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SILVA, Francisca Gleiciane da. Condutividade hidráulica do solo saturado e fluxo preferencial em amostras confinadas de terra. 2015. 64 f. Dissertação (Mestrado em agronomia)- Universidade Federal do Ceará, Fortaleza-CE, 2015. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-08-30T20:09:46Z No. of bitstreams: 1 2015_dis_fgsilva.pdf: 1737179 bytes, checksum: 358ee3fc0ff3e673a09ab8f32131e84a (MD5) / Approved for entry into archive by Jairo Viana (jairo@ufc.br) on 2016-08-31T23:41:15Z (GMT) No. of bitstreams: 1 2015_dis_fgsilva.pdf: 1737179 bytes, checksum: 358ee3fc0ff3e673a09ab8f32131e84a (MD5) / Made available in DSpace on 2016-08-31T23:41:15Z (GMT). No. of bitstreams: 1 2015_dis_fgsilva.pdf: 1737179 bytes, checksum: 358ee3fc0ff3e673a09ab8f32131e84a (MD5) Previous issue date: 2015 / Understanding the processes related to the movement of water in soil profile is relevant to the management of soil and water resources. Hydraulic conductivity is an important soil property that affects this movement, but its determination in laboratory conditions requires that samples are contained in cylinders which can cause the presence of preferential flow through the soil wall interface. So, the goal of this work was to test the effect of increasing perimeter and height of the sample on saturated hydraulic conductivity in confined soil samples of different textures. Soil samples were collected and the following physical analyzes were performed: particle density, particle-size, water dispersed clay, soil porosity, and saturated hydraulic conductivity (Ko). Experimental data were analyzed in a randomized design for all variables, adopting a 4 x 5 factorial arrangement (four diameters x five heights of the cylinders), with six replications. The Shapiro- Wilk test was used to verify the normality of the data, F test for analysis of variance, and Tukey´s test for comparison of means (p<0.05). Classical descriptive statistics and multivariate analysis techniques were also employed. It was conclude that: a) the results support the hypothesis that the increase of the perimeter causes an increase of the saturated hydraulic conductivity; b) for the same increase of preferential flow area, the effect on the saturated hydraulic conductivity was higher for clay soil; c) the hypothesis that increased water path causes a change in the Ko values was rejected; d) for both soil classes increased water path did not affect the values of the saturated hydraulicconductivity. / A compreensão dos processos relacionados ao movimento da água no perfil do solo é relevante para o manejo do solo e dos recursos hídricos. A condutividade hidráulica é um importante atributo do solo que interfere nesse movimento, sendo que sua determinação na condição de laboratório requer que as amostras estejam confinadas em cilindros, o que pode causar a presença de fluxo preferencial pela interface solo/parede do cilindro. Objetivou-se nesse trabalho testar o efeito do aumento do perímetro e da altura da amostra sobre a condutividade hidráulica do solo saturado em amostras confinadas de terra de diferentes texturas. Foram coletadas amostras de terra para realização das análises físicas, a saber: densidade de partículas, granulometria, argila dispersa em água, porosidade do solo e condutividade hidráulica do solo saturado (Ko). Os dados experimentais foram analisados em delineamento inteiramente casualizado para todas as variáveis, adotandose o esquema fatorial 4 x 5 (quatro diâmetros e cinco alturas dos cilindros), com seis repetições. Foram aplicados os testes de Shapiro-Wilk para verificar a normalidade dos dados, o F para análise de variância e o de Tukey para a comparação da médias (todos a 5% de probabilidade). Também foi empregada a estatística descritiva clássica para algumas variáveis e técnicas multivariadas de análises. Conclui-se que a) aceita-se a hipótese de que o aumento do perímetro da amostra provoca aumento nos valores de condutividade hidráulica do solo saturado; b) para o mesmo aumento de área de fluxo preferencial, o efeito sobre a condutividade hidráulica do solo saturado para o solo argiloso foi maior; c) a hipótese de que o aumento do percurso da água causa alteração nos valores de Ko foi refutada; d) para ambas as classes de solos o aumento do percurso da água não foi determinante nos valores obtidos para condutividade hidráulica do solo saturado.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Understanding the processes related to the movement of water in soil profile is relevant to the management of soil and water resources. Hydraulic conductivity is an important soil property that affects this movement, but its determination in laboratory conditions requires that samples are contained in cylinders which can cause the presence of preferential flow through the soil wall interface. So, the goal of this work was to test the effect of increasing perimeter and height of the sample on saturated hydraulic conductivity in confined soil samples of different textures. Soil samples were collected and the following physical analyzes were performed: particle density, particle-size, water dispersed clay, soil porosity, and saturated hydraulic conductivity (Ko). Experimental data were analyzed in a randomized design for all variables, adopting a 4 x 5 factorial arrangement (four diameters x five heights of the cylinders), with six replications. The Shapiro- Wilk test was used to verify the normality of the data, F test for analysis of variance, and TukeyÂs test for comparison of means (p<0.05). Classical descriptive statistics and multivariate analysis techniques were also employed. It was conclude that: a) the results support the hypothesis that the increase of the perimeter causes an increase of the saturated hydraulic conductivity; b) for the same increase of preferential flow area, the effect on the saturated hydraulic conductivity was higher for clay soil; c) the hypothesis that increased water path causes a change in the Ko values was rejected; d) for both soil classes increased water path did not affect the values of the saturated hydraulicconductivity. / A compreensÃo dos processos relacionados ao movimento da Ãgua no perfil do solo à relevante para o manejo do solo e dos recursos hÃdricos. A condutividade hidrÃulica à um importante atributo do solo que interfere nesse movimento, sendo que sua determinaÃÃo na condiÃÃo de laboratÃrio requer que as amostras estejam confinadas em cilindros, o que pode causar a presenÃa de fluxo preferencial pela interface solo/parede do cilindro. Objetivou-se nesse trabalho testar o efeito do aumento do perÃmetro e da altura da amostra sobre a condutividade hidrÃulica do solo saturado em amostras confinadas de terra de diferentes texturas. Foram coletadas amostras de terra para realizaÃÃo das anÃlises fÃsicas, a saber: densidade de partÃculas, granulometria, argila dispersa em Ãgua, porosidade do solo e condutividade hidrÃulica do solo saturado (Ko). Os dados experimentais foram analisados em delineamento inteiramente casualizado para todas as variÃveis, adotandose o esquema fatorial 4 x 5 (quatro diÃmetros e cinco alturas dos cilindros), com seis repetiÃÃes. Foram aplicados os testes de Shapiro-Wilk para verificar a normalidade dos dados, o F para anÃlise de variÃncia e o de Tukey para a comparaÃÃo da mÃdias (todos a 5% de probabilidade). TambÃm foi empregada a estatÃstica descritiva clÃssica para algumas variÃveis e tÃcnicas multivariadas de anÃlises. Conclui-se que a) aceita-se a hipÃtese de que o aumento do perÃmetro da amostra provoca aumento nos valores de condutividade hidrÃulica do solo saturado; b) para o mesmo aumento de Ãrea de fluxo preferencial, o efeito sobre a condutividade hidrÃulica do solo saturado para o solo argiloso foi maior; c) a hipÃtese de que o aumento do percurso da Ãgua causa alteraÃÃo nos valores de Ko foi refutada; d) para ambas as classes de solos o aumento do percurso da Ãgua nÃo foi determinante nos valores obtidos para condutividade hidrÃulica do solo saturado.

Following a call from Linton (2010) to think more relationally about water this thesis seeks to explore the infolding and unfolding relations that take-form between bodies around particular characteristics of freshwater. There is a tradition of exploration regarding the sustainability, quality, monitoring and management of water when we encounter research on human associations with fluvial hydrology, and whilst this work is important, this project looks to enrol more nascent and contemporary geographical themes to broaden our understanding of encounters with freshwater landscapes, and take a more relational approach to fluvial geographies. These works then shall address a gap in the geographical literature and describe the personal, pre-personal and affective worlds that emerge when bodies become down by the river. Whilst this is not specifically a walking project, walking the course of the River Severn serves as a trajectory along which processual ideas of bodies on the move shall be mobilised. A series of creatively written segues will link together a sequence of theoretical and conceptually driven site ontologies (Marston et al 2005; Woodward et al 2010) and relations associated with the Severn and freshwater more broadly. The flow and form of the thesis will reflect the multivariant characteristics of water and its varying speeds and slownesses. The chapters will step into puddles, mooch about in a ships graveyard, rethink the source of a river, paddle a coracle and set the scene for how an ontological, relational approach to fluvial landscapes can contribute to geographical thinking. The works will focus on human-nonhuman relations, vibrant materialities and elemental mobilities, in so doing enable further understanding of how we can apprehend sites as moments of coherence in a turbulent world, and contribute to broadening our scope of knowledge of the more-than-human.

Sunflower plants (Helianthus annus, var. Russian mammoth) were grown in Hogland nutrient solution. The roots (after being subjected to treatments with either respiratory inhibitors or respiratory stimulators) were used to measure the flux of water Jw, flux of solute Js , and the rate of respiration Jo. The thermodynamic theory of irreversible processes was used to examine the interaction between fluxes, and the changes in conductivity under different treatments. The rate equations for a root membrane of unit thickness were developed as: Jw = LwwVw∆p + LwsRT ln C1s/C2s +LwoRT ln C1o/C2o Js = LswVx∆p + LssRT ln C1s/C2s + LsoRT ln C1o/C2o Jo = LowVw∆p + Los RT ln C1s/C2s + LooRT ln C1o/C2o Where: Lww, Lss, Loo are the direct transfer coefficients for water, solute , and oxygen; and Lws, Lsw, Lwo, Low, Lso, Los are the interaction or linked transfer coefficients; Vw partial molal volume (or specific volume) of water , ∆p the difference in pressure between the external solution and xylem: C1s and C2s , C1o and C2o are the salt and oxygen concentration in external solution and xylem respectively. The results showed that: 1. The nonlinearity of the flux of water through the root system of sunflower is due to causes associated with the membrane (mainly the permeability). 2. The increase in respiration did not increase the permeability of the membrane. 3. The uptake of water due to solute potential under transpiring conditions is small, but important. 4. The uptake of solute in normal root systems is by active process fromsolutions to the zylem and then moves passively to the leaves. 5. An increase in passive water uptake might cause an increase of respiration of the root.

<p>The Earth’s surface contains of 71% oceans and a large part of the global carbon cycle takes place in the oceans. In the aquatic environment, the sediment-water interface plays an important role for the mineralisation of organic material. One factor that can affect the mineralisation is resuspension. Resuspension cause mixing of surface sediments and bottom water and result in a redistribution of the sediment when it settles again. Resuspension also increases the transport of oxygen into the sediment, reduces the diffusive boundary layer surrounding particles, and enhance the nutrient uptake. Resuspension can be induced by both wave action and bottom currents and is a common physical process in both shallow coastal areas and in the deep ocean. Human impacts, such as dredging and trawling, can also cause resuspension.</p><p>The effect of resuspension on mineralisation of organic material was studied in two experiments ex situ during December to April 2004/2005. The aim for Experiment 1 was to investigate how the intensity of the resuspension event affects the degradation rate. The aim for Experiment 2 was to investigate how different concentrations of resuspended sediment affect the degradation rate of organic matter. Sediment samples were collected in December and late March at a marine field station, Askö, Sweden. Sediment and bottom water were transferred to and incubated in sealed bottles. For Experiment 1, resuspension was created in bottles with a specially designed rotary table, creating different intensity of water movements. In Experiment 2, bottles with different concentrations of sediment were put on an ordinary rotary table. The mineralisation rates were in both experiments monitored by daily sampling of sediment-water slurry, and analysed for total inorganic carbon by a gas chromatography with a thermal detector, GC-TCD.</p><p>Results from Experiment 1 did not show any clear patterns regarding inorganic carbon formation. Experiment 2 did show clear patterns for two of six replicates of mineralisation of organic material. For these replicates the mineralisation rate were low according to previous studies. However, the sediment concentration seems to not affect the mineralisation rate. For both experiments, valuable information on how to better design experiments to investigate the importance of resuspension and the effect of mineralisation of organic material was yielded. Hence, further studies are needed to continue the investigation of the importance of resuspension for the mineralisation rate of organic material, and its impacts on the nutrient fluxes in the oceans.</p>

The Earth’s surface contains of 71% oceans and a large part of the global carbon cycle takes place in the oceans. In the aquatic environment, the sediment-water interface plays an important role for the mineralisation of organic material. One factor that can affect the mineralisation is resuspension. Resuspension cause mixing of surface sediments and bottom water and result in a redistribution of the sediment when it settles again. Resuspension also increases the transport of oxygen into the sediment, reduces the diffusive boundary layer surrounding particles, and enhance the nutrient uptake. Resuspension can be induced by both wave action and bottom currents and is a common physical process in both shallow coastal areas and in the deep ocean. Human impacts, such as dredging and trawling, can also cause resuspension. The effect of resuspension on mineralisation of organic material was studied in two experiments ex situ during December to April 2004/2005. The aim for Experiment 1 was to investigate how the intensity of the resuspension event affects the degradation rate. The aim for Experiment 2 was to investigate how different concentrations of resuspended sediment affect the degradation rate of organic matter. Sediment samples were collected in December and late March at a marine field station, Askö, Sweden. Sediment and bottom water were transferred to and incubated in sealed bottles. For Experiment 1, resuspension was created in bottles with a specially designed rotary table, creating different intensity of water movements. In Experiment 2, bottles with different concentrations of sediment were put on an ordinary rotary table. The mineralisation rates were in both experiments monitored by daily sampling of sediment-water slurry, and analysed for total inorganic carbon by a gas chromatography with a thermal detector, GC-TCD. Results from Experiment 1 did not show any clear patterns regarding inorganic carbon formation. Experiment 2 did show clear patterns for two of six replicates of mineralisation of organic material. For these replicates the mineralisation rate were low according to previous studies. However, the sediment concentration seems to not affect the mineralisation rate. For both experiments, valuable information on how to better design experiments to investigate the importance of resuspension and the effect of mineralisation of organic material was yielded. Hence, further studies are needed to continue the investigation of the importance of resuspension for the mineralisation rate of organic material, and its impacts on the nutrient fluxes in the oceans.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2009. / Härtill 4 uppsatser.