36 resultados para Remediação de solo
Resumo:
The activities developed in the coastal zone always arise the researchers interest, mainly when it is developed in fragile ecological areas, not observing the sustenable development laws. In this context, the analysis presented developed around the estuary of Curimatau river, located in the Eastern coast of Rio Grande do Norte state, integrates information provided by high resolution images of orbital remote sensing (IKONOS II, dated of July of 2003) and images of not-orbital remote sensing (Air photographs of DPU, dated of March of 1997) in a multitemporary perspective, diagnosising patterns of use and occupation, evaluating the main area´s impacts, together with the estuarian region fisiograph of Curimatau river. The use of high resolution images consequently allowed generates a precision cartography, facilitating the quantification of the evolution of the landscape and supporting decisions. Was possible yet, the definition of use areas, conservation areas and preservation areas; that were inserted in the concept of Potentialities: a fundamental element to management of vulnerable areas of the natural point of view. The information provided during the research had been stored in an Enviromental Georreferenced Data Base, constructed under the optics of Geographical Information Systems (GIS), that they facilitate the environment management Through fast access to information. The results were satisfactory, because permits the quantification of evolution of the landscape and the mapping. Beyond the geoenviromental diagnosis, was possible develop maps and matrixes that support the Rio Grande do Norte state costal Management.
Resumo:
This research aimed to analyze the forms of ownership and use of urban land in Cidade Nova, third official neighborhood of Natal (Rio Grande do Norte), between 1901 and 1929. During this period, the city and state authorities began an urban renewal, trying to transform the city, represent it as a new, modernized, able to track the progress and the new political condition of the capital of a republican state. It is observed in Cidade Nova construction of a new material and symbolic territory: the area that was once occupied by huts built by refugees of drought and some summer houses, was, from 1901, transformed, scanned through a urban plan. In Natal various municipal resolutions published between 1901-1929, showed the desires of the group leader to build on Cidade Nova neighborhood a delightful, modernized its structures to reflect the new political condition of the capital of a republican state. The analyzes of the edicts of the materials published in the newspapers A Republica and Diário do Natal, and especially the study of letters of aforamento, demonstrated how many laws were not enforced or resignified, highlighting the existing continuities. Thus, throughout the paper aims to examine how this territory was occupied and used by its inhabitants, such as the granting of land in aforamento may exemplify this practice and noncompliance and how the land was used to consolidate relations of influence and power. After all, the values given to a space, turning it into territory, resulting from the social dimension of this space, in other words, the social categories that use it. Cannot be, therefore, analyze the ways of appropriation and use of urban land in the third neighborhood of Natal without studying individuals who appropriated and used this territory. The study of the allocation of extant aforamentos of land located in this neighborhood process demonstrated the formation of a specific type of market that were at stake not only economic exchanges, but also, and above all symbolic exchanges involving political and social capital. The analysis of such personnel developed market with the lands of Cidade Nova may indicate the existing relations of power between state government, Stewardship and tenants, providing a significant example of this modernization Natal early twentieth century process, guided by a more wealthy group and influential and characterized by limited social changes
Resumo:
Statistics of environmental protection agencies show that the soil has been contaminated with problems often resulting from leaks, spills and accidents during exploration, refining, transportation and storage oil operations and its derivatives. These, gasoline noteworthy, verified by releasing, to get in touch with the groundwater, the compounds BTEX (benzene, toluene, ethylbenzene and xylenes), substances which are central nervous system depressants and causing leukemia. Among the processes used in remediation of soil and groundwater contaminated with organic pollutants, we highlight those that use hydrogen peroxide because they are characterized by the rapid generation of chemical species of high oxidation power, especially the hydroxyl radical ( OH), superoxide (O2 -) and peridroxil (HO2 ), among other reactive species that are capable of transforming or decomposing organic chemicals. The pH has a strong effect on the chemistry of hydrogen peroxide because the formation of different radicals directly depends on the pH of the medium. In this work, the materials MCM-41 and Co-MCM-41 were synthesized and used in the reaction of BTEX removal in aqueous media using H2O2. These materials were synthesized by the hydrothermal method and the techniques used to characterize were: XRD, TG/DTG, adsorption/desorption N2, TEM and X-Ray Fluorescence. The catalytic tests were for 5 h of reaction were carried out in reactors of 20 mL, which was accompanied by the decomposition of hydrogen peroxide by molecular absorption spectrophotometry in the UV-Vis, in addition to removal of organic compounds BTEX was performed as gas chromatography with detection photoionization and flame ionization and by static headspace sampler. The characterizations proved that the materials were successfully synthesized. The catalytic tests showed satisfactory results, and the reactions containing BTEX + Co-MCM-41 + H2O2 at pH = 12.0 had the highest percentages of removal for the compounds studied
Resumo:
In this work the use of coconut fiber (coir) and bamboo shafts as reinforcement of soil-cement was studied, in order to obtain an alternative material to make stakes for fences in rural properties. The main objective was to study the effect of the addition of reinforcement to the soil-cement matrix. The effect of humidity on the mechanical properties was also analyzed. The soil-cement mortar was composed by a mixture, in equal parts, of soil and river sand, 14% in weight of cement and 10 % in weight of water. As reinforcement, different combinations of (a) coconut fiber with 15 mm mean length (0,3 %, 0,6 % and 1,2 % in weight) and (b) bamboo shafts, also in crescent quantities (2, 4 and 8 shafts per specimen) were used. For each combination 6 specimens were made and these were submitted to three point flexural test after 28 days of cure. In order to evaluate the effect of humidity, 1 specimen from each of the coconut fiber reinforced combination was immersed in water 24 hours prior to flexural test. The results of the tests carried out indicated that the addition of the reinforcement affected negatively the mechanical resistance and, on the other hand, increased the tenacity and the ductility of the material.
Resumo:
The human interference in the semiarid region of Seridó Potiguar has promoted the increase of degraded areas. The economic dynamic that was established in the Seridó territory, especially after the fall of the trinomial cattle-cotton-mining in the 70s and 80s of the 20th century as pillars of the regional economy, resulted in an accelerated process of erosion of natural resources. The municipalities of the Seridó region have been spatially reordered by this new economic dynamic, marked by the growth of existing enterprises, and the development of new agricultural practices. One of the municipalities in the region that restructured its territorial space with the emergence of new agro-industrial activities was the town of Parelhas. With the demise of the trinomial cattle-cotton-mining in the 1980s, other productive activities were intensified from the 1990s, amongst them, pottery, responsible for the vegetal extraction for use as energy source. This recent economic and spatial restructuring in the region, reflected in the Parelhense municipal territory, required new productive ingredients responsible for the modification of past production relations that were based on cattle, cotton and mining. By that a process of exploring the environment was unleashed, especially the native vegetation, in an uncontrolled manner. In this context, the objective of this study was to survey and detect deforestation in the areas of Caatinga vegetation, used indiscriminately as energy supply for new agricultural practices, using remote sensing techniques based on the quantification of the Normalized Difference Vegetation Index / NDVI, Soil-Adjusted Vegetation Index / SAVI, surface temperature and rainfall data in the years 1990 and 2010. The results indicated that SAVI values above 0.2 in 1990 and 2010 represent the areas with the highest density of vegetation that occur exclusively along the major drainages in the town and areas of higher elevations. The areas between the ranges of values from 0.5 to 0.15 SAVI are areas with poor vegetation. On the other hand the highest values of temperature are distributed in the western and southeastern parts of the township, usually in places where the soil is exposed or there is sparse vegetation. The areas of bare soil decreased in extension in 2010 at 11, 6% when related to 1990, this was caused by a higher rainfall intensity in the first half of 2010, but no regeneration of vegetation occurred in some places in the western and southeastern areas of the municipality today, due to the extraction of firewood to fuel the furnaces of industries in town
Resumo:
This study was developed in the northern coast of the city of Macau, a total area of 88,52 km², located in the State of Rio Grande do Norte. It presents relatively plain surface, with interlaced of streams and gamboas, characterized by contributions of oceanic water, flooding areas of swamps. Altogether, the climatic and topographical conditions provide an ideal environment for the development of saline activity. Inserted in the geologic context of the Potiguar Basin, the region presents favorable conditions for the production of hydro-carbons. It still presents natural conditions for shrimp breeding and artisanal fishing. This work analyzes the transformations occurred in the land use, using air photographs of 1978, Landsat 5 ETM Images of 1988, 1998 and 2008. A secular analyzes was carried through the dynamics of the use of the territory and the transformations occurred in the landscape due to the increment of the productive activities. In the survey of the data for study of the area, it was verified that little alteration occurred in the 30 years. The saline activity that was present since the year of 1978 having an increase of about 5% in thirty years; the shrimp breeding activity that had its presence in the decade of 1990, presented a high growth in the land use, therefore in 1998 it presented 0.45% and currently it presents 6.59%. In the field it was observed that great areas used previously for the saline activity, today it is prepared for shrimp breeding and that the areas of petroleum exploration occupy salt mines, beaches and trays. In 1988 it presented a percentage of 0, 07% and currently it occupies 0.46%, having grown 50% in the last 10 years. Although the variation of the occupation of the area has been little expressive, shrimp breeding showed a growth of 1,200% in only 10 years. In regards to petroleum activity, there wasn t any demonstration of an increasing impact in the land use in the area of study in 26 years of exploration