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This study presents the results of the soil hydraulic characterization performed under three land covers, namely pasture, 9-year-old restored forest, and remnant forest, in the Brazilian Atlantic Forest. Two types of infiltration tests were performed, namely tension (Mini-Disk Infiltrometer, MDI) and ponding (Beerkan) tests. MDI and Beerkan tests provided complementary information, highlighting a clear increase of the hydraulic conductivity, especially at the remnant forest plots, when moving from near-saturated to saturated conditions. In addition, measuring the unsaturated soil hydraulic conductivity with different water pressure heads allowed the estimation of the macroscopic capillary length in the field. This approach, in conjunction with Beerkan measurements, allowed the design better estimates of the saturated soil hydraulic conductivity under challenging field conditions, such as soil water repellency (SWR). This research also reports, for the first time, evidence of SWR in the Atlantic Forest, which affected the early stage of the infiltration process with more frequency in the remnant forest.

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.

Knowledge of the hydraulic properties of the soil is of crucial importance to an understanding of the interactions between vegetation, soil and water. There is little information available about the hydraulic properties of Podzol soils found in tropical regions. The aim of this study was to present the soil morphology and hydraulic properties of a toposequence situated in a permanent plot at the Ilha do Cardoso State Park (Cananéia, SP, Brazil). Ultradetailed soil maps were used to define a toposequence inside the permanent plot. Five profiles, representing the main types of soil, were opened along the toposequence, in which Podzols are dominant. The levels of bulk density, sand content, porosity and permeability in these soils were all high. Consequently, these soils have a high level of hydraulic conductivity with low water retention. This behavior undergoes an alteration in the Bh and Bs horizons due to the accumulation of organic and metallic compounds and a changing structure that modifies the pore distribution. Furthermore, the characterization of the hydro-physical functioning of soils in natural environments is an important source of encouragement to further investigative study of soil water dynamics and its relationship to the native vegetation.

With the rapid technological development in the agricultural sector experiencing in recent decades, the process of degradation of soil cover has intensified exponentially. The municipality of São Carlos do Ivaí - PR, in which this study was developed, is currently with its farmland cultivated with sugarcane, where is developed a technified management, dependent on the use of large amount of large agricultural machinery. It was evaluated in this study as the Latossolo formed from the decomposition of rock Caiuá Formation and Latossolo formed from the decomposition of the rock of the Serra Geral Formation are reacting to the use and employe management. To achieve these goals, it was made use of the methodology of Cultural Profile and physical and chemical analyzes of the soil, using the standards contained in the Manual of soil analysis methods (EMBRAPA 1997). The results indicates that the eutroferric RED OXISOL typical clayey, originated from the decomposition of rocks of the Serra Geral Formation, had better conditions in their physical properties compared to the dystrophic RED OXISOL medium texture, originated from the decomposition of rock formation Caiuá. As regards, the bulk density the RED OXISOL eutroferric typical clayey had the lowest values compared to dystrophic RED OXISOL medium texture, providing the highest porosity rates and consequently better able to hydraulic conductivity under natural conditions. Based on the results, we can point out that the Oxisol clay texture, when subjected to intensive agricultural management, has greater variations in their physical and hydraulic properties compared to medium texture Oxisol. Faced with the confrontation of values obtained for the main physical properties of the soil, it was observed that in the medium textured Latosol, the effect of compression is less than the Oxisol clayey. Although, the Oxisol clayey count on better conditions of physical properties when compared to medium texture Oxisol, the agricultural management changes over their values. Therefore, it should be noted with extreme attention to soil moisture condition s at the time of the management of sugarcane operations impacted as little as possible the soil volumes, thus maintaining your next natural conditions. Com o rápido desenvolvimento tecnológico no setor agrícola experimentado nas últimas décadas, o processo de degradação da cobertura pedológica têm se intensificado exponencialmente. O município de São Carlos do Ivaí - PR, onde foi desenvolvido esse estudo, encontra-se atualmente com suas terras agrícolas cultivadas com a cana-de-açúcar, onde é desenvolvido um manejo tecnificado dependente do emprego de grande quantidade de máquinas agrícolas de grande porte. Avaliou-se nesse estudo, como o Latossolo formado a partir da decomposição da rocha da Formação Caiuá, e o Latossolo formado a partir da decomposição da rocha da Formação Serra Geral estão reagindo ao uso e manejo empregado. Para atingir esses objetivos, fez-se uso da metodologia do Perfil Cultural e análises físicas e químicas do solo, empregando as normas contidas no Manual de métodos de análise de solo (EMBRAPA 1997). Os resultados obtidos indicam que o LATOSSOLO VERMELHO eutroférrico típico textura argilosa, originado a partir da decomposição das rochas da Formação Serra Geral, contou com melhores condições em suas propriedades físicas se comparado ao LATOSSOLO VERMELHO distrófico típico textura média, originado a partir da decomposição da rocha da Formação Caiuá. No que se refere à densidade do solo, o LATOSSOLO VERMELHO eutroférrico típico textura argilosa contou com os valores mais baixos se comparado ao LATOSSOLO VERMELHO distrófico típico textura média, proporcionando os maiores índices de porosidade e consequentemente melhores condições de condutividade hidráulica sob condições naturais. Com base nos resultados, pode-se apontar que o Latossolo textura argilosa, quando submetido ao manejo agrícola intensivo, apresenta maiores variações em suas propriedades físico-hídricas se comparado ao Latossolo textura média. Diante da confrontação dos valores obtidos para as principais propriedades físicas do solo, observa-se que no Latossolo textura média o efeito da compactação é menor do que no Latossolo textura argilosa. Embora o Latossolo textura argilosa conte com melhores condições de propriedades físicas se comparado ao Latossolo textura média, o manejo agrícola altera mais seus valores. Sendo assim, deve ser observado com extrema atenção às condições de umidade de solo no momento das operações do manejo da cana-de-açúcar, impactando o mínimo possível os volumes de solo e mantendo assim suas condições próximas do natural. 126 f