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41.
As a result of mining activities the exposure of metal sulphides to oxidation takes place with consequent release of acid mine drainage (AMD). Biomonitoring instruments have been proven to have the best deterrent effect upon polluters. A new approach in online biomonitoring, with the Multispecies Freshwater Biomonitortrade mark (MFB), was developed combining behavioural and feeding responses of the Portuguese indigenous benthic shredder, Echinogammarus meridionalis (Pinkster, 1973) (Crustacea, Amphipoda). These endpoints, along with mortality, were measured and analyzed for a gradient of sublethal doses of AMD. Original river water was used as the control and three doses of treatments were attained by adding increasing volumes of AMD to the control. The increase in AMD concentration and concomitant decrease in pH and increase in the concentration of most metals was followed by an overall increase of the mortality, decrease of locomotion/feeding activity and inhibition of the feeding rate. Mortality was observed in the two highest concentrations of AMD. Significant decrease in average locomotion/feeding activity took place in the second treatment. Although an inhibition of feeding was observed along the gradient of AMD concentration only in the highest concentration the feeding rate was significantly reduced. 相似文献
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Lázaro G. Cuinica Ilda Abreu Joaquim C. G. Esteves da Silva 《Environmental science and pollution research international》2014,21(3):2256-2262
Ostrya spp. and Carpinus spp. pollen was in vitro exposed to three atmospheric pollutants: CO, O3 and SO2. Two levels of each pollutant were used, and the first level corresponds to a concentration about the atmospheric hour-limit value acceptable for human health protection in Europe and the second level to about the triple of the first level. Experiments were done under artificial solar light with temperature and relative humidity controlled. The viability of the exposed pollen samples showed a significant decrease. Also, the germination percentage showed a significant decrease in both exposed pollens, and the effect was most pronounced for SO2, followed by O3 and CO. A general decreasing trend in the total soluble protein content of the exposed pollen samples when compared with the control was observed, but it was only statistically significant for the Ostrya spp pollen. The results showed marked effects were observed on the Ostrya spp. and Carpinus spp. pollen when exposed to air pollutant levels that can be considered safe for human health protection. 相似文献
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Assessing dam implementation impact on threatened carnivores: the case of Alqueva in SE Portugal 总被引:2,自引:0,他引:2
Santos MJ Pedroso NM Ferreira JP Matos HM Sales-Luís T Pereira I Baltazar C Grilo C Cândido AT Sousa I Santos-Reis M 《Environmental monitoring and assessment》2008,142(1-3):47-64
Large dam construction in water deficient areas is a management decision often controversial. Besides providing water storage, economical benefits, and a source of renewable energy, the construction and flooding caused by large dams cause disruptions in natural systems. We monitored the pre- and post-Alqueva dam impacts on the threatened carnivore species (polecat, otter, wildcat and Iberian lynx) populations in SE Portugal, and assessed which factors mostly contribute to post-dam distribution. Major short term impacts of large dams are: (1) increase in accessibility and human presence; (2) movement of heavy machinery and dam-workers; (3) deforestation with habitat loss and fragmentation; (4) change from lotic to lentic system; (5) lower prey availability and harsher capture; and (6) changes in land use adjacent to the reservoir. Thus, the response to those impacts can be predicted as a decline of polecat, wildcat and lynx distribution ranges, and a recovery of the otter from the severe short term impacts. Our results corroborate this hypothesis for all the species, especially during deforestation/early flooding. Otter's distribution range increased in the phase of greater impact, with a subsequent decrease with flooding. Our results suggest carnivores used "escape" areas with favourable habitat and prey conditions, however, the areas with higher probability of species presence decreased by two fold showing a drastic range reduction. To ensure populations' survival of these charismatic threatened carnivore populations of Mediterranean landscapes of south-east Portugal, we propose continuing the monitoring program and the development of a conservation program for the subsisting areas of optimal and suboptimal habitats. 相似文献
44.
Janeth Sanabria 《Journal of Agricultural and Environmental Ethics》2014,27(4):681-694
Latin American countries have an extensive biological diversity and a tropical or subtropical climate. This condition has advantages for development and for the implementation of biotechnological solutions for environmental problems. Environmental biotechnology could be used to enhance biodegradation, waste recovery, and also for the development of biotechnology-based products to diagnose and reduce environmental impacts such as biosensors, biopesticides, biofertilizers and biofuels. To generate new environmental biotechnological products, Latin American countries must not only overcome the known limitations associated with investment in science and technology and in human resource training, but also develop their own vision of using environmental biotechnology, adapted to the economic, and environmental context. Biotechnology used wisely as a tool for promoting sustainable development in Latin American countries may also contribute to the solution of problems that represent potential risks to society and the environment in general. This document discusses the context of the research and innovation in Latin American countries around environmental biotechnology and also reviews perspectives for the improvement of these developments. 相似文献
45.
Communities in Cabo Delgado have a long tradition of using medicinal plants. In Mozambique, rural populations in general are highly dependent on natural resources. One example is the use of surrounding vegetation by people from Cabo Delgado. They use plants for food, handicrafts, construction, as a primary energy source and even for medicine purposes. In this survey, we examined the diversity of plant usage for medicinal purposes by 146 individuals, including adults and youth living in the Cabo Delgado province. This community quoted 16 species of plants, belonging to 13 families. Utilisation by different categories of people based on sex and age was compared and differences were found among some groups. In general, older people show a deeper knowledge of medicinal plants than younger people. Men and women show similar knowledge of medicinal plants. 相似文献
46.
Fluorescence excitation–emission matrices (EEM) of aqueous solutions of Laurentian soil fulvic acid (LFA) at three concentrations (50, 75 and 100 mg/l) were obtained at two pH values (pH = 4.0 and 6.0) and as function of the Cu(II) ion concentration. The presence of Cu(II) ion provokes quenching of the intrinsic LFA fluorescence due to complex formation. Multivariate curve resolution (MCR-ALS) was used to successfully decompose single EEM into excitation and emission spectra for the detected components. Moreover, multidimensional (up to six dimensions) data matrices were generated by adding EEM collected as function of the LFA and Cu(II) concentrations and pH. MCR-ALS was able to resolve the excitation and emission spectra from these multidimensional data matrices given further information about the spectral variation profiles induced by the experimental factors. Conditional stability constants (log KLFACu) were calculated from the quenching profiles observed as function of the Cu(II) concentration, as well as, their trends as function of pH and LFA concentration were obtained – average (and standard deviation) of log KLFACu = 4.6 ± 0.2. This EEM/MCR-ALS methodology constitutes a new tool for the study of natural organic matter under varying experimental conditions that characterize natural environmental systems. 相似文献
47.