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Efici?ncia da recupera??o ambiental de ?reas antropizadas pela minera??o de ferro do Complexo Caraj?s - PA / Efficiency of environmental rehabilitation of areas disturbed by mining iron Complex Caraj?s - PAGON?ALVES, Fernando Soares 16 April 2012 (has links)
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Previous issue date: 2012-04-16 / CAPES / Mining activities have a direct influence on economic development, which directly affects the gross domestic product (GDP), mainly in developing countries. The environmental interference provided by the mining activities can vary in intensity according to the mineral exploited, but they are always punctual activities. This study was conducted in the mineral province of Caraj?s, PA, in areas revegetated post mining iron ore, and to evaluate the processes of vegetation arising from revegetation of barren slopes, starting from the initial hypothesis that signed the revegetation of slopes of waste in the mining of iron using cocktails of seed species in the rainforest and savanna Metal?fila can act as facilitators of natural succession and conditioners as the substrate. The second hypothesis is that signed the removal, storage and return of surface soil organic horizon ("topsoil") after the operation by open pit mines have an essential role in the revegetation process, because they already provide quantitative and qualitative characteristics that reflect the communities previously existing in the area. In this work were highlighted four areas of study, three areas undergoing revegetation and an area with the presence of primary forest. The variables analyzed were phytosociology, photosynthetically active radiation, chemical quality of the stock of litter, soil fauna and soil fertility. The results indicate that the revegetation processes used, promoted the formation of a plant community which facilitates the process of succession over time, as many of the species used in the cocktail of seeds of the CCI and workshop areas are being replaced by species more adapted to conditions of each site. In the area called Hoppe, the herbaceous species that colonized the area are being replaced by shrub and tree species. The quality of the provided information able to litter cluster areas of studies according to the nutrients present in the litter, the areas being divided into Workshop CCI and the concentrations of lignin, cellulose, P and Mg, while areas were grouped Hoppe and Mata as a function of P and N fractions present in the twigs and leaf litter. But the use of soil fauna indicated that the groups Collembola and Formicidae will be extremely important for monitoring the quality of sites over time. From these results it was concluded that the use of biotic and abiotic indicators in studies of recovery of mined areas should be thoroughly studied and documented, they offer attributes able to understand developments in the recovery process. / As atividades de minera??o t?m influencia direta sobre o desenvolvimento econ?mico, afetando diretamente o produto interno bruto (PIB), principalmente dos pa?ses em desenvolvimento. As interfer?ncias ambientais proporcionadas pelas atividades de minera??o podem variar de intensidade de acordo com o mineral explorado, mas sempre s?o atividades pontuais. O presente estudo foi realizado na prov?ncia mineral de Caraj?s-PA, em ?reas revegetadas p?s minera??o de min?rio de ferro, tendo como objetivo avaliar a forma??o vegetal oriunda dos processos de revegeta??o de taludes de est?ril, partindo da primeira hip?tese firmada que a revegeta??o dos taludes de est?ril em ?rea de minera??o de ferro utilizando coquet?is de sementes de esp?cies pertencentes a savana metal?fila e floresta ombr?fila podem agir como facilitadores da sucess?o natural e como condicionadores do substrato. A segunda hip?tese firmada ? que a retirada, armazenamento e retorno do horizonte org?nico superficial do solo (?topsoil?) ap?s a explora??o por minera??es a c?u aberto t?m fundamental papel no processo de revegeta??o, por j? apresentar caracter?sticas quantitativas e qualitativas que refletem as comunidades anteriormente existentes na ?rea. Neste trabalho foram demarcadas quatro ?reas de estudo, sendo tr?s ?reas em processo de revegeta??o e uma ?rea com presen?a de mata prim?ria. As vari?veis analisadas foram fitossociologia, radia??o fotossinteticamente ativa, qualidade qu?mica do estoque de serrapilheira, fauna do solo e fertilidade do solo. Os resultados obtidos apontam que os processos de revegeta??o utilizados, promoveram a forma??o de uma comunidade vegetal que viabilize o processo sucessional ao longo do tempo, pois muitas das esp?cies utilizadas no coquetel de sementes das ?reas CCI e Oficina est?o sendo substitu?das por esp?cies mais adaptadas ?s condi??es de cada s?tio. Na ?rea denominada Hoppe, as esp?cies herb?ceas que colonizaram a ?rea est?o sendo substitu?das por esp?cies arbustivas e arb?reas. A qualidade da serrapilheira forneceu subs?dios capazes de agrupar as ?reas de estudos em fun??o dos nutrientes presentes na serrapilheira, sendo as ?reas CCI e Oficina agrupadas em fun??o das concentra??es de lignina, celulose, P e Mg, enquanto que as ?reas Hoppe e Mata ficaram agrupadas em fun??o do Ca e N presente nas fra??es galhos e folhas da serrapilheira. J? a utiliza??o da fauna do solo indicou que os grupos Collembola e Formicidae ser?o de extrema import?ncia para o acompanhamento da qualidade dos s?tios ao longo do tempo. A partir destes resultados foi poss?vel concluir que a utiliza??o de indicadores bi?ticos e abi?ticos em estudos de recupera??o de ?reas mineradas devem ser amplamente estudados e documentados, pois oferecem atributos capazes de compreender a evolu??o nos processos de recupera??o.
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Restoration of a Rich Fen by Top Soil Removal : Temporal and Spatial Responses among Vascular Plants, Bryophytes and Land Snails during 15 yearsEvasdotter, Liselott January 2011 (has links)
Rich fens are calcareous and nutrient poor wetlands with a rich flora of orchids, sedges and mosses. As many as one hundred plant species are rich fen specialists. Many wetlands have been drained historically, and transformed to agricultural land or production forests. Today rich fens cover only 2-3% of the total mire area in Sweden. Rich fen is a rare and valuable habitat also from a European perspective and is protected in the Natura 2000-network. To increase and maintain the biodiversity and ecosystem services rich fens can offer, it is important to increase the rich fen area by restoration and management. Rich fen restoration can be carried out in different ways. In this report the restoration method of top soil removal is investigated. The method has never been tested before in Sweden and therefore it is important to evaluate the suitability of the method for further conservation work. Before restoration, the study area had been drained, used as arable land and pasture, and finally become abandoned and overgrown by tall eutrophic herbaceous vegetation. An excavator dug away the layer of nutrient rich top soil and then the site was left for spontaneous development. Adjacent to the restored area, there is a small remnant of rich fen. Monitoring of the restored area was performed during the first five years after the restoration. I repeated the monitoring after ten years, and analyzed the long-term succession of plants and snails, in comparison with the status in the reference fen. The vegetation in the restored parts is approaching the one in the reference fen. For example, the number of rich fen specialists has increased steadily. However, the colonization of bryophytes is slow. They cover at most 20 % in the restored parts, while 80 % in the reference fen, possibly because of dispersal limitation and the fact that the restored area is drier than the reference fen. More species of herbs can be found in the restored parts than in the reference fen. Another difference is the high cover of bare soil in the restored areas, compared to none in the reference fen. Some trees and bushes are growing in the area, primarily birch (Betula pubescens) and different species of Salix. The land snails have successfully colonized the restored areas. After two years the same number of species was found in the restored area, as in the reference fen. The total number of species found in the restored areas was 26, compared to 29 in the reference fen, among them three rare rich fen indicator species. The results show how the restored site has developed from bare mineral soil to a rich fen site, approaching the species composition of the reference fen. Several species of rich fen specialists among vascular plants, bryophytes and land snails have established in the restored areas. The small rich fen close to the restored area functions as a source from where plants and animals can spread. Overall the restoration shows very positive results, going from bare soil to rich fen vegetation in only ten years.
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Uso da camada superficial de solo na revegetação do estéril de extração de granito / Use of soil surface layers in revegetation of waste-rock piles from granite miningAlmeida, Alexandre D'ávila de 24 February 2006 (has links)
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Previous issue date: 2006-02-24 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The present study evaluated the efficacy of using a soil surface layer (topsoil) to cover deposits of waste-rock piles from granite extraction in order to enable the substratum to establish a plant community. With this objective, a greenhouse experiment was conducted with seven treatments (waste-rock, waste-rock + 5.0 cm topsoil, waste-rock + 10,0 cm topsoil, waste-rock + 20.0 cm topsoil, waste-rock + 10.0 cm B horizon, waste-rock + 4 L of incorporated manure, and waste-rock + 10.0 cm topsoil stored in the previous year). The experimental units consisted of a pot holding 32 dm3 substratum where one Joannesia princeps Vell. seedling was planted as indicator plant. The experiment was monitored over the course of 120 days. In the end of this period the indicator plants were evaluated biometrically, and the dry matter of the spontaneously germinated vegetation in each pot was analyzed. Substratum samples from each pot were also collected for analyses of microbiological aspects (CBM and qMic), of total organic carbon (COT) and of total nitrogen (NT). The results did not show any significant difference between thicknesses of 5, 10 or 20 cm, or even when no topsoil at all was used, regarding the establishment of an initial community of herbaceous plants by means of spontaneous germination. Topsoil (10 cm) addition proved effective, however, to establish tree vegetation, resulting in a significant growth increment of Joannesia princeps Vell. In both situations, the treatment of incorporated manure (4 L) resulted in strongest plant growth. No positive effect was verified by the substitution of topsoil by an equally thick layer of material derived from the soil B horizon. In the case of previously stored topsoil, no quality reduction was verified after a storage time of 12 months. The chemical and microbiological analyses were not able to detect significant alterations in the microbiota of the waste-rock substratum samples, but evidenced a tendency of increased COT and NT contents of the samples with the increasing thickness of the topsoil layers. / O presente trabalho teve por objetivo avaliar a eficiência de utilização da camada superficial do solo (topsoil) como cobertura de depósitos de estéril da extração de granito de modo a proporcionar a este substrato condições para o estabelecimento de uma comunidade vegetal. Para tanto, foi executado um experimento em casa de vegetação com sete tratamentos (estéril, estéril + 5,0 cm topsoil, estéril + 10,0 cm topsoil, estéril + 20,0 cm topsoil, estéril + 10,0 cm horizonte B, estéril + 4 L de esterco de curral incorporado e estéril + 10,0 cm topsoil armazenado no ano anterior). As unidades experimentais foram constituídas por um vaso com capacidade de 32 dm3 de substrato onde foi realizado o plantio de uma muda de Joannesia princeps Vell. como planta indicadora. O experimento foi acompanhado durante 120 dias. Ao fim deste período foram realizadas as avaliações biométricas das plantas indicadoras, bem como análise da matéria seca da vegetação germinada espontaneamente em cada vaso. Também foram coletadas amostras do substrato de cada vaso para análises microbiológicas (CBM e qMic), de carbono orgânico total (COT) e de nitrogênio total (NT). Os resultados não evidenciaram diferença significativa entre as espessuras de 5, 10 e 20 cm, ou mesmo ao não uso do opsoil, para o estabelecimento de uma comunidade inicial de herbáceas através da germinação espontânea. A adição do topsoil (10 cm) mostrou-se eficiente, porém, na etapa de estabelecimento da vegetação arbórea, ao propiciar um incremento significativo no crescimento de Joannesia princeps Vell. Em ambas as situações, a incorporação de esterco de curral (4 L) foi o tratamento que acarretou maior crescimento das plantas. Não foi verificado efeito positivo na substituição do topsoil por camada de igual espessura formada por material oriundo do horizonte B do solo. Quanto à utilização de topsoil já armazenado anteriormente, não foi comprovada diminuição de sua qualidade para o tempo do armazenamento de 12 meses. As análises químicas e microbiológicas utilizadas não foram capazes de detectar significativas alterações na microbiota das amostras do substrato estéril, porém evidenciaram uma tendência de aumento dos teores de COT e NT das amostras ao aumento da espessura da camada de Topsoil.
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Tree species diversity, topsoil conditions and arbuscular mycorrhizal association in the Sidama traditional agroforestry land use, southern Ethiopia /Zebene Asfaw. January 2003 (has links)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.
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A hydrologic assessment of using low impact development to mitigate the impacts of climate change in Victoria, BC, CanadaJensen, Christopher Allen 29 August 2012 (has links)
The purpose of this study is to determine if Low Impact Development (LID) can effectively mitigate flooding under projected climate scenarios. LID relies on runoff management measures that seek to control rainwater volume at the source by reducing imperviousness and retaining, infiltrating and reusing rainwater. An event-driven hydrologic/hydraulic model was developed to simulate how climate change, land use and LID scenarios may affect runoff response in the Bowker Creek watershed, a 10km2 urbanized catchment located in the area of greater Victoria, British Columbia, Canada. The first part of the study examined flood impacts for the 2050s (2040-2069) following the A2 emissions scenario. For the 24-hour, 25-year local design storm, results show that projected changes in rainfall intensity may increase flood extents by 21% to 50%. When combined with continued urbanization flood extents may increase by 50% to 72%.
The second part of the study identified potential locations for three LID treatments (green roofs, rain gardens and top soil amendments) and simulated their effect on peak in-stream flow rates and flood volumes. Results indicate that full implementation of modeled LID treatments can alleviate the additional flooding that is associated with the median climate change projection for the 5-year, 10-year and 25-year rainfall events. For the projected 100-year event, the volume of overland flood flows is expected to increase by 1%. This compares favourably to the estimated 29% increase without LID. In term of individual performance, rain gardens had the greatest hydrologic effect during more frequent rainfall events; green roofs had minimal effect on runoff for all modelled events; and top soil amendments had the greatest effect during the heaviest rainfall events.
The cumulative performance of LID practices depends on several variables including design specifications, level of implementation, location and site conditions. Antecedent soil moisture has a considerable influence on LID performance. The dynamic nature of soil moisture means that at times LID could meet the mitigation target and at other times it may only partially satisfy it. Future research should run continuous simulations using an appropriately long rainfall record to establish the probabilities of meeting performance requirements.
In general, simulations suggest that if future heavy rainfall events follow the median climate change projection, then LID can be used to maintain or reduce flood hazard for rainfall events up to the 25-year return period. This study demonstrates that in a smaller urban watershed, LID can play an important role in reducing the flood impacts associated with climate change. / Graduate
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