Indicação de influências antrópicas em ambientes aquáticos do oeste do paraná por meio da especiação da matéria orgânica dissolvida

Abstract

The current development model has brought about a significant imbalance in the functioning of the metabolism of water bodies, mainly due to the introduction of anthropogenic organic material in the environment. Therefore, studies seeking to detect these liabilities are necessary to foster strategic decisions. For that, several methodologies can be used, among them molecular fluorescence and visible ultraviolet (UV-vis) spectroscopy, to detect and determine the source and complexity of the organic matter, acting as indicators of anthropic pressures. The study aims to use molecular fluorescence and spectroscopy in the UV-vis region to evaluate and estimate the anthropogenic influence points in aquatic environments in western Paraná through the speciation of dissolved organic matter. Sampling was carried out in 36 points, distributed in three lotic and one lentic environment, from February to November 2019 (four samplings), resulting in 107 variables and 139 sampled points. Different parameters associated with the source, nature, and complexity of organic matter were used; besides, physical, chemical, and biological parameters allowed an understanding of the dynamics of the environments. Also, the Principal Component Analysis (PCA)/Factor Analysis (FA) technique was used, which allowed the explanation of 71.91% of the variability of the water quality data, and spectroscopic techniques largely explain the data variability with high factor loadings. The main factors influencing the data variability were the complexity of the organic matter, nutrient content, and rainfall, which highlighted the sources of organic matter and a high indication of the anthropogenic pressures linked to it. It was possible to observe the isolation of points with the inflow of domestic and industrial effluents treated as one of the leading environmental impacts impacting the studied environments and the management of arable areas as one of the primary means of allochthonous enrichment in the rainy season from surface runoff and concentration of labile compounds in the dry season. Therefore, it is possible to conclude that spectroscopic techniques can successfully indicate the anthropogenic pressures observed in the aquatic environments of western Paraná