82 resultados para environmental changes


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Pós-graduação em História - FCLAS

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The Amazon River floodplain is an important source of atmospheric CO2 and CH4. Aquatic herbaceous vegetation (macrophytes) have been shown to contribute significantly to floodplain net primary productivity (NPP) and methane emission in the region. Their fast growth rates under both flooded and dry conditions make herbaceous vegetation the most variable element in the Amazon floodplain NPP budget, and the most susceptible to environmental changes. The present study combines multitemporal Radarsat-1 and MODIS images to monitor spatial and temporal changes in herbaceous vegetation cover in the Amazon floodplain. Radarsat-1 images were acquired from Dec/2003 to Oct/2005, and MODIS daily surface reflectance products were acquired for the two cloud-free dates closest to each Radarsat-1 acquisition. An object-based, hierarchical algorithm was developed using the temporal SAR information to discriminate Permanent Open Water (OW), Floodplain (FP) and Upland (UL) classes at Level 1, and then subdivide the FP class into Woody Vegetation (WV) and Possible Macrophytes (PM) at Level 2. At Level 3, optical and SAR information were combined to discriminate actual herbaceous cover at each date. The resulting maps had accuracies ranging from 80% to 90% for Level 1 and 2 classifications, and from 60% to 70% for Level 3 classifications, with kappa values ranging between 0.7 and 0.9 for Levels 1 and 2 and between 0.5 and 0.6 for Level 3. All study sites had noticeable variations in the extent of herbaceous cover throughout the hydrological year, with maximum areas up to four times larger than minimum areas. The proposed classification method was able to capture the spatial pattern of macrophyte growth and development in the studied area, and the multitemporal information was essential for both separating vegetation cover types and assessing monthly variation in herbaceous cover extent.

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Ensuring availability of quality water for human consumption causes becomes an increasing number of studies for the analysis of effluent before and after treatment, so that its release into receiving bodies do not cause significant changes in the river water and on the biological communities related to them. The biomarkers of toxicity have long been used to verify the potential toxic effluent and its correlation with the treatment efficiency of them. In this context, the cladoceran Ceriodaphnia dubia stands out because it is a benthic aquatic organism highly sensitive to environmental changes. In this study, to evaluate the interference of the release of treated wastewater of oil refinery in Rio Atibaia, we sought to determine the toxicity on population dynamics of Ceriodaphnia dubia microcrustacean in water samples upstream and downstream from the launch site, compared with samples from Rio Jaguarí at the point of capture by the company itself and treated effluent. We have studied the number of offspring produced in 10 replicates, each starting with a test individual of up to 24 hours for each sample and correlated the results with physical-chemical and microbiological tests performed by a laboratory technician. For most tests, the results indicate that the treated effluent gives sub-lethal toxicity to the microcrustacean, as delay the onset of the reproductive cycle of the same

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The intense urbanization in coastal environments can cause environmental changes due to the susceptibility of these areas. It is therefore of utmost importance to understand the environmental quality of coastal area and the geomorphological features are essential to make it possible, as well as the geomorphological maps that are used as an instrument to analyze the relief. However, there is no standardization among the geomorphological mapping techniques, since the proposals vary according to the taxonomy of the relief, the adopted scale and the objective of the researcher. This paper aims to carry out geomorphological mappings of sectors of the city of Mongaguá, in São Paulo state, according to the conceptions of Verstappen and Zuidam (1975) and Gustavsson, Kolstrup and Seijmonsbergen (2006), seeking to verify the possibilities and constraints that each one can provide for environmental management. Verstappen and Zuidam’s design (1975) is a classical international bibliography proposal indicating the symbols and colors that will be used to represent the relief according to the origin shape of the geomorphological features; Gustavsson, Kolstrup and Seijmonsbergen's conception (2006) is a latest international proposal which also uses symbols and colors that can be combined to represent various forms of relief, coming from different origins. The mappings in this research are although not presented as a mainstream map, but as a cartographic representation in which the symbols are superimposed on the digital ortophoto map to provide the reader an association between symbolism and the relief represented. The result is a comparative analysis among the symbols that were used in each mapping, in which is discussed what design is the most appropriate, considering the adopted scale and the geomorphological features of the mapped area

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This study aims to show some methods of environmental assets valuation. These methods are intended to assist in the economic value estimation to environmental resources by the simulation of a hypothetical market, even if there are no market prices related to them. It is about an individual preference measure against the environmental changes. Thus, the environmental valuation methods do not convert a natural resource into a market product. The present report evaluates the applicability of the valuation methods to determine the economic value for assets or resources. The challenge for all is to understand the current economic and ecologic thinking and their limitations, so as to seek improvements in the perception of natural phenomena and in the economic-oriented goal, which is the sustainable development.

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Economic activities, whether large or small, can cause a range of environmental changes, not always reversible, harming society and its quality of life. Many potentially polluting activities have already been installed in various Brazilian cities, just as at the industrial district of Rio Claro / SP, which allow the synthesis of the many environmental impacts. In this sense, this report aims to make an environmental assessment in the influence area of the industrial district of Rio Claro / SP, located in the urban area of the city. As a result, the existence of prior related studies was observed, especially the diagnosis and study of the many implications that arises from activities impacting, and further, there was a demarcation of the influence area of the district and its derivatives impacts in the influence area, the steps of prediction and mitigation measures and if these activities meet the minimum technical requirements in planning and environmental applicable legislation.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The bovine species have witnessed and played a major role in the drastic socio-economical changes that shaped our culture over the last 10,000 years. During this journey, cattle hitchhiked on human development and colonized the world, facing strong selective pressures such as dramatic environmental changes and disease challenge. Consequently, hundreds of specialized cattle breeds emerged and spread around the globe, making up a rich spectrum of genomic resources. Their DNA still carry the scars left from adapting to this wide range of conditions, and we are now empowered with data and analytical tools to track the milestones of past selection in their genomes. In this review paper, we provide a summary of the reconstructed demographic events that shaped cattle diversity, offer a critical synthesis of popular methodologies applied to the search for signatures of selection (SS) in genomic data, and give examples of recent SS studies in cattle. Then, we outline the potential and challenges of the application of SS analysis in cattle, and discuss the future directions in this field.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)