| dc.description.abstract | The application of pesticides by shallot fanners in Brebes generally was very intensive, either dosage or the frequency of application. The use of certain pesticide intensively in the agriculture has left a residue of pesticide in the plant and polluted the environment especially in the soil, surface water and ground water. In the environmental pollution, the persistency of active substance of pesticide plays very important role. This research was aimed to investigate the residue concentration of pesticide which belongs to organophosphate group in Alluvial soils after shallot cultivation in Brebes, Central Java. One of such pesticide is Dursban which has Chlorpyrifos as active substance. Another objective of this research was to study the pattern of relationship between soil characteristics and the residue of pesticide in Alluvial soils. I The results of the research showed that all soils in the study area contained high concentration of Chlorpyrifos residue, ranged between 0.39 - 0.72 mg/kg soil. Simple regression analysis showed there was a significant correlation between total Dursban application and total land area with Chlorpyrifos residue in the soil (r2= 0.76 and r= 0.70). This indicated that the bigger the area was used, and so the use of the Dursban, therefore caused the high concentration of Chlorpyrifos resiJue in the soil. There was no relationship between pH, C-org and Clay content with the Chlorpyrifos residue in the soil (r2= 0.24; r= 0.37; and r2= 0.20). Although there was no significant correlation, however, there was a tendency that increasing soil pH will cause decreasing of the Chlorpyrifos residue in the soil. High soil pH will cause the degradation of Chlorpyrifos by action of hydrolysis. Organic matter and clay content also tend to affect the concentration of Chlorpyrifos residue in the soil. High content of organic matter will suppress the volatilization of the pesticide and high clay content play in the absorption process | id |
