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Återfyllnadsmassor vid sanering : Materialkrav med avseende på markmiljö och marklevande organismerLehman, Hanna January 2014 (has links)
The purpose of this study was to determinate what requirements there should be on refilling material used as soil remediation based on the soil environment, i.e. soil processes and factors important to soil-dwelling organisms. The study was conducted by investigating which parameters that is important for the soil environment and by comparing them with each other. To exemplify how the parameters may change in different locations, data for total organic carbon, dry matter (i.e. water content), and pH were analyzed from different locations before and after soil remediation. Dry matter, organic matter, pH, compaction, grain size, porosity and soil composition were found to have a significant impact on various soil processes and soil organisms. Field investigations were made to examine dry- and organic matter and pH. The results were indicating that dry matter increased and that the organic matter decreased when the area was refilled with a coarse material. This study showed that there should be requirements on the characteristics of refilling material such as; organic matter content, good water holding capacity, a pH that is as neutral as possible and that the soil should not be too compact. A conclusion from this study was that crushed rock may not be the optimal refilling material after soil remediation.
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Spatial Patterns in a 40-year-old Slash Pine (Pinus elliottii Engelm.) Forest in the Coastal Plain of South CarolinaLister, Andrew Joseph 15 January 1999 (has links)
A study was conducted at the Savannah River Site near Aiken, SC to: 1) characterize the spatial patterns of soil and forest floor variables (moisture, pH, soil phosphate, forest floor and soil carbon and nitrogen, and soil available nitrogen), 2) assess the spatial patterns of the plant community, and 3) investigate spatial relationships among the variables and between the variables and woody vegetation. Spatial soil and litter samples were collected on five 0.25 hectare plots, and relationships were explored using Pearson's correlation tests, canonical correlation analysis, variogram modeling and kriging.
The average range of spatial autocorrelation for the forest floor variables was >45 m, while that for soil variables was 12 m. Woody stem basal area exhibited spatial autocorrelation at ranges of less than 12 m, and was only weakly correlated with forest floor and soil resource patterns. Few strong spatial correlations among the forest floor and soil variables were observed. The means and variances of the variables were low, and differences in resource levels probably had little impact on the spatial pattern of vegetation. Results indicate a weak, differential effect of species group on litter quality, a weak relationship between large pine trees and soil nitrogen patterns, and a general homogeneity of the stands. / Master of Science
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Forensic taphonomy : investigating the post mortem biochemical properties of cartilage and fungal succession as potential forensic toolsBolton, Shawna N. January 2015 (has links)
Post mortem interval (PMI – the time elapsed since death and discovery) is important to medicolegal investigations. It helps to construct crucial time lines and assists with the identification of unknown persons by inclusion or exclusion of a suspect’s known movements. Accurate methodologies for establishing PMI are limited to about 48-hours. Such methods involve use of increasing levels of potassium in vitreous humour, and algor mortis. This study is two-fold. Firstly, it explores the biomolecular changes in degrading porcine cartilage buried in soil environments and its potential to determine PMI in the crucial two days to two months period. Trotters were interred in a number of graves at two distinct locations exhibiting dissimilar soil environments. Weekly disinterments (for 6 weeks) resulted in dissection for cartilage samples which were processed for protein immunoblot analyses and cell vitality assays. Results demonstrate that aggrecan, a major structural proteoglycan, produces high (230kDa) and low (38kDa) molecular weight cross-reactive polypeptides (CRPs) within cartilage extracellular matrix. The 230kDa CRP degrades in a reproducible manner irrespective of the different soil environments utilised. As PMI increases, aggrecan diminishes and degrades forming heterogeneous subpopulations with time. Immunodetection of aggrecan ceases when joint exposure to the soil environment occurs. At this time, aggrecan is metabolised by soil microbes. The molecular breakdown of cartilage proteoglycans has potential for use as a reliable indicator of PMI, irrespective of differing soil environments, beyond the 48-hours period. Likewise, vitality assays also demonstrated viable chondrocytes for as long as 35 PM days. The second component of this study examined the fungal activity associated with trotters buried below ground. Results indicate that fungal growth was considerably influenced by soil chemistry and changes in the environment. Fungal colonisation did not demonstrate temporal patterns of succession. The results of this study indicate that cartilage has the potential to prolong PMI determination well beyond the current 48- and 100-hour limitations posed by various other soft tissue methods. Moreover, the long-term post mortem viability of chondrocytes presents an opportunity to explore DNA extraction from these cells for the purpose of establishing a positive identification for unidentified remains. On the contrary, the growth and colonisation patterns of post putrefactive fungi in relation to decomposing porcine trotters proved to be futile for estimating PMI. Therefore, fungi may not be a suitable candidate for evaluating PMI during the early phase fungal activity.
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Modeling spatiotemporal influences on the hydrothermal environment of the seedling recruitment micrositeBullied, William John 14 September 2009 (has links)
Modeling the seedling recruitment microsite involves characterization of the soil environment of the shallow profile from which weed seedlings recruit. Understanding the environment of the seedling recruitment microsite is the prelude to weed emergence studies. Because of spatial and temporal heterogeneity of the recruitment microsite, sufficient measurements are often not feasible. An experiment was established in 2003 and 2004 across topography within an annually cropped field in south-central Manitoba to determine the effect that hillslope aspect and position, and soil residue and depth would have on microsite environment within the shallow seedling recruitment zone. Microclimatic, topographic, soil surface and soil properties were assessed in the context of the weed recruitment microsite. The soil water retention characteristic was measured by pressure plate to determine water availability to germinating seeds at the various topographic positions. The soil water characteristic was evaluated across topography and soil depth. Evaluation of the soil water characteristic by pedotransfer function indicated that a single soil water characteristic is representative of the recruitment zone. Field and laboratory experimental measurements were used as parameterization for the simultaneous heat and water (SHAW) model to generate continuous water and temperature profiles for the recruitment zone. Soil temperature and temperature fluctuation decreased with depth in the recruitment zone. Despite differences of texture, bulk density, and organic matter across topography and soil depth, the soil water characteristic differed only across topography. Soil water potential fluctuated considerably at the soil surface due to numerous precipitation events and direct evaporation. Implications for germinating seeds is that the seedling recruitment zone is influenced by spatial effects of topography and the vertical location of the seed microsite. Physical process based modeling used in this study to predict temperature and water within the seedling recruitment zone enables better understanding of interactions between above-ground microclimate and the recruitment microsite. Such interactions enable linkage between atmospheric models and recruitment models that can enhance our ability to evaluate crop management decisions.
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Modeling spatiotemporal influences on the hydrothermal environment of the seedling recruitment micrositeBullied, William John 14 September 2009 (has links)
Modeling the seedling recruitment microsite involves characterization of the soil environment of the shallow profile from which weed seedlings recruit. Understanding the environment of the seedling recruitment microsite is the prelude to weed emergence studies. Because of spatial and temporal heterogeneity of the recruitment microsite, sufficient measurements are often not feasible. An experiment was established in 2003 and 2004 across topography within an annually cropped field in south-central Manitoba to determine the effect that hillslope aspect and position, and soil residue and depth would have on microsite environment within the shallow seedling recruitment zone. Microclimatic, topographic, soil surface and soil properties were assessed in the context of the weed recruitment microsite. The soil water retention characteristic was measured by pressure plate to determine water availability to germinating seeds at the various topographic positions. The soil water characteristic was evaluated across topography and soil depth. Evaluation of the soil water characteristic by pedotransfer function indicated that a single soil water characteristic is representative of the recruitment zone. Field and laboratory experimental measurements were used as parameterization for the simultaneous heat and water (SHAW) model to generate continuous water and temperature profiles for the recruitment zone. Soil temperature and temperature fluctuation decreased with depth in the recruitment zone. Despite differences of texture, bulk density, and organic matter across topography and soil depth, the soil water characteristic differed only across topography. Soil water potential fluctuated considerably at the soil surface due to numerous precipitation events and direct evaporation. Implications for germinating seeds is that the seedling recruitment zone is influenced by spatial effects of topography and the vertical location of the seed microsite. Physical process based modeling used in this study to predict temperature and water within the seedling recruitment zone enables better understanding of interactions between above-ground microclimate and the recruitment microsite. Such interactions enable linkage between atmospheric models and recruitment models that can enhance our ability to evaluate crop management decisions.
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Relações solo-vegetação em áreas desenvolvidas sobre o Arenito Urucuia na APA do Rio Pandeiros / Soil-vegetation relationships in developed areas on the Sandstone Urucuia in APA do Rio PandeirosOliveira, Fábio Magalhães 28 June 2013 (has links)
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Previous issue date: 2013-06-28 / The state environmental protection área APAE do Rio Pandeiros", covers an area of 393 060 ha. It is located in the North of Minas Gerais and has as a representative compartment, the geomorphological unit "Plateau of the São Francisco", geologically dominated by rocks of Urucuia Formation, including most importantly the quartz sandstones cemented by siliceous materials. From the rocks of this unit have developed the soils classes Quartzarenic Neosol (RQ) and Red-Yellow Latossol (LVA), which are associated with vegetation typical to the "Cerrado". The aim of this study is to evaluate the soil attributes determinants for the establishment and development of different forms of cerrado vegetation identified in this compartment. Was conducted a transect in the study area, where were selected five sampling sites or environments, depending on the vegetation type observed, which were identified as Environment A (Cerrado s.s. sparse, associated with Quartzarenic Neosol), Environment B (Cerrado s.s. dense associated with Quartzarenic Neosol), Environment C (Cerrado s.s. typical, associated with Quartzarenic Neosol), Environment D (Cerrado s.s. typical, associated with Red-Yellow Latosol) and Environment E (Cerrado s.s. typical associated with Litolic Neosol). In each environment were done phytosociological studies, and three mini-trenches with a depth of 40 cm each were opened. Disturbed soil samples were collected at depths 0-20 cm and 20-40 cm for chemical and physical analysis and undisturbed samples at depth 0-20 cm for determining the bulk density and water retention curve. We also collected samples of litter present in each environment. Routine laboratory chemical analysis was performed, beside successive extractions of phosphorus using Mehlich-1, and the determination of total phosphorus. Further were made textural analysis and fractionation of sand grains, and the determination of moisture equivalent in soil samples with coated and uncoated sand, containing particles of colloidal nature. Scanning electron microscopy was performed to analyze the surface morphology of the grains of viisand and revealed the presence of depressions filled by smaller particles. The results demonstrated that the studied environments have oligotrophic characteristics. The various forms of cerrado soils are developed on soils of sandy texture and low natural fertility. It was concluded that in environments where the soil texture is predominantly sandy, the structure and development of vegetation is associated with the presence of the litter layer, probably related to nutrient cycling, while in those where the soil has clayey texture, the size of the vegetation is more related to chemical, physical and hydraulic soil properties. / A Área de Proteção Ambiental Estadual - APAE do Rio Pandeiros , abrange uma área de 393.060 ha, e localiza-se no Norte de Minas Gerais. A mesma possui como representativo compartimento a unidade geomorfológica Planalto do São Francisco , dominada geologicamente pelas rochas da Formação Urucuia, das quais se destacam os arenitos quartzosos cimentados com material silicoso. A partir das rochas dessa unidade, se desenvolveram os solos das classes Neossolo Quartzarênico (RQ) e Latossolo Vermelho-Amarelo (LVA), que se encontram associados à cobertura vegetal do tipo Cerrado. O objetivo desse estudo é avaliar os atributos edáficos determinantes para o estabelecimento e desenvolvimento de diferentes formas de vegetação de cerrado identificadas nesse compartimento. Foi realizado um transecto na área de estudo, onde foram selecionados cinco ambientes ou locais de coleta, em função do tipo fitofisionomico observado, os quais foram identificados como Ambiente A (Cerrado s.s. ralo, associado a RQ), Ambiente B (Cerrado s.s. denso, associado a RQ), Ambiente C (Cerrado s.s. típico, associado a RQ), Ambiente D (Cerrado s.s. típico, associado a LVA) e Ambiente E (Cerrado s.s. típico, associado a RL). Em cada ambiente foram realizados os estudos fitossociológicos, e abertas três mini-trincheiras com profundidade de 40 cm cada uma, onde foram coletadas amostras de solo deformadas nas profundidades de 0 a 20 cm e 20 a 40 cm, para análises química e física, e indeformadas na profundidade de 0 a 20 cm, para determinação da densidade do solo e curva característica de água. Foram obtidas ainda amostras da serapilheira presente em cada ambiente. As análises químicas de rotina foram efetuadas em laboratório, além de extrações sucessivas de P utilizando Mehlich-1, e a determinação do P total. Foram feitas ainda análise textural e fracionamento dos grãos de areia, bem como a determinação do equivalente de umidade em amostras de solo deformadas com capeamento e sem capeamento com partículas de natureza coloidal. A microscopia eletrônica de vvarredura (MEV) foi realizada para analisar a morfologia da superfície dos grãos de areia e revelou a presença de depressões preenchidas com partículas de dimensões menores. Os resultados permitiram constatar que os ambientes estudados possuem caráter oligotrófico. As diversas formas de cerrado se desenvolvem sobre solos de textura arenosa e de baixa fertilidade natural. Foi possível concluir que, nos ambientes onde a textura é predominantemente arenosa, a estrutura e o desenvolvimento da vegetação está associado a presença da camada de serapilheira, provavelmente relacionada com a ciclagem de nutrientes. Porém naqueles ambientes onde o solo possui textura mais argilosa, o porte da vegetação está mais relacionado com as propriedades químicas e físico-hídricas.
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Nitrogen Balance for a 23-Square Mile Minnesota WatershedJohnson, Jack D. 23 April 1971 (has links)
From the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona / The nitrogen balance of a watershed near the city of New Prague, Minnesota was evaluated as part of an overall study on lake and stream eutrophication. Although the n-balance of a humid Midwest watershed cannot be expected to be identical to that of an arid watershed, the processes are the same and differences should be mainly quantitive. Sources of input and causes of depletion are reviewed for 4 points in the nitrogen cycle: the atmospheric zone, the soil-atmosphere interface, the plant-root and soil-water zone and the surface water zone. In the New Prague watershed, commercial fertilizer and bulk precipitation were the major sources of input, contributing, respectively, 53% and 34.4% of the total input of 2.34 million lb/yr. Crop yield and soil or groundwater storage contributed 52.1% and 20.4% of non-enrichment depletions. The closeness of the values of crop yield and commercial fertilizer application was an unfortunate coincidence and is certainly not an indication that the entire fertilizer supply was taken up cry crops. In an arid environment, free from fertilized agriculture, bulk precipitation probably provides the major source of nitrogen compounds.
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Use and Abuse of Southwestern Rivers: The Desert FarmerAyres, J. E. 23 April 1971 (has links)
From the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona / The pre-Columbian Hohokam Indians occupied the major river drainages of central Arizona, and have been the subject of much intense archaeological research. Evidence indicates that the Hohokam began using river water for crop irrigation about 300 B.C., and modified and improved their irrigation systems over time, until the maximum extent of these systems was achieved about 900 a. D. Two types of water control seem to have been utilized: (1) the direct exploitation of rivers through the use of irrigation canals, (2) indirect use through controlled runoff within microdrainages at higher elevations before it reached the rivers. At first, probably only those parcels of land with optimal soils and drainage were used, but apparently population increases fostered by agriculture itself, combined with increasing social and political complexity, necessitated more and more exploitation of marginal lands. Eventually soil problems increased, imposing severe limitations on agriculture. These involved salt and alkali accumulation due to inadequate drainage, soil density and water logging. Additionally, the extension of cropping required the clearing of natural vegetation, which resulted in increased erosion and decreased available native food resources for periods when crops failed. The culture vanished completely about 1450 a. D., probably mainly because of their manner of river exploitation for irrigation. More recent archaeological studies are concentrating not only on river use but also on river abuse.
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