Analysis of the physico-chemical relationship between losses of water, soil and soil nutrients in the water of the Farinha River – MA

Brazil has a vast reserve of water resources, but pollution from various sources and the effects of climate change have triggered a crisis in this sector. The as-sessment of water quality indices plays a crucial role in monitoring and unders-tanding this issue, and the country has established its own standards and moni-toring requirements to guarantee water quality. In addition, the physical-chemical relationship plays a fundamental role in the conservation of both soil and water. In this context, a study was carried out in the Farinha river basin, located in Maranhão, in the Cerrado biome, over an area of 55,338.12 hecta-res. Data was collected at ten different points along the river during the rainy and dry seasons. A Van Dorn bottle was used to collect water samples at vari-ous depths, which were analysed for pH, dissolved oxygen, electrical conducti-vity and temperature. Nutrients such as potassium, calcium, magnesium, sodi-um, silicon, nitrate and total phosphorus were quantified using filtration and spectroscopy techniques. The data obtained was tabulated and subjected to analysis of variance, with the means analysed using the Tukey test. This study reveals significant seasonal variations in the physico-chemical parameters of the water in the Farinha River in Maranhão, impacting aquatic life and water quality. This highlights the importance of continuous monitoring and manage-ment of these resources.