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51.
The development of conservation strategies for nontimber forest products requires the characterization of the management systems and ethnoecological knowledge of the used species, as well as the analysis of the biological impacts of these processes. This study aimed to evaluate management systems and extractivist areas and related ethnoecological knowledge of Dimorphandra gardneriana (fava d’anta) in the semiarid region of Ceará, Northeast of Brazil. Fava d’anta produces fruits with high concentration of bioflavonoids, substances with various pharmacological properties, being exploited by extractivist communities in the mosaic of protected areas in Chapada do Araripe, Ceará. Ethnoecological knowledge has been concentrated on collectors who have been in activity for a longer time and/or plant the species. We identified three management systems that can impact in different ways on fava d’anta populations, depending on the area and level of human interference with the species. The extractivists respect the zoning of protected areas and do not enter in the full protection area, choosing areas with the highest tree density. The different systems produce a mosaic that creates different extraction opportunities and modifications to the local landscape and to fava d’anta populations. Factors that may have effects on the conservation of the species are the lack of supervision and overexploitation of the resource in native areas, while the factors that affect the health of extractivists are the infrastructure of the work and exposure to wild environments.  相似文献   
52.

Purpose  

Evidence has accumulated that humic substances (HS) are not inert biogeochemicals. Rather, they cause stress symptoms and may modulate the life history of aquatic organisms. Nevertheless, it is still not clear how HS interact with additional stressors and if their effects are transgenerational. We tested the interactive effects of HS and salt to cladocerans, discussing their consequences for the persistence in fluctuating environments, such as coastal lagoons.  相似文献   
53.
The effects of the nitrofuran furaltadone on Ulva lactuca   总被引:1,自引:0,他引:1  
The use of pharmaceuticals in the food production industry as prophylatic and therapeutic agents is necessary to promote animal health, but may entail significant consequences to natural ecosystems, especially in the cases of overdosing and use of banned pharmaceuticals. The vast effects that antibiotics released into the environment have on non-target organisms are already under the scope of researchers but little attention has been given to primary producers such as macroalgae. The present study assessed furaltadone’s, an antibacterial agent illegally used for veterinary purposes, uptake capacity by Ulva lactuca and its effect in the growth of this cosmopolitan macroalgae. Differences in macroalgal growth were shown when submitted to prophylactic and therapeutic concentrations of furaltadone in the water (16 and 32 μg mL−1, respectively). The therapeutic concentration caused higher growth impairment than the prophylactic treatment did, with 87.5% and 58% reductions respectively. Furthermore, together with data collected from the accumulation assays, with values of internal concentrations as high as 18.84 μg g−1 WW, suggest that the macroalgae U. lactuca should be included in field surveys as a biomonitor for the detection of nitrofurans.  相似文献   
54.
The presence of metals in the Antarctic environment is principally a natural phenomenon caused by geochemical characteristics of the region, although some anthropogenic activities can increase these natural levels. Antarctic penguins present several of the characteristics of useful sentinels of pollution in Antarctica such as they are long-lived species situated at the top of food web. The concentrations of Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd, and Pb were determined by inductively coupled plasma–mass spectrometry in samples of liver, kidney, muscle, bone, feather, and stomach contents of gentoo, chinstrap, and Adélie penguin (12 adults, five juveniles) from carcasses of naturally dead individuals collected opportunistically in the Antarctic Peninsula area. The obtained results showed that accumulation and magnification of several elements can be occurring, so that Cd and Se reached levels potentially toxic in some specimens. The presence of human activities seems to be increasing the presence of toxic metals such as Mn, Cr, Ni, or Pb in penguins.  相似文献   
55.
In this paper, chemical and ecotoxicological data of leachates from bottom ashes collected in different Municipal Solid Waste Incinerators (MSWI) are shown. The bottom ashes were collected in Belgium (three incinerators--samples B1 to B3), France, Germany, Italy and United Kingdom (one incinerator in each country--samples F1, D1, I1 and UK1, respectively). Both chemical and ecotoxicological characterizations of leachates were done on the framework of the European Directive 91/689/EEC and the European Council Decision 94/904/EC. This work was carried out under the European project called Valomat, which was supported by the European Commission through Brite-Euram III program. Twenty-one inorganic parameters were analyzed. The ecotoxicological assays were done under standard laboratory conditions, using the bacterium Photobacterium phosphoreum, the freshwater alga Pseudokirchneriella subcapitata, the crustacean Daphnia magna and the vegetable Lactuca sativa. Chemical data varied from sample to sample. Similar results were obtained in biological assays. The samples can be classified as ecotoxic/hazardous according to the French proposal for a Criterion and Evaluation Methods of Waste Ecotoxicity (CEMWE) and the German regulation on Hazardous Waste Classification (HWC). However, samples B1, B2, B3 and D1 comply the maximum limits for direct valorization category defined in the French Classification of Bottom Ashes based on their Polluting Potential (CBAPP). Sample B1 presented the lowest level of ecotoxicity, being considered as the most interesting to be used in the development of new materials for civil engineering works.  相似文献   
56.
Aquatic macrophytes are a very important subject of study due to their capacity to restore polluted aquatic environments as they need high nutrient concentrations to develop. The present study aims to determine their temporal and physiological influence on the amount of total nitrogen, gross protein, P, Cu, Ni, Co, Cd, Pb and Cr absorbed by Eichhornia crassipes (water hyacinth) in the River Apodi/Mossoró, RN, Brazil, identifying viable possibilities for the use of cultivated biomass. Results obtained from the parameters analyzed show that these substances are impacted by the temporality and physiology of Eichhornia crassipes. Leaves showed higher crude protein and macronutrients, while the content of micronutrients and toxic elements was higher in roots. It could, therefore, be utilized to improve water quality in the River Apodi/Mossoró.  相似文献   
57.
Food and Environmental Virology - Hepatitis A virus (HAV) is the major cause of enterically transmitted infectious hepatitis. Between 2016 and 2017, the number of confirmed cases of hepatitis A...  相似文献   
58.
Surface waters located in intensive agricultural areas are more vulnerable to the pesticides contamination, which is a major concern if the water is intended to be used for human consumption. The aim of this study was to evaluate the presence and the distribution of pesticides in the Alqueva reservoir, an important source of water supply (South of Portugal), considering their representativeness in the agricultural practice of the area. For the analysis of pesticides risk impact we used the environmental quality standards in the field of water policy proposed recently by the European Commission. The pesticides belonging to the classes of phenylureas, triazines, chloroacetanilides, organophosphorous and thiocarbamates were analysed by on-line solid phase extraction-liquid chromatography-tandem mass spectrometry. The pesticides more frequently detected were atrazine, simazine, diuron and terbuthylazine. The highest levels of these pesticides were registered in spring, after pesticides treatment, namely in olive-tree and vine crops. The priority pesticides atrazine and diuron reached values above the annual average proposed in the European Union Legislation. The herbicide atrazine reached values that surpassed the proposed maximum allowable concentration (2 000 ng L? 1). The sampling stations most affected by these pesticides were Sra. Ajuda, Lucefecit and Alcarrache, located in the northern part of the reservoir, closer to Spain where the agricultural activity is more intensive.  相似文献   
59.
Platinum group metal (PGM) refining processes produce large quantities of wastewater, which is contaminated with the compounds that make up the solvents/extractants mixtures used in the process. These compounds often include solvesso, beta-hydroxyxime, amines, amides and methyl isobutyl ketone. A process to clean up PGM refinery wastewaters so that they could be re-used in the refining process would greatly contribute to continual water storage problems and to cost reduction for the industry. Based on the concept that organic compounds that are produced biologically can be destroyed biologically, the use of biological processes for the treatment of organic compounds in other types of waste stream has been favoured in recent years, owing to their low cost and environmental acceptability. This review examines the available biotechnologies and their effectiveness for treating compounds likely to be contained in precious metal extraction process wastewaters. The processes examined include: biofilters, fluidized bed reactors, trickle-bed bioreactors, bioscrubbers, two-phase partitioning bioreactors, membrane bioreactors and activated sludge. Although all processes examined showed adequate to excellent removal of organic compounds from various gaseous and fewer liquid waste streams, there was a variation in their effectiveness. Variations in performance of laboratory-scale biological processes are probably due to the inherent change in the microbial population composition due to selection pressure, environmental conditions and the time allowed for adaptation to the organic compounds. However, if these factors are disregarded, it can be established that activated sludge and membrane bioreactors are the most promising processes for use in the treatment of PGM refinery wastewaters.  相似文献   
60.
The ecological apparency hypothesis in ethnobotanical studies predicts that the apparent plants (i.e., the most easily found in the vegetation) would be the most commonly collected and used by people. To test this hypothesis, it has been used the concept of use value (VU), which measures the relative importance of useful plants for a group of people. However, the use value has got some limitations, including the fact that it does not distinguish "current use" (plants which are effectively used) from "potential use" (well known plants, however not used). Therefore, this study has tested whether the obtained results through three different use value calculations could be useful in testing the ecological apparency hypothesis. These calculations have included the current use value, the potential use value, and the general use value. It has been carried out a vegetation survey and an interview for residents from the rural communities from Barrocas and Cachoeira (Soledade, Paraíba, Brazil). It has been used Spearman's coefficient to correlate phytosociological and ethnobotanical data. It has been observed that phytosociological parameters in Cachoeira were not correlated with any of the use values calculations, except the relationship between the current use value and the relative dominance (r(s)?=?0.57; p?相似文献   
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