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231.
There is a need to evaluate the interference of pig slurry rate and the terrain slope in the chemical elements losses from the soil. This work aimed to quantify water and chemical element losses by surface runoff due to terrain slope and pig slurry rate (PS) in two soils with contrasting textures. Two trials were evaluated in 2018 and 2019 in Cambisol and Nitisol. Rates of 0, 22.5, 45, and 90 m3 ha−1 yr−1 of PS were applied superficially in sites with slopes ranging from 10% to 35%. Perennial forage grass Tifton 85 (Cynodon dactylon) was grown as summer crop and ryegrass (Lolium multiflorum) was sown in the cold seasons in a field environment. Were determined the runoff, the volume of water, and chemical elements (Al, Ca, P, Mg, Cd, Cr, Cu, Mn, Fe, Pb, and Zn) lost by the surface runoff after natural rainfall. Increasing land slope elevated water losses substantially, on average 23.4 times in Cambisol and 10.8 times in Nitisol. This increase resulted in average increases of 27.6 and 12.4 times in the losses of the chemical elements analyzed for Cambisol and Nitisol, respectively. There was a reduction in water losses by surface runoff due to increased PS rates applied in both sites. The increased PS rate affected the losses of Cr and Cu in Cambisol and P, Mg, Cd, and Cu in Nitisol. The clayey soil potentiated the water and chemical elements losses by surface runoff in relation to the soil with lower clay content. Regardless of the soil, water and chemical element losses are maximized at higher slopes.  相似文献   
232.
This study presents an evaluation of the extent of differences between measurements performed by O(3) and NO(2) diffusive samplers and by the reference methods for diffusive samplers commercially available. The tests were performed in an exposure chamber under extreme conditions of controlling factors and under field conditions. For NO(2), the results of the laboratory experiments showed that most of the diffusive samplers were affected by extreme exposure conditions. The agreement between the samplers and the reference method was better for the field tests than for the laboratory ones. The estimate of the uptake rate for the exposure conditions using a model equation improved the agreement between the diffusive samplers and the reference methods. The agreement between O(3) measured by the diffusive samplers and by the reference method was satisfactory for 1-week exposure. For 8-hour exposures, the diffusive samplers with high uptake rates quantified better the O(3) concentration than the samplers with low uptake rates. As for NO(2), the results of the O(3) field tests were in better agreement with the reference method than the ones of the laboratory tests. The field tests showed that the majority of diffusive samplers fulfils the 25% uncertainty requirement of the NO(2) European Directive and the 30% uncertainty requirement of the O(3) European Directive for 1-week exposure.  相似文献   
233.
Journal of Material Cycles and Waste Management - Sewage sludge (SS) is a residue resulting from wastewater treatment, which is widely increasing due to population growth and economic development....  相似文献   
234.
Lead (Pb) has been highlighted as a major pollutant of both terrestrial and aquatic ecosystems, causing negative impacts to these environments. The concentration of Pb in plants has increased in recent decades, mainly due to anthropogenic activities. This study has as a hypothesis that the species Oxycaryum cubense (Poep. & Kunth) Palla, abundant in aquatic environments, has the potential to be used a phytoremediator. The plants were grown in a hydroponic system with Pb in increasing concentrations (0, 4, 8, 16 and 32 mg l?1) for 15 days. Inductively coupled mass spectrometer (ICP OES) was used to determine the concentration of mineral nutrients and lead. Optical and transmission electron microscopy were used for the analysis of cellular damage induced by lead in roots and leaves. Ultrastructural alterations were observed as disorganization of thylakoids in the chloroplast and disruption of mitochondrial membranes in cells of leaf tissues of plants subjected to increasing Pb concentrations. There was accumulation of Pb, especially in the root system, affecting the absorption and translocation of some mineral nutrients analysed. In roots, there was reduction in the thickness of the epidermis in plants treated with Pb. This species was shown to be tolerant to the Pb concentrations evaluated, compartmentalizing and accumulating Pb mainly in roots. Due to these results, it may be considered a species with phytoremediation capacity for Pb, with potential rizofiltration of this metallic element in contaminated watersheds.  相似文献   
235.
We determined the length, volume, dry biomass, and density in seeds of five castor bean cultivars and verified notable physicochemical trait differences. Seeds were then subjected to different toxic aluminum (Al) concentrations to evaluate germination, relative root elongation, and the role of root apices’ rhizosphere mucilage layer. Seeds’ physicochemical traits were associated with Al toxicity responses, and the absence of Al in cotyledons near to the embryo was revealed by Al-hematoxylin staining, indicating that Al did not induce significant germination reduction rates between cultivars. However, in the more sensitive cultivar, Al was found around the embryo, contributing to subsequent growth inhibition. After this, to investigate the role of mucilage in Al tolerance, an assay was conducted using NH4Cl to remove root mucilage before or after exposure to different Al concentrations. Sequentially, the roots were stained with hematoxylin and a quantitative analysis of staining intensity was obtained. These results revealed the significant contribution of the mucilage layer to Al toxicity responses in castor bean seedlings. Root growth elongation under Al toxicity confirmed the role of the mucilage layer, which jointly indicated the differential Al tolerance between cultivars and an efficient Al-exclusion mechanism in the tolerant cultivar.  相似文献   
236.
Ozone (O3) is a toxic secondary pollutant able to cause an intense oxidative stress that induces visual symptoms on sensitive plant species. Controlled fumigation experiment was conducted with the aim to verify the O3 sensibility of three tropical species: Piptadenia gonoachanta (Mart.) Macbr. (Fabaceae), Astronium graveolens Jacq. (Anacardiaceae), and Croton floribundus Spreng. (Euphorbiaceae). The microscopical features involved in the oxidative stress were recognized based on specific histochemical analysis. The three species showed visual symptoms, characterized as necrosis and stippling between the veins, mostly visible on the adaxial leaf surface. All the studied species presented hypersensitive-like response (HR-like), and peroxide hydrogen accumulation (H2O2) followed by cell death and proanthocyanidin oxidation in P. gonoachanta and A. graveolens. In P. gonoachanta, a decrease in chlorophyll autofluorescence occurred on symptomatic tissues, and in A. graveolens and C. floribundus, a polyphenol compound accumulation occurred. The responses of Brazilian native species were similar to those described for sensitive species from temperate climate, and microscopical markers may be useful for the detection of ozone symptoms in future studies in the field.  相似文献   
237.
Arunachal Pradesh in northeastern India is considered a biocultural diversity hotspot, with diverse tribal peoples and immense floral and faunal diversity. This rich diversity, sustained through the morang (community forests) and jhum (slash and burn) cultivation systems, is the backbone of native communities’ livelihood security. Kebung (Ratufa bicolor) and other squirrel species are intricately related to biocultural systems of the Adi people of Arunachal Pradesh. Primary surveys and participatory rural appraisals were carried out in 20 villages of East Siang and Upper Siang districts of the state. Results indicated that Kebung squirrels are hunted from successional forests, including from morang and jhum lands. They are an integral part of the Adi sociocultural, economic and livelihood systems, being used for food, medicinal, ceremonial and other purposes. Hunting methods vary in the traditional and transitional Adi villages. Recently, kebung populations have diminished, and this is attributed to overhunting. In particular, a decrease in kebung populations in some morang and jhum habitats has threatened the biocultural resources of the Adi. Knowledge and management practices relating to kebung hunting are gradually eroding among the younger Adi generations. However, the community recently passed a resolution for kebung conservation, supported by the customary norms. We conclude with a discussion of policy requirements for sustainable management of kebung populations to maintain Adi biocultural and livelihood security.  相似文献   
238.
Environmental Science and Pollution Research - This study provides an analysis of the spatial distribution and trends of NO, NO2 and O3 concentrations in Portugal between 1995 and 2010....  相似文献   
239.
This study presents information on the use of medicinal animals in a semiarid area of northeast Brazil, a region where animals have recognized importance in local popular medicine. The information on the use of animals for medicinal purposes was obtained through semi-structured questionnaires, complemented by free interviews and informal conversations. The results obtained showed that the residents of the area studied utilize a considerable richness of animal species (n = 42) for medicinal purposes, as occurs in other areas of Brazil’s semiarid region, demonstrating that zootherapy represents an alternative form of health care that is important to the inhabitants of the region. There is a need for new investigations on medicinal fauna, aimed at promoting the sustainable use of eventual medicinal species and preserving popular knowledge associated with the use of animal species.  相似文献   
240.
Renewable energy is often associated with the production of clean electricity and free of significant adverse impacts. However, several studies have been highlighting the importance of the assessment of social impacts of these technologies, including not only the benefits but also the potential negative aspects most frequently affecting local population. The energy matrix in Brazil is already built up on a renewable system largely supported on hydropower but other technologies with special emphasis on wind power start to have a major role, with a strong growth forecasted for this sector in the coming years. This article discusses the integration of solar and wind power in the Brazilian electricity system focusing on the social awareness and acceptance for the population living in high potential regions. For this, a questionnaire was proposed with the aim of evaluating the level of knowledge of wind and solar power, their social acceptance and perceptions towards cost, local development and environmental impacts. The questionnaire was implemented in an academic institution in the State of Rio Grande do Norte (RN) including students and professors as key actors for the present and future energy policy decision making. The implementation process and the obtained results are described allowing to conclude on the high level of acceptance of solar and wind power in the country and the region, with low evidence of not in my backyard syndrome.  相似文献   
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