Proposições para o gerenciamento do uso de agrotóxicos utilizados na bacia hidrográfica do Natuba, Vitória de Santo Antão, Pernambuco

Abstract

Environmental contamination by agrochemicals has been increasingly addressed by several authors in the literature and discussed by civil society, because of the way in which negative externalities in all environmental matrices are being felt. The present study aimed to propose measures of environmental management in the use of pesticides with a focus on water resources for the subbasin of the lower Natuba river, in Vitória de Santo Antão - PE. In order to do so, we used indexes that are designed to evaluate the ability of a given pesticidal active ingredient to leach or be transported into the environment, namely: Groundwater Screening Index (GSI), Groundwater Ubiquity Score (GUS), Relative Leaching Potential Index (LPA), Leaching Index (LEACH), Environmental Protection Agency criteria (EPA), California Department of Food and Agriculture criteria (CDFA), GOSS method and Water Contamination Risk Assessment (ARCA). Data from mathematical models for environmental management at the river basin level were then used. It was adapted a methodology for the management of contaminated areas focusing on the Natuba region in relation to environmental contamination by pesticides. The GSI, GUS, LIX, LEACH and RLPI indexes have been statistically shown to have similar values by means of the analysis of variances. The ARCA model adhered very well to the present research, showing results based on the specific characteristics of the region, fact that highlighted it in relation to the others. In general, when comparing the frameworks of each of the active principles picloram, hexazinone, thiamethoxam, imidacloprido, dicloreto de paraquate, diuron, paraquate, tebuconazole, linurom. were highlighted by the environmental hazard. The situation described in this paper exposes the need for a more rational use of pesticides in the locality of Natuba. Some changes must be made, among them: better law enforcement of 7802 of 1989, replacement of the cultivation site (which is located very close to the river) in order to comply with the provisions of the Forest Code in relation to the protection of riparian forests , modification in the matrix of agrochemicals used, respect to the times of application, prescription of agronomic prescription, in addition to the proper disposal of the empty containers of pesticides.