However, the greatest total phenolic content was found in fruiting bodies from the polluted areas. The antioxidative capacity of mushrooms collected from heavily polluted sites was lower than those growing in unpolluted areas. The concentrations of some metals in soil and fruiting soil were positively correlated with phenolic content and IC50.  相似文献   
170.
The phoretic stage of Uropodina mites is a deutonymph with developed morphological adaptations for dispersal by insects. Phoretic deutonymphs are able to produce a pedicel, a stalk-like temporary attachment structure that connects the mite with the carrier. The aim of our study was to determine whether localization and density of phoretic deutonymphs on the carrier affect pedicel length. The study was conducted on a common phoretic mite—Uropoda orbicularis (Uropodina) and two aphodiid beetles—Aphodius prodromus and Aphodius distinctus. Our results show that pedicel length is influenced by the localization of deutonymphs on the body of the carrier. The longest pedicels are produced by deutonymphs attached to the upper part of elytra, whereas deutonymphs attached to femora and trochanters of the third pair of legs and the apex of elytra construct the shortest pedicels. In general, deutonymphs attached to more exposed parts of the carrier produce longer pedicels, whereas shorter pedicels are produced when deutonymphs are fixed to non-exposed parts of the carrier. A second factor influencing pedicel length is the density of attached deutonymphs. Mean pedicel length and deutonymph densities were highly correlated: higher deutonymph density leads to the formation of longer pedicels. The cause for this correlation is discussed, and we conclude that pedicel length variability can increase successful dispersal.  相似文献   
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