Diagnóstico ambiental nas áreas de preservação permanente do córrego Lajeado, Uberlândia-MG

Abstract

Veredas and gallery forests are riparian ecosystems, present in the Cerrado bioma, essential for the conservation of water resources and environmental balance. Even though they are legally protected as Permanent Preservation Areas (APPs), the environments comprised by these phytophysiognomies suffer constant negative environmental impacts resulting from land use. For a more effective conservation of the areas originally covered by veredas and by gallery forests, it is necessary to know them better. In this context, environmental diagnoses represent an important tool, as they allow investigating compliance with legal standards relating to the protected areas and also their environmental quality. From this perspective, the aim of this study was to carry out an environmental diagnosis in the APPs of Lajeado stream, in Uberlândia-MG. For this purpose, land cover and land use maps were produced comparing the following satellite image classification techniques: Maximum Likelihood (MaxVer) and segmentation of the Normalized Difference Vegetation Index (NDVI) values. At distributed points in three stretchs of the study area, the main negative environmental impacts were assessed by applying a Rapid Assessment Protocol (RAP). Field visits were carried out in February and March 2020 for definition of land cover and land use classes and for application of the PAR. According to the environmental diagnosis carried out, the two classification methods employed had satisfactory results, however the classification by MaxVer had better performance than the classification by segmentation of the NDVI values. The types of land cover and land use in conflict with federal and municipal environmental legislation were: burning, building, exposed soil and pasture, the latter being the conflicting use that covered the highest percentage of APPs in the analysed years. Through the assessment of negative environmental impacts, it was found that the Stretch 2 was the most impacted the segment in the APPs and the exotic vegetation, the solid waste and the sediments were the most frequent environmental impacts. Six priority points were identified for environmental recovery and one of the measures suggested to improve the environmental conditions of the APPs was the implementation of a linear park along the entire length of the stream. In view of the above, this research enabled to obtaining information on the irregularities and on the environmental quality of the legally protected areas of Lajeado stream, as well the presentation of measures for the environmental recovery of these areas, providing subsidies for the elaboration and for the execution of environmental studies and projects for a more effective preservation of the riparian ecosystems.