Geospatial model of organophosphate insecticide residues in shallot land in Wanasari Sub-district, Brebes Regency, Central Java Province, Indonesia

Abstract

Organophosphates are a group of chemicals that are still allowed to be used in Indonesia and much preferred by most farmers. Excessive usage of organophosphate is expected to contaminate the soil, water, plants, the environment and humans. This research was aimed to create the geospatial models of organophosphate insecticide residues which consist of Chlorpyrifos, Diazinon and Profenofos on farms of shallots production centers. The research was performed in the field of shallots production agriculture in Wanasari sub-district, Brebes Regency in March-June 2020. The extraction of multiresidue pesticides method used was the QuECheRS and the measurement of residues used the 2014 GC Shimadzu with Electron Capture Detector (ECD) which was carried out in the IAERI Laboratory. Meanwhile, the geospatial modeling of organophosphate insecticide residues was done by using the Spline Interpolation method in ArcGIS 10.4, which was carried out in Diponegoro University's CoREM laboratory. The analysis of soil samples taken from 44 sampling points showed that the Organophosphate insecticide Chlorpyrifos was at the level of