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Mine and industrial site revegetation in the semi-arid zone, North-Eastern Eyre Peninsula, South AustraliaAtkinson , Victoria January 2005 (has links)
This research aims to develop the present knowledge of arid zone rehabilitation by scientifically testing topsoiling and seeding treatments on the Eyre Peninsula, South Australia, in a way that enables the widest application and comparison to other mining leases throughout the arid lands.
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Spatial and temporal extent of land degradation in a communal landscape of KwaZulu-Natal, South Africa.January 2009 (has links)
Land degradation in communal rangelands is one of the problems that lowers land / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
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Erfassung und Bewertung von degradierten Böden mit Fernerkundung und GIS in Nordwest-SyrienAl Mohamed, Ismail 06 July 2011 (has links) (PDF)
Due to a high population growth (approx. 2.5 % p.a) the food-sector in Syria is facing in-creasing problems. An enormous increase in population results in increased demand for food. This has adversely affected the socio-economic and ecological development in the country. Intensive use of various natural resources has led to significant changes in land use pattern, especially due to use of inappropriate methods in the agricultural sector. The increasing anthropogenic pressure on the sensitive ecological structure of the respective area causes environmental damages, in particular degradation of soil characteristics. In the semi-arid and arid eco-climatic zones vast areas are facing desertification. Soil erosion through water represents the main form of land degradation in the north-west of Syria. Particularly vulnerable are the soils with a shallow or no vegetation cover, such as the soils found in the Mediterranean hills, where olives are cultivated.
For this research the Afrin region, located in the northwest of Syria, was selected as study area, in order to analyse and assess the extent of degradation. For estimation of erosion the relevant parameters of the “Universal Soil Loss Equation USLE” were used. These para-meters were adapted and integrated through remote sensing and GIS. LANDSAT TM and ASTER satellite imagery of the investigated area were used for this purpose. Data were acquired at the end of the dry season. In order to achieve an accurate evaluation and high-quality comparison of multi-temporal satellite data, imagery was firstly geometrically and atmospherically corrected and then analysed. The vegetation coverage and its current de-gradation level were investigated by spectral mixture analysis (SMA). The digital elevation model (DEM) derived from ASTER data was utilized to generate the slope gradient (S) and the slope length (L). In addition to the laboratory analysis, grain size index (GSI) and SMA were used for the characterization and mapping of soil erodibility. Land-use/land-cover classification and change detection were determined by using pixel-based classification procedures (maximum likelihood classification) and post classification methods respectively. Required samples for land cover classification of the remotely sensed data were collected during the field work, in addition to the soil samples for soil analysis.
The results of this study show that advanced methods of remote sensing and GIS provide powerful tools not only for a better understanding of the land use changes, but also for an accurate assessment of land degradation and desertification. This knowledge, in turn, con-tributes highly towards developing effective and appropriate management strategies for sustainable use and conservation of natural resources in the north-west of Syria
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Seed viability in topsoil stockpiles used for arid zone minesite rehabilitation in the Middleback Ranges of South AustraliaLangley , Gail January 2002 (has links)
The aim of this research is to assess various options for the management of topsoil stockpiles on disturbed lands and to evaluate the viability and germinability over time of the seedbanks in these stockpiles for use in rehabilitation. To predict their success, experimental trials were designed and conducted.
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Mine and industrial site revegetation in the semi-arid zone, North-Eastern Eyre Peninsula, South AustraliaAtkinson , Victoria January 2005 (has links)
This research aims to develop the present knowledge of arid zone rehabilitation by scientifically testing topsoiling and seeding treatments on the Eyre Peninsula, South Australia, in a way that enables the widest application and comparison to other mining leases throughout the arid lands.
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The effect of poplar stand density on hill country pastures : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy (PhD), Massey University, Palmerston North, New ZealandWall, Andrew James January 2006 (has links)
Page xvi is missing from both the electronic and print copy / One-third of the North Island of New Zealand has been identified as requiring increased soil conservation if pastoral farming is to be sustainable. For over 50 years the planting of widely spaced poplar trees (Populus spp.) has been one of the main methods used to control soil erosion on hill pastures. Research has shown that these plantings have successfully decreased soil erosion but their impact on the productivity of pastoral farming has received little research attention. The research that has been undertaken has found poplars can suppress understorey pasture production by up to 40%, suggesting that farmers require more research information on the impact of planting conservation trees on the productivity of their farm if the use of conservation trees is to be more widely adopted on erosion prone land. The objective of this thesis was to provide comprehensive data on the relationship between the range of poplar densities used for soil conservation on the light and soil under poplars, and consequently the effect on understorey pastures. Three field sites on commercial sheep and beef hill farms, in regions with contrasting summer soil moisture availability, Manawatu (one site) and Central Hawke's Bay (two sites), were monitored for two years. Tree stocking rates ranged from 0 to 375 trees/ha. Measurements were based on units of four trees with most measurements either directly below the tree crowns or in the gaps between the trees, but more intensive transect measurements were also made. Photosynthetically active radiation (PAR) and the ratio of red to far red light (R:FR) were measured under the trees and in open pasture controls. Stand density indices used included all the commonly used measures of tree canopies, including digital photography, and stem diameter at breast height (DBH). PAR transmission was inversely related to all of the stand density indices with canopy closure based on digital photographs being the most robust of the indices used. PAR under the trees, relative to open pasture, was greater in the gaps than below tree crowns. Under a completely closed canopy, PAR transmission was reduced to 15-20% and 50-55% of the open pasture in summer and winter, respectively. The RFR under the trees, relative to open pasture, decreased markedly at high stand densities (allowing less than 40% PAR transmission) in summer, but was similar in winter. The change in PAR under the trees was shown to be a major factor limiting pasture growth, particularly directly below the tree crowns. For both summer and winter, canopy closure measured with a standard digital camera was strongly related to stand level PAR transmission (r2=0.88-0.97; P<0.0001) and was also a practical method of measuring canopy closure in the field. The soil measurements confirmed earlier research that soil pH increases under mature poplar trees. There was a 0.2 - 0.7 unit increase in soil pH in the upper 75 mm of soil over both contrasting regions. The soil fertility under the trees in terms of requirements for pasture growth was similar to that of the open pasture with calcium and potassium up to 2.2 and 9.0 quick test units higher in the soil under the trees than in the open pasture, respectively. The direct cause of the increased concentration of some cations under the trees was the annual tree leaf litter. Overall, the soil fertility under the trees had the potential to produce similar pasture production to that of the open pasture with the added advantage of less acid conditions. Averaged over all sites the respective annual net herbage accumulation (ANHA) under poplar canopy closures of 25, 50 and 75 % was estimated from the equations developed to be 77, 60 and 48% of the open pasture. The greatest decrease was directly below the tree crowns where at canopy closures greater than 20% the ANHA was a relatively constant 50% of open pasture. In the vertically projected gap between trees the ANHA decreased by 6.6% relative to open pasture for each 10% increase in canopy closure. At approximately 80% canopy closure there was no difference between the ANHA directly below the trees and in the gap. Pasture net herbage accumulation (NHA) under the trees relative to open pasture was at its lowest in summer and autumn (36% of open pasture under a closed canopy), and at its greatest in early spring before tree canopy leafed out (72% of open pasture under a closed canopy). The botanical composition and feed value of the pasture under the trees was broadly similar to that of the open pasture. The greatest impact of the poplars on the pasture was decreased NHA due to shading. The decrease in NHA directly below mature unpruned poplars is substantial and would decrease farm profitability if the poplar stand density were high over a large area of the farm. The use of poplars for soil conservation is essential but these results show the importance of managing trees through pruning and thinning so that canopy closure is minimised. ANHA under the trees can be maintained at 75% of the open pasture if canopy closure is prevented from exceeding 30-40%.
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An assessment of synthetic landfill leachate attenuation in soil and the spatial and temporal implications of the leachate on bacterial community diversity /Govender, Kamenthren. January 2008 (has links)
Thesis (M.Sc.) - University of KwaZulu-Natal, Pietermaritzburg, 2008. / Full text also available online. Scroll down for electronic link.
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Rizika polutantů v půdě a jejich vliv na zdraví lidí / The hazards of soil pollutants and their effects on the human healthŠVEHLOVÁ, Jana January 2009 (has links)
Good soil condition belongs to the basic requirements of well-ballanced environment. That is why the soil has to correspond to hygienic requirements and be protected against substances harmful to human health, e.g. toxic materials, germs of transmissible illnesses and parasites. The most common cause of soil contamination is anthropogenic incidence. Contaminated soil belongs to waste and has to be removed in a proper way. is A special way of waste removal is soil decontamination. Its goal is to remove harmful substances and regain the original use of the soil.
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Variabilidade da agregação em amostras de solos agrícolas como indicador de qualidade: uma proposta metodológica / Variability of aggregation as quality indicator in agricultural soils: a methodological proposalPeche Filho, Afonso 02 March 2018 (has links)
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Previous issue date: 2018-03-02 / As questões ambientais que envolvem os efeitos do manejo e da degradação do solo necessitam de forma acelerada de pesquisa e muita extensão. Novos saberes e conhecimentos têm alcançado parte da comunidade acadêmica, mas ainda está aquém das necessidades para técnicos e leigos envolvidos em trazer soluções para problemas da ocupação, uso e degradação das terras. O manejo e recuperação ambiental de áreas degradadas são complexos e requerem diferentes tecnologias para o diagnóstico e avaliação. O uso de indicadores como diâmetro médio geométrico e distribuição percentual de agregado são parâmetros de uso consolidados, mas trazem limitações para questões complexas como o diagnostico do estado e condição de agregação do solo. A agregação do solo vem sendo estudada desde o inicio do século passado, mas são poucos os avanços conseguidos em popularizar a analise de agregação do solo agrícola como uma ferramenta laboratorial e prática. Além de que, falta conhecimento para popularizar a condição de agregação como informação de uso corrente. O uso de imagens obtidas e processadas em alta resolução permite sua aplicação em diferentes ramos da ciência, podendo ser aplicada nos estudos relacionados com o processo de agregação permitindo viabilizar o mais conhecimento ao processo. Este trabalho tem como objetivo desenvolver uma proposta metodológica para determinar a condição da qualidade de agregação, com base na tipificação de agregados e nos efeitos da variabilidade de composição em amostras de solo agrícola. Foram utilizados parâmetros relacionados com a forma, superfície e biogênese de agregados como indicadores de variabilidade da agregação do solo em duas amostras de latossolo vermelho de textura média, sendo que uma delas é referente a uma parcela de solo que recebeu um produto fertilizante/agregante Microgeo® e outra parcela sem ter recebido o produto. A obtenção dos agregados foi através do processo de peneiramento via seca utilizando cinco peneiras de diferentes calibres. A análise de agregados foi realizada em laboratório a partir de uma sub-amostra contendo 100 agregados oriundos de cada peneira específica, totalizando 500 agregados por amostras individuais de solo, perfazendo um total de 1000 agregados avaliados. A partir da obtenção de 1000 imagens fotográficas, com auxílio de um programa de processamento de imagens, obtêm-se um banco de dados referentes aos parâmetros morfométricos. Através do uso de tecnologia Fuzzy obteve-se um banco de dados numéricos referente à tipificação com base na análise visual da forma, superfície e biogênese dos agregados. Para cada conjunto de dados foi elaborado uma representação gráfica da variabilidade e seu respectivo quadro analítico descritivo. Com auxílio de medidas separatrizes do tipo quintis os dados foram classificados de acordo com a tipologia de ocorrência. Foram utilizados como parâmetros morfométricos o “diâmetro de Feret”, e como parâmetro de tipificação rugosidade de superfície e a “saída Fuzzy de tipificação” (os valores de integração com uso da tecnologia Fuzzy) o qual denominamos “Indicie Fuzzy de Tipificação”. Os resultados permitem afirmar que o trabalho atendeu os objetivos proposto de oferecer para sociedade uma “metodologia para qualificar a agregação em amostras de solos agrícolas”. Os resultados permitem aceitar as hipóteses formuladas e concluir que o estudo sobre efeitos da variabilidade permite quantificar, diagnosticar e qualificar o estado de agregação de amostras de solo. / Environmental issues involving the soil management effects and degradation are increasing and need to be extensively researched to be managed. New knowledge about solutions has been produced by academic research, but is still insufficient to solve the problems faced by technicians and other people involved to the field land use planning and degradation problems. Furthermore, the management of soil quality and land reclamation is complex, requiring different technologies for diagnosis and evaluation. The use of indicators, such as geometric mean diameter and percentage distribution of aggregate size, represents classical approaches, but both have limitations in treating the complexity of soil aggregation process. The soil aggregation has been studied since the beginning of the last century, but few advances have been made to popularize it to analyze agricultural soil quality. There are several difficulties to develop laboratory routines and practical tool to evaluate it. The use and processing of high resolution images have been widely applied in several fields of science and represents an interesting solution to study soil aggregation. To fill the existing gap, this works presents a methodological proposal to assess the quality of soil aggregation, by a classification of soil aggregates in terms of composition and variability. Agricultural soil aggregates were analyzed by three attributes: shape, surface and biogenesis. These parameters were used as indicators of soil aggregation quality, and the variability on each parameter was evaluates for two samples of medium texture red latosol, one of them referring to a plot of soil that received a fertilizer/aggregate product Microgeo® and another without receiving it. The aggregates were passed through the dry sieving process using five different sizes. The laboratorial analysis was performed by subsampling 100 aggregates from each sieve, totaling 500 aggregates per soil samples, and making a total of 1000 aggregates. Each soil aggregate was photographed, totalling1000 pictures, later processed on ImageJ. All results were organized in a database, containing information about the morphometric parameters of all soil aggregates. Fuzzy Logic was employed to transform the aggregate type into numeric values, using the visual analysis of the shape, surface and biogenesis. For each data set, a graphical representation of the variability and its descriptive statistics were calculated, producing an analytical framework. Statistical measures were used to classify the samples according to occurrence of aggregate type. To classify the samples and two sets of indexes were developed. The first one was based on the "Feret diameter", used as morphometric indicator, and the second one based on the "Fuzzy typing output", index produced by the integration of the values of shape, surface and biogenesis by a Fuzzy Inference System, which we call "Fuzzy index of typing". These results allowed affirming that the work fulfill the proposed objectives, offering to society a "methodology to qualify the aggregation quality in samples of agricultural soils". The results also allowed us to accept the formulated hypotheses and conclude that the study of variability can be used to quantify, diagnose and qualify the state of aggregation of soil samples.
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VARIABILIDADE ESPACIAL DO TIFTON 85 EM FUNÇÃO DOS ATRIBUTOS QUÍMICOS E FÍSICOS DO SOLO / SPATIAL VARIABILITY OF BIOMASS PRODUCTION OF TIFTON 85 DEPENDING ON CHEMICAL AND ATTRIBUTES PHYSICAL SOIL SMALL PROPERTYBier, Diogo Rafael 05 August 2013 (has links)
The aim of this study was to use Precision Farming tools to assess the spatial variability of production of green mass (MV), dry mass (MS) and accumulation of nitrogen (N), phosphorus (P) and potassium (K) of tifton 85 depending on the chemical and physical attributes of the soil in a small property. The study was conducted during the months of October to December 2012, in the municipality of Rio Grande do Sul-RS, Brazil View. The study was conducted in an area of 4.3 ha, divided into a grid of sampling 0.25 ha, resulting in 16 sampling points, where they performed two reviews for the determination of the spatial variability of the production of MV, MS and accumulation of NPK at tifton 85. For the presentation of this work the study was divided into two chapters, with the first, are presented the results of the survey of soil chemical attributes of layers: 0.00-0.10 0.10 0.20 m and 0.40 m 0.20-m, and its effect on the production of MV, MS and accumulation of NPK at tifton 85. In the second chapter studied the spatial variability of physical attributes of soil in layers of 0.00-0.35 m and its correlation with the production of MV and MS of tifton 85. The data obtained were submitted to descriptive statistics and correlation analysis by linear array of Pearson. From the results, it was concluded that the production of MV and MS and accumulation of NPK at tifton 85 feature a spatial variability considered of moderate to high. The base saturation was the only chemical soil attribute which showed correlation with the production of MS and MV of tifton 85. The values of N and P in tifton 85 MS, correlation with the chemical attributes of the soil base saturation, pH in water and H + Al. The physical attributes of the soil showed significant correlations with the production of MV and MS of tifton 85 were the ICPL, density and microporosity, being these more relevant as rainfall decreases. / O objetivo deste estudo foi utilizar ferramentas de Agricultura de Precisão para avaliar a variabilidade espacial da produção de massa verde (MV), massa seca (MS) e acúmulo de nitrogênio (N), fósforo (P) e potássio (K) do tifton 85 em função dos atributos químicos e físicos do solo em uma pequena propriedade. O estudo foi realizado durante os meses de outubro a dezembro de 2012, no município de Vista Gaúcha - RS, Brasil. O estudo foi realizado em uma área de 4,3 ha, dividida em uma grade amostral de 0,25 ha, resultando em 16 pontos amostrais, nos quais se realizou duas avaliações para a determinação da variabilidade espacial da produção de MV, MS e acumulo de NPK pelo tifton 85. Para a apresentação deste trabalho o estudo foi dividido em dois capítulos, sendo que no primeiro, são apresentados os resultados do levantamento dos atributos químicos do solo nas camadas de: 0,00 0,10 m, 0,10 0,20 m e 0,20 0,40 m, e seus efeitos sobre a produção de MV, MS e acúmulo de NPK pelo tifton 85. No segundo capitulo se estudou a variabilidade espacial dos atributos físicos do solo nas camadas de 0,00 0,35 m e as suas correlações com a produção de MV e MS do tifton 85. Os dados obtidos foram submetidos a análises estatísticas descritivas e de correlação pela matriz linear de Pearson. A partir dos resultados concluiu-se, que a produção de MV e MS e acúmulo de NPK pelo tifton 85 apresentam uma variabilidade espacial considerada de moderada à alta. A saturação por bases foi o único atributo químico do solo que apresentou correlação com a produção de MS e MV do tifton 85. Os valores de acúmulo de N e de P na MS do tifton 85, apresenta correlação com os atributos químicos do solo saturação por bases, pH em água e H+Al. Os atributos físicos do solo que apresentaram correlações significativas com a produção de MV e MS do tifton 85 foram o ICPL, densidade e microporosidade, sendo esses mais relevantes à medida que diminui a pluviosidade.
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