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101.
dentification of groups that are similar in their floristic composition and structure (habitat types) is essential for conservation and forest managers to allocate high priority areas and to designate areas for reserves, refuges, and other protected areas. In this study, the use of indigenous knowledge for the identification of habitat types in the field was compared against an ecological characterization of habitat types, including their species composition obtained by using classification and ordination techniques for a tropical landscape mosaic in a rural Mayan area of Quintana Roo, Mexico. Plant diversity data calculated from 141 sampled sites chosen randomly on a vegetation class’s thematic map obtained by multispectral satellite image classification were used for this propose. Results indicated high similarity in the categorization of vegetation types between the Mayan classification and those obtained by cluster and detrended correspondence analysis. This suggests that indigenous knowledge has a practical use and can be comparable to that obtained by using science-based methods. Finally, identification and mapping of vegetation classes (habitat types) using satellite image classification allowed us to discriminate significantly different species compositions, in such a way that they can provide a useful mechanism for interpolating diversity values over the entire landscape.  相似文献   
102.
Environmental Science and Pollution Research - The side effects from the use of plant protection products and their potential effects on non-target arthropods (NTAs) such as honey bees, other...  相似文献   
103.
Environmental Science and Pollution Research - Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality worldwide. Environmental and genetic factors are recognized as risk...  相似文献   
104.
Trace elements were determined in fish and oysters from Sepetiba Bay, Brazil, by total reflection Xray fluorescence using synchrotron radiation (SRTXRF). Cr, Mn, Fe, Ni, Cu, Zn and Se were determined in fish muscles and organs and in oyster soft tissue. SRTXRF was shown to be a good tool for the analysis of trace elements from biological tissue samples. Overall, the levels of the analysed metals were higher in oysters than in the fish samples. Metals were not uniformly distributed throughout the body of the analysed fish. The detected concentrations of Cr, Zn and Se were very high in some samples, surpassing the maximum limits established by Brazilian legislation.  相似文献   
105.
Cd, Zn, Cu, and metallothionein (MT) levels have been determined in the renal cortex and liver of 70 persons who died in Lodz and its surroundings in the years 1985–1989. The mean concentrations were: 44.9±28.6 µg Cd/g, 52.0±16.7 µg Zn/g, 2.4±1.0 µg Cu/g, 0.79±0.40 µmol Hg/g, and 3.5±1.8 µg Cd/g, 66.7±30.5 µg Zn/g, 4.9±2.1 µg Cu/g, 0.50±0.38 µmol Hg/g wet tissue in renal cortex and liver, respectively, with mean age 54.0±13.8. Smokers showed 2.4 times higher levels of Cd in the renal cortex than non-smokers. The mean body burden of Cd was 33.4±17.3 mg. Smoking increases it twofold from 22.0 mg in non-smokers to 41.8 mg in smokers.This work was supported by the grant CPBR 11.12(C-56/86) from the Institute of Rural Medicine, Lublin, Poland.Deceased.  相似文献   
106.
The evaluation of the cadmium and lead mobile forms from environmental solid samples provides information about their mobility and bioavailability. In the present study, the Cd and Pb mobile fractions were obtained by two modified extraction methods applied to industrial and acidic pH soils or to polluted sediments. In order to highlight that the extraction procedure does not significantly influence the quantitative atomic absorption spectrometric determination of cadmium and lead, the robustness of the extraction methods was evaluated and proven applying a Youden and Steiner factorial design. Within this experimental design, the shaking rate, the shaking time, and the solid/liquid extraction ratio were modified. The measurement uncertainty of the whole analytical procedure was assessed, the contribution of the factors involved in the extraction process being insignificant compared to the other uncertainty sources. The importance of the study is related to the fact that it proves the applicability in the routine laboratory practice of the modified extraction methods by increasing the extraction ratio following thorough optimization and robustness studies.  相似文献   
107.
108.
The path to sustainable small-scale fisheries (SSF) is based on multiple learning processes that must transcend generational changes. To understand young leaders from communities with sustainable SSF management practices in Mexico, we used in-depth interviews to identify their shared motivations and perceptions for accepting their fishing heritage. These possible future decision-makers act as agents of change due to their organizational and technological abilities. However, young people are currently at a crossroads. Many inherited a passion for the sea and want to improve and diversify the fishing sector, yet young leaders do not want to accept a legacy of complicated socioenvironmental conditions that can limit their futures. These future leaders are especially concerned by the uncertainty caused by climate change. If fishing and generational change are not valued in planning processes, the continuity of fisheries, the success of conservation actions, and the lifestyles of young fishers will remain uncertain.Graphical abstract Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01639-2.  相似文献   
109.
The ability of Quercus crassipes acorn shells (QCS) to remove Cr(VI) and total chromium from aqueous solutions was investigated as a function of the solution pH, ionic strength, and background electrolytes. It was found that Cr(VI) and total chromium removal by QCS depended strongly on the pH of the solution. Cr(VI) removal rate increased as the solution pH decreased. The optimum pH for total chromium removal varied depending on contact time. NaCl ionic strengths lower than 200 mM did not affect chromium removal. The presence of 20 mM monovalent cations and anions, and of divalent cations, slightly decreased the removal of Cr(VI) and total chromium by QCS; in contrast, divalent anions (SO4 2?, PO4 2?, CO3 2?) significantly affected the removal of Cr(VI) and total chromium. The biosorption kinetics of chromium ions followed the pseudo-second-order model at all solution pH levels, NaCl ionic strengths and background electrolytes tested. Results suggest that QCS may be a potential low-cost biosorbent for the removal of Cr(VI) and total chromium from aqueous solutions containing various impurities.  相似文献   
110.
Treatment of tannery wastewater is problematic due to high and variable concentrations of complex pollutants often combined with high salinity levels. Two series of horizontal subsurface flow constructed wetlands (CWs) planted with Arundo donax and Sarcocornia fruticosa were set up after a conventional biological treatment system operating at a tannery site. The aim of the CWs was polishing organics and nitrogen from the high salinity effluent (2.2-6.6?g Cl(-)?L(-1)). Both plant species established and grew well in the CW. Arundo, however, had more vigorous growth and a higher capacity to take up nutrients. The CWs were efficient in removing COD and BOD(5) with removal efficiencies varying between 51 and 80% for COD (inlet: 68-425?mg?L(-1)) and between 53 and 90% for BOD(5) (inlet: 16-220?mg?L(-1)). Mass removal rates were up to 615?kg COD ha(-1)?d(-1) and 363 BOD(5) kg?ha(-1)?d(-1). Removal efficiencies were 40-93% for total P, 31-89% for NH(4)(+) and 41-90% for Total Kjeldahl Nitrogen. CW systems planted with salt tolerant plant species are a promising solution for polishing saline secondary effluent from the tannery industry to levels fulfilling the discharge standards.  相似文献   
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