Caracterização ambiental e da qualidade das águas de córregos em fragmentos de Mata Atlântica

Abstract

This dissertation is divided into two parts, the first being an environmental characterization carried out in May 2010, three first-order streams, named A, B and C, located on privately owned Forest Farm amid the typical vegetation of the Atlantic Forest biome, a rural area of the city of Juiz de Fora. Were selected in each stream three stretches (I, II, III) in which measures have been taken in rejoinder variables environmental, using the average value for data analysis. The particle size distribution and concentration of organic matter (OM) of sediment from each section were also analyzed. To evaluate the environmental conditions of streams and its surroundings used the Rapid Assessment Protocol (RAP). The waters of each section were compared with parameters established by CONAMA Resolution 357/2005 and CETESB, 2007. The ANOVA parametric test (one way) was used to test for significant differences in the values of environmental variables and RAP among streams. To check the similarity between the sections of each stream and between the three streams studied used the cluster analysis (UPGMA) by Euclidean distance. Principal Component Analysis (PCA) was used to determine abiotic variables which best explained the variability of the data and its correlation with the stretches. Overall environmental variables and RAP presented comply with the terms of reference for classification of water quality, showing that the environments are preserved, are similar and reflect the relationship with the environment. The second part aimed to evaluate the water quality of the main stream of the sub-basin Quinces. The study was conducted in May 2011, in six parts, from upstream to downstream in the longitudinal profile of the stream, located in the municipality of Finchley, MG (stretches I and II) and Juiz de Fora-MG (stretches III, IV, V and VI). We obtained data on physiographic parameters and environmental variables in the sub-basin and the collected benthic macroinvertebrates, which were separated into morphotypes, to help assess the quality of the environment through the Sequential Comparison Index (SCI). Also used granulometric composition of sediment and concentration of organic matter, implementation of PAR and compared with references of CONAMA 357/2005 and CETESB, 2007. Were also estimated potential pollution (diffuse pollution) due to use classes and land cover and potential polluter by individuals (point source pollution) according to the contribution by loads of nutrients such as phosphorus (P) and nitrogen (N). The same analyzes of the data used in the first part were addressed on Monday, except PCA. Was added to the Sequential Comparison Index (SCI) and applied a linear regression to assess correlations between variables total nitrogen (Nt), total phosphorus (Pt) with SCI. The results showed that the variables were generally in accordance with the terms of reference, being only Nt and Pt concentrations inconsistent with these terms, probably due to the use and occupation of the land around the passages.