No abstract

Butia palm forests are considered unique due to their aesthetic value, high biodiversity level and historical, archaeological and cultural value. The lack of regeneration of butia palms caused by cattle overgrazing and natural grasslands replacement by agriculture endangers these palm forests. The aim of this work is to provide information for the proposal of a conservation area in this rural landscape within the framework of sustainable development. This work was developed within the context of a Geographic Information System with thematic information on palm forest density levels, soils, land use aptitude and rural registers. Field surveys were conducted to record the presence of plant species and genetic resources in different vegetation units. The main category of soil cover was natural grasslands, followed by native forests, wetlands and palm forests. Palm forests grow mainly on soil units with poor to rather poor drainage and on arable or non-arable lands under special conditions. We identified 212 farms where the palm forest is found, a high diversity of vegetation units, the presence of 302 native taxa of plants and a significant number of plant genetic resources for various uses. For the designation of a conservation area, we propose 20 priority farms that will ensure that palm forests are well represented regarding ecosystem diversity. We consider the creation of a Protected Landscape, a State Park or a GIAHS to be the best alternatives so as to protect this unique multifunctional landscape.

The Ribeira Valley region (State of Sao Paulo, Brazil) hosts the largest Brazilian Atlantic forest reserve. The region was an important mineral district during the '60s, from where several tons of lead and other metals were exploited. Residual materials produced by the mining are diffused in the environment until today. The area also encompasses a regional arsenium anomaly associated with unexplored gold deposits. The population presently living in this region performs basic farming activities, from which most of their food is yielded. These features coupled together imply in a complex relationship between natural and anthropogenic factors that are likely to affect the life and health of the local communities. The aim of this paper is to apply digital data integration techniques for environmental risk assessment in the Ribeira Valley using environmental geochemistry. Geochemical, digital elevation and remote sensing data (Landsat Thematic Mapper) were merged and analyzed using a geographical information system. The assumed model considered environmental mobilization through erosion and anomalous As-Pb areas. Data were analyzed through Boolean and fuzzy logic techniques. Fuzzy logic proved superior in this case study as it allowed not only the detection but also the distinction between low, moderate and high environmental risk areas.