Environmental Impact of Agrochemical uses on the Island’s Agricultural Production Area in Maranhão, Brazil
Agriculture is the foundation of society, provided with its food needs for over ten thousand years. The use of pesticides in Brazil and the world has grown exponentially in recent decades. The objective of this study was assessment the use of agrochemicals and their environmental impact on agricultural production of the Island of Maranhão. The study area is located in Paço do Lumiar, Maranhão, Brazil. Soil samples were collected from agricultural land during the wet season (between the months of February and May) and dry season (between the months of September and October) seasons of 2018. We analyzed the soil Physico-Chemical characteristics, organic matter, organic carbon, moisture content, granulometry, pH, nutrient concentrations (nitrate and nitrite, total phosphorus), adsorption isotherms, and microorganisms in the Environmental Sciences Laboratory of the University Ceuma. The results of the physical and chemical analysis of the soil samples suggest the soils could be classified as sandy and silty to clay. There is a concern that the levels of nitrate, nitrite, and phosphorus, especially in rural areas, as well as runoff occurring during production increase due to the use of fertilizers. Microbiological examination showed the presence of gram-negative bacteria of the genus, Pseudomonas and Escherichia coli. Isotherm models show Kf values of <10 have a low adsorption capacity for the pesticide malathion, suggesting that the soil has the potential to increase contaminant availability to plants and contaminate the water table; however, other soil factors and climatic conditions should be evaluated when evaluating the behavior of pesticides in soil.
