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Summary Collecting and interpreting permeability data in karst systems is considered complicated due to three distinct properties of these systems. First, the distribution of high permeability features may be one-dimensional features difficult to detect with wells, or may be so high in the wells the upper measurement limit is encountered during aquifer testing. Secondly, turbulent flow may make the application of continuum hydraulic principles difficult. Finally, permeability in these systems commonly increases with the scale of measurement. The aquifer for Sete Lagoas, Brazil, was used to evaluate a permeability combination methodology testing the permeability structure across a range of spatial scales in order to develop a quantitative model of hydraulically active features consistent across all scales of measurement, from matrix properties to regional-scale flow. The aquifer in this study has some wells without measurable drawdown during pumping due to high permeability. Data indicated an increase in permeability from the small- to the well-scale and a decrease from the well- to regional-scale due to the localized development of a karst bedding plane dissolution in one structurally controlled region of the aquifer. The matrix permeability in the region is very low and the secondary porosity is mostly filled by secondary precipitation of calcite. Based on measurement technique, the permeability data vary over many orders of magnitude, while the physical size of permeable features of the aquifer are consistent across the scales of data collection. The geometry provides a quantitative understanding of the scale effects of permeability measurements.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:50:05Z No. of bitstreams: 1 S0100-69162006000100010.pdf: 144323 bytes, checksum: f75e45b2152ee62446dbc6d60773d5d7 (MD5) Made available in DSpace on 2013-08-22T18:50:05Z (GMT). No. of bitstreams: 1 S0100-69162006000100010.pdf: 144323 bytes, checksum: f75e45b2152ee62446dbc6d60773d5d7 (MD5) Previous issue date: 2006-04-01 Made available in DSpace on 2013-09-30T19:40:42Z (GMT). No. of bitstreams: 2 S0100-69162006000100010.pdf: 144323 bytes, checksum: f75e45b2152ee62446dbc6d60773d5d7 (MD5) S0100-69162006000100010.pdf.txt: 32104 bytes, checksum: 6557cca4b1d07ae15e81f086982d9801 (MD5) Previous issue date: 2006-04-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:17:07Z No. of bitstreams: 2 S0100-69162006000100010.pdf: 144323 bytes, checksum: f75e45b2152ee62446dbc6d60773d5d7 (MD5) S0100-69162006000100010.pdf.txt: 32104 bytes, checksum: 6557cca4b1d07ae15e81f086982d9801 (MD5) Made available in DSpace on 2014-05-20T13:17:07Z (GMT). No. of bitstreams: 2 S0100-69162006000100010.pdf: 144323 bytes, checksum: f75e45b2152ee62446dbc6d60773d5d7 (MD5) S0100-69162006000100010.pdf.txt: 32104 bytes, checksum: 6557cca4b1d07ae15e81f086982d9801 (MD5) Previous issue date: 2006-04-01 O presente trabalho teve por objetivo avaliar o efeito da subsolagem e da adubação verde nas propriedades físicas de um Latossolo Vermelho distrófico típico, cultivado com citros (laranjeira Valência). Os tratamentos empregados foram: manejo mecânico das plantas invasoras com roçadora (Testemunha); subsolagem em um lado da planta na entrecopa; subsolagem nos dois lados da planta na entrecopa, e semeadura direta de Crotalaria spectabilis na entrecopa. As propriedades físicas do solo avaliadas foram: porosidade total, macroporosidade, microporosidade, densidade, resistência mecânica à penetração vertical e condutividade hidráulica. Na avaliação efetuada na safra 2001-2002, obtiveram-se os maiores valores de densidade do solo e resistência do solo à penetração vertical, e os menores valores de macroporos e condutividade hidráulica do solo nas entrecopas com e sem tráfego no pomar, em relação à região da copa, principalmente na camada de 0,0-0,2 m de profundidade. Os tratamentos aplicados não surtiram efeitos positivos significativos nas propriedades físicas do solo. The present work was conducted to evaluate the effects of subsoiling and green manuring on soil physical properties of a Typical Haplustox soil cultivated with Valencia orange trees. The treatments applied were mechanic management of the invaders plants with shredder (witness); subsoiling in one side of the plant on between crown; subsoiling on both sides of the plant on between crown and direct seeding of Crotalaria spectabilis on between crown. The soil physical properties evaluated were porosity, macro porosity, micro porosity, bulk density and mechanical resistance to vertical penetration and hydraulic conductivity. The evaluation effectuated to the harvest in 2001/2002, got the greatest values of bulk density and soil resistance to vertical penetration, and the least values of macro porosity and soil hydraulic conductivity on the region between crown, with and without traffic in relation to the crown, especially on the layer 0.0-0.2 m of depth. The treatments used did not result in positive significative effects on the soil physical properties. UNESP Departamento de Solos e Adubos UNESP Departamento de Solos e Adubos

Variáveis físicas do solo foram investigadas em parcelas de floresta de terra firme submetidas à extração seletiva de madeira na Amazônia central. Foram obtidas curvas de retenção de água no solo, juntamente com medidas de água disponível no solo às plantas, densidade do solo e porosidade total. Medidas de temperatura do solo foram realizadas por mais de 13 meses, considerando seis tratamentos: controle, centro da clareira, borda da clareira, borda da floresta remanescente, floresta remanescente e trilha do trator. Medidas de condutividade hidráulica de solo saturado foram feitas na floresta e em clareiras, sem distinguir os tratamentos. O solo revelou baixa capacidade de armazenar água disponível: apenas 11 a 18% da água pode estar disponível às plantas, num perfil de 1 m de profundidade. A temperatura das camadas superiores do solo foi influenciada pela extração seletiva de madeira: nas clareiras abertas, a luz chega com mais intensidade no solo, proporcionando temperaturas mais elevadas no centro e nas bordas das clareiras do que no controle e na floresta remanescente. Soil physical variables were investigated in forest plots submitted to selective logging in Central Amazonia. After logging, soil samples were collected to obtain soil water retention curves and measure: available soil water to the plants, soil density, and total porosity. Temperature measurements were carried out for 13 months, considering six treatments: control, center of the gaps, edge of the gaps, edge of the remaining forest, remaining forest and tractor tracks. Hydraulic conductivity measurements on saturated soil were conducted both on the control forest as well as on the logged plots, with no treatment distinction. The soil showed a low available water storage capacity: only 11 to 18% can be available to the plants, up to 1 meter depth. The temperature of the soil upper layers was influenced by logging, i. e., through the opening of the gaps, light reaches the soil more intensely in the center and edge of gaps, increasing temperatures in relation to the control and the remaining forest.