SUMMARYThis study had the purpose of evaluating the effects of two management types of sugarcane: harvesting of burnt cane (BCH) and mechanized harvesting of unburnt green cane (MCH), on some soil physical properties of a dystrophic Rhodic Haplustox. The data were then compared with results for the same soil type under native forest. A completely randomized design was used, with three treatments and 20 replications. The following characteristics were determined: organic matter, aggregate stability, soil bulk density, and porosity at depths of 0-0.20 m and soil penetration resistance. After 15 years of cultivation, there were some alterations in the soil under cane burnt before harvesting, evidenced by a drop in the weighted average diameter of stable aggregates in water and increased soil bulk density. Significant changes were also detected in total porosity and pore distribution under both harvesting systems. Critical values for penetration resistance were observed in the area under mechanized sugar cane harvesting, with a value of 4.5 MPa in the 40-55 cm layer. This value is considered high and could indicate compaction and restriction of root growth. Soil properties under the green cane (unburned) management system were closest to those of the soil under native forest.Index terms: Saccharum officinarum, soil bulk density, porosity, soil penetration resistance, soil aggregate stability.(

Research related to geodiversity aim at valuing abiotic aspects as inseparable components of natural heritage and, thus, as well as biodiversity, must be understood and valued through the ordering of their use and geoconservation. Geodiversity studies are developed based on several approaches, from the broadest ones, which contemplate the measurement of abiotic elements fully, to those that assess geoheritage through geodiversity values. The present research follows the broader approach of evaluating and analysing the entire geodiversity, applying the measurement of abiotic elements without their valuation, and spatialising areas with a greater and lesser density of the selected elements related in this research lithology, relief, and soil. For this purpose, bases produced by systematic surveys of Brazilian research institutions were used. As a result, the mapping of the subindexes obtained pointing from the division into 5 classes, the areas which present greater and lesser diversity of each element, as well as the synthesis map for the indexes of geodiversity elements in Brazil, considering the three elements selected for this mapping. The analysis of the indexes' spatialisation was carried out from a descriptive and genetic perspective, aiming to explain the causes of the distribution of the abiotic elements in the Brazilian territory, providing subindexes for studies in the scope of environmental services, nature, and territory conservation planning. A spatial analysis was also carried out between the Geodiversity Index Map and the Brazilian conservation units and the areas where geopark projects are being developed.

A paisagem é considerada um dos objetos-chave da geografia. O solo se mostra como integrador dos diferentes elementos que a compõem, seu estudo é fundamental para desvendar os processos que atuam modificando as rochas, os solos e as formas de relevo. O objetivo deste artigo é analisar, sob um enfoque epistemológico e metodológico, a Pedologia como ramo natural da Geografia Física, em função de sua abordagem multifatorial. Partimos de uma discussão a respeito da paisagem como objeto de estudo geográfico, dos problemas que envolvem as aproximações multiescalares no espaço

This research investigates the pedological cover to understand genetic processes at work in the formation and evolution of closed depressions in the Três Cantos compartment. The study area is located in the municipality Maracaí-SP (Brazil), at the interfluve between Anhumas and Capivara rivers, both tributaries of the Paranapanema River. The area has closed depressions in the top of local surface, with red-yellow and red soils and iron crust. To achieve our goal we evaluated two toposequences in the Mandacaru depression, as well as regional and local factors that could contribute to the formation and evolution of depressions. The procedures adopted for this research were based on the Structural Analysis of the Pedologic Coverage, proposed by Boulet et al. (1982). The results showed that the pedological processes that dominate are latosolization, hydromorphy and illuviation. The latosolization transforms the iron crust into Latosol in the Brazilian System of Soil Classification (Ferrasols-FAO, 2006). The hydromorphy that attacks the iron crust and Bw horizonsresulting in a block structure when dry, and massive when wetcombined with the illuviation process that transforms the horizons A and Bt into E result in Argisol in the Brazilian System of Soil Classification (Lixisols-FAO, 2006). The latosolization process was the first to transform the iron crust, followed by wet conditions, transforming the iron crust and latosols due to hydromorphy action; consequently, the plateau was deformed. Hydromorphy, therefore, was responsible for initiating depression formation and subsequently the illuviation process contributed to it. Currently these two processes act deepening and widening the depressions. The formation of depressions is related to the geological structure, and these depressions are the initial stage of the area's drainage system, as may be observed in areas where the depressions have been opened, and where the soils are not yet adjusted to the new form of the slope.