25 resultados para Silting
Resumo:
A região onde está inserida a área de estudo, tem sofrido explorações predatórias e má utilização do solo. Áreas antes ocupadas por cerrados, campos sujo e limpo foram substituídas pelos reflorestamentos com eucalipto, devido aos incentivos fiscais e a instalação de companhias reflorestadoras na região, pelo baixo valor das terras e baixa fertilidade do solo; mas com um grande potencial para o desenvolvimento de essências florestais. O presente trabalho visou a elaboração do Diagnóstico Físico Conservacionista da bacia do rio Capivara - Botucatu (SP), baseada no parâmetro ambiental “Coeficiente de Rugosidade”, tendo-se por unidade de estudo 10 microbacias. Os resultados obtidos com a metodologia utilizada, no estudo da bacia do rio Capivara - Botucatu (SP), para o diagnóstico físico conservacionista permitiram mostrar que o grau de deterioração físico ambiental para a bacia foi 44,34%, muito acima do limite de 10% aceitável. O alto valor do grau de deterioração, provavelmente, foi devido ao mau uso da terra que vem provocando erosões, assoreamentos de reservatórios e cursos d’águas. O parâmetro ambiental médio “coeficiente de rugosidade” para as dez microbacias do rio Capivara, permitiu classificá-las para utilização com agricultura e urbanização, pecuária e reflorestamento; ou seja, indicou que a vocação principal desta é para uso com pecuária (Classe B); as classes de declive de 0 a 12% (Classe III) e de 12 a 20% (Classe IV), respectivamente, predominaram em 62,95% e 27,00% da área total das microbacias estudadas, ocorrendo em na sua maior parte nas unidades de solo LVA (46,56%) e RQ (19,86%). A predominância de florestas, capoeiras e pastagens nas microbacias, provavelmente é reflexo da predominância de solos de baixa fertilidade. - As imagens do Sensor TM do LANDSAT 5, permitiram o mapeamento do uso da terra da bacia de maneira rápida, que segundo o índice Kappa foi de boa qualidade (0,45), além de fornecer um banco de dados para futuros planejamentos nessa área. O SIG - IDRISI permitiu constatar através de seus diferentes módulos para georreferenciamento, classificação digital do uso da terra e modelo matemático, as áreas de uso da terra com rapidez. Os parâmetros, coeficientes de forma e circularidade mostraram que as microbacias apresentam baixo perigo de enchentes devido ao seu formato, bem como, o coeficiente de rugosidade permitiu classificar as microbacias 1, 2, 3, 4 e 8 com vocação para agricultura; as 6 e 7 para pecuária; a 5 para pecuária e reflorestamento e as 9 e 10 para floresta e reflorestamento.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
The Paulista West region has suffered through the decades an intense process of deforestation when substituting native areas of Atlantic rainforest and Cerrado by agricultural cultivation, mainly coffee in the 20th century. This occupation process without planning and management of the soil resulted in serious erosion problems. Besides, the soil erosion promoted the reduction of agricultural production and the silting of rivers. This paper aims identify the factors of natural scope (geological, geomorphologic and pedologic characteristics) which participate in unleash of erosion process in two agricultural properties producers of coffee in order to apply mechanical techniques of recovery in erosive focuses of furrow and ravine kinds. One of the properties is at the city council of Getulina, located on the sandstones of Adamantina Formation; the other is at the city council of Vera Cruz, located on the sandstones of Marília Formation. However, taking into consideration the analysis of the natural dynamics, they are not enough to explain the complexity of the phenomena which are processed in the geographic space. It made indispensable the incorporation of socio-economic factors, such as the use and occupation process of the soil considering the society as landscape transformers. In order to better understand the importance of each one of the elements that contributes to the unleash of the studied erosions, it was collected soil samples in the areas, general descriptions and texture and morphologic analysis. Finally, it was elaborated the maps of the use and occupation of the soil and the vegetal coverage surrounding the properties studied. It was observed in the rural property of Getulina the substitution of the coffee by pasture that finds degraded. It, in addition to the cattle stomp, which changed the texture and density characteristics among the soil horizons, and the concentration of superficial water flow intensified the occurrence of ...
Resumo:
The crescent increasing demand of the electric power in Brazil has stimulated the implantation of Small Central Hydroelectric Power (SCHP) in several regions of the country. However, the silting up of the reservoirs is one of the main problems faced by hydroelectric power plants and SCHP. In this context, this research aimed evaluate the phenomenology and propose the enforcement of appropriate bioengineering techniques to control the intense erosive process of the hydrographical basin of the “Alto Rio Sucuriú,” that cause silting up of the reservoirs of the SCHP Costa Rica, located in the municipal district of Costa Rica (MS). In order to identify the phenomenology of the main falling in of this basin, a diagnosis of the conditions of the physical environment of the region (climate, geology, pedology, hydrology, and use of the ground) was realized. A surveying was also realized to specify the geometric feature of the falling in using the Total Station of the Ruide brand, series RTS 860R and the geodetic GPS of the Ashtech brand and the data obtained was used on the preparation of the Digital Elevation Model (DEM) of the falling in. Based on this diagnosis an official register of the falling in was done with identification of the different types of present erosion. Due to the advanced erosive stage of the falling in researched, the use of bioengineering techniques could be the best solution considering that the traditional engineering techniques make use of heavy material like concrete, iron and large machines that besides causing higher impact to the natural and esthetic aspects of the environment also require a higher investment of capital. This research establish a great cooperation to the knowledge of the erosive process and of the rehabilitation of the degraded areas with application of bioengineering techniques not only hydrographical basin of “Alto Rio Sucuriú” but also to other basins that show similar situation
Resumo:
The growing demand for electricity in Brazil has stimulated the implementation of Small Hydro Power (PCH) in various regions of the country. However, the silting of reservoirs is a major problem faced by power plants and power plants. In this context, this study aimed to evaluate the data hydrosedimentological strategic points of the watershed of the Alto Rio Sucuriú (MS) to identify the possible causes siltation of the reservoir PCH Costa Rica and suggest mitigation measures. Hydrosedimentological surveys were conducted during the rainy season (February / March 2012) and drought (August 2012), and obtained data flow, discharge liquid, suspended solids and bottom and organic matter content. Based on these results it was determined that the points 2, 4, 7 and 9 are the largest contributors to sedimentation, and point 4 got most liquid discharge (38,20 m3s-1), point 7 largest discharge of solid suspension (906,3 mg L-1), points 2 and 4 major discharges solid totals (231,59 t dia-1 and 238,185 t dia-1 respectively) and point 9 higher organic matter content (22,18%) . Found greater fraction of fine sand and very fine suspended solids and solid medium sand in the background. As mitigation measures for the process of silting of the reservoir PCH Costa Rica (MS) highlights the orientation of landowners in adopting conservation measures and planting of leguminous species native to the region in symbiosis with nitrogen-fixing bacteria
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Pós-graduação em Geociências e Meio Ambiente - IGCE
Resumo:
Pós-graduação em Geografia - FCT
Resumo:
The city of Lençóis Paulista has a great part of its agricultural land cultivated by sugar cane and reforestation of eucalyptus and pine trees. In the county there are industries that exploit energy extracted from energy cogeneration. The city of Lençóis Paulista, in recent years, has been demonstrating considerable levels of economic and social growth with the industries that are working with sugarcane and eucalyptus mainly responsible. However, the expansion of agricultural land in many cases does not take into consideration the permanent preservation areas that are protected by the law. The APP's are of fundamental importance in the management and conservation of the environment preserving the natural plants and wildlife, and also preventing erosion and the silting of drainage networks. This objective of this study was to diagnose land use, analyze if Permanent Preservation Areas are regulated to the Brazilian Forestry Code (1965) and also diagnose areas of conflict. In relation to the use and occupation of land, the research has shown how the land is divided (agricultural crops and urban zones), and highlighted areas of conflict with the Permanent Preservation Areas. All of the information is contained in maps using Geographic Information Systems. However, it has become clear that environmental laws are not respected as much in urban areas as they are in rural areas. The PPA's are virtually nonexistent, thus creating damage to the environment and local population.
Resumo:
The misuse of land by man and is causing serious problems to the environment, resulting in ecological imbalance and depletion of natural resources, especially when it comes to areas of permanent preservation, that ecosystems are essential for balance and water conservation importance . Conflicts of land use is a major cause of silting of rivers and water bodies, causing significant losses in soil and decaying natural water resources both in quantity and in quality. Within this scenario, the planning becomes essential for the control of environmental impacts to the environment factor. This study aimed to evaluate land use conflicts in permanent preservation areas of the stream Água Fria watershed, Bofete (SP) using Geographic Information System and satellite image of LANDSAT - 5 of 2010, scale 1:50000. The results show that 51.16% of the permanent preservation areas of the watershed are conflicting, especially for pasture (88.94%) and reforestation with eucalyptus (11.06%). The GIS IDRISI Selva and Cartalinx along with GIS techniques demonstrated speed and efficiency in identifying, measuring and editing maps of land use, preservation and ongoing conflicts in areas of permanent preservation.