Impacts of land use and occupation in riparian zones on water quality and soil fertility: a study in the Antas River, Irati-PR, Brazil

Uncontrolled population growth and intensified human activities result in environmental impacts on water bodies and soils in Permanent Preservation Areas (PPA) found in riparian areas (RA). This study aimed to assess the water quality of the Antas River and the soil fertility of its PPA present in riparian areas, correlating the results with the land use and occupation in riparian areas. Land use and occupation mapping was conducted in the Antas River watershed, and subsequently, 14 sampling points were selected along the main river. Water samples were collected at these points and characterized for parameters of the water quality index (WQI). Soil samples from the riparian area at the sampling points were collected and fertility analyses were performed. The data indicate that vegetation in RA is essential for soil fertility, positively influencing organic material, phosphorus, calcium, and pH in CaCl2. The significant presence of native vegetation is associated with higher organic material in the soil, lower levels of aluminum, and better water quality indices. Conversely, urbanized areas with low organic material, high aluminum concentrations, and poor water quality show a direct relationship.