Path modelling analysis of pollution sources and environmental consequences in river basins

Abstract

The Portuguese Index of Macroinvertebrates is used as a pollution index in the study of surface water in Portugal. From an environmental perspective, it is necessary to determine the pollution sources affecting surface water. Not only direct discharges of industrial and urban effluents are the cause; possibly the combination of other pollutions sources could result in ecological loss. To comprehend all the cause and effect relationships between pollution sources, water contamination and ecological integrity, it is necessary to apply complex models and possibly apply the use of thorough statistical tools. Structural Equation Modelling (SEM) has been used in the social sciences for a long time. Due to the present environmental concern and awareness of the phenomenon's complexity, SEM was used for environmental studies. In this paper are present SEM-PLS models that are applied to collected data from two different river basins, that of the Ave and the Sabor, in order to understand which are their main pollution sources and which contaminants are restraining biodiversity. The applied models from each basin reproduced different realities, as expected, since the river Ave has has the notorious impact of industry, while the Sabor basin has a higher level of water quality.