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Abstract Tectonic rejuvenation has been widely described in ancient rifting areas of intraplate settings, despite extensive active tectonics being discontinued long ago. Various models have been invoked to justify such tectonic rejuvenation, suggesting that the long-term deformation in intraplate interiors may be more complex than once supposed. Inherited weakness zones, e.g., pre-existing faults are stress concentrators. However, not all weakness zones in plate interiors show tectonic rejuvenation and recognizing intraplate fault reactivation remains puzzling. Bedrock channels play an essential role in tectonically unstable landscapes and therefore they may unveil which pre-existing structures have been rejuvenated. Here we explore the Cinzas Catchment in order to investigate the interactions between tectonic rejuvenation, bedrock inheritance and geomorphic river signatures in an important Brazilian rifting feature, the Ponta Grossa Arch. We perform a geomorphic analysis combined with fieldwork, dating techniques and existing data to evaluate whether the geomorphic responses of the major rivers show perturbations related to the bedrock inheritance and post-rift rejuvenation. We also show that the interactions between river signatures and the bedrock fault zones are responses to post-rifting rejuvenation coupled with bedrock inheritance. This post-rifting rejuvenation is consistent with a mosaic of superimposed mechanisms which have been invoked by previous studies.

The pursuit for understanding the dynamics involved soil loss by erosion processes, aiming at its measurement and conservation management, is taking space in the scientific world due to socioeconomic and environmental problems resulting from this type of degradation. For that we are discussing the importance of considering the natural aspects what promote soil loss and agricultural practices. The study was conducted in two farms in the State of São Paulo-Brazil, located in the municipality of Getulina, intended for beef cattle, and the second in Veracruz, for the coffee production. The soil losses were estimated by monitoring plots with erosion pins, registering the monthly variations for a year. These records were compared with daily precipitation data and with the vegetation cover percentage present within the plots. Analyzing the results was identified the largest annual soil loss in Veracruz, estimated at 691 T/ha/year. This soil loss is associated with the greatest precipitation record in Veracruz, as well as with the largest vegetation cover percentage variation over the months, associated with the coffee plantation in formation, which results in a large exposed soil portion. In addition, and as conclusion, the morphological and textural features indicate a tendency to compaction, especially with intensive use of farm machines, with strong textural change, which helps with less porosity and permeability, and with a surface horizon cohesive, easily take by little runoff.

This paper uses the Physical Geography approach to analyze the environmental complexities of an area located in the coastal plain of the Serra do Mar. The quilombola territory (territory of quilombos inhabitants), from its historical, social and cultural formation, to contextualize the process of evolution of natural systems, the territorial conflict and the production of geographical space, focusing on the legal decision process for the State to recognize quilombola territory. The Quilombo da Fazenda, in Ubatuba, is located in an area overlapping the State Park of Serra do Mar. Technical, scientific and legal limitations hinder the definitive, official recognition of the quilombola territory. The research will contribute to resolve the technical impasse and generate social changes capable of promoting environmental justice in the region. Based on the methodological approach, it concluded that on the spots where historically the Quilombo da Fazenda community use the land, there are an positive influence emerge on the composition of forest fragments, i.e., increase in number of species and stability of erosive morphodynamic processes and gravitational mass. The combined dynamic among soil, earth surface and forest, results in physical and biotic conditions that can subsidize the analysis of environmental support capacity of the area, an essential required prerequisite for the State to recognize the quilombola territory. Using Ecodynamics criteria, namely geostatistical modeling combining susceptibility data of gravitational movements of mass, slope, and flood, with the occurrence of species and forest richness, the study classified three different environmental support capacity high, medium and low.