Persistence of Cypermethrin, Deltamethrin and Endosulfan in an Oil Palm Agroecosystem
A study on the persistence of cypermethrin, deltamethrin and endosulfan in an oil palm agroecosystem was conducted at a Sime Darby estate in Sungai Buloh, Selangor. Three experimental plots in the estate were sprayed with cypermethrin, deltamethrin and endosulfan, respectively. The insecticides w...
| Autor principal: | |
|---|---|
| Formato: | Tese |
| Idioma: | English English |
| Publicado em: |
2002
|
| Assuntos: | |
| Acesso em linha: | http://psasir.upm.edu.my/id/eprint/10590/1/FP_2002_14.pdf |
| Resumo: | A study on the persistence of cypermethrin, deltamethrin and endosulfan in an oil palm
agroecosystem was conducted at a Sime Darby estate in Sungai Buloh, Selangor. Three
experimental plots in the estate were sprayed with cypermethrin, deltamethrin and
endosulfan, respectively. The insecticides were sprayed using a motorized mist blower at
the manufacturer's recommended dosage and double the recommended dosage. The
application was conducted in triplicate plots. Composite soil samples were collected
from each replicate plot at 0-10, 10-20, 20-30, 30-40 and 40-50 em depth. Palm fronds
were randomly harvested from the plots and water samples were collected from the
adjacent streams and drains along the plots. The insecticide residues in soil, water and
palm leaves were monitored at 1, 3, 7, 14, 30, 60 and 90 days after treatment.
Analytical methods for endosulfan, cypennethrin and deltamethrin residues were
evaluated and good recoveries were observed for the matrices examined. A gas
chromatograph equipped with an electron capture detector was used to quantify the
pesticide concentrations in the extracts.
Endosulfan was more persistent than deltamethrin and cypennethrin in the soil, with halflives
of 38, 5 and 2 days, respectively. The corresponding values for palm leaf were 9, 4
and 6 days. None of the insecticides studied was found leached beyond 10 cm of the soil
profile. Residue concentrations of the insecticides in soil and palm leaf were in the .range
of 0.001 to 0.l9 mg/kg and 0.001 to 2.40 mg/kg respectively. Surface runoff of the
insecticides however, was not evident in the agroecosystem as no residues were detected
in the surface waters from adjacent drains and streams.
The usefulness of two computer models, VARLEACH and PERSIST in predicting the
fate of the insecticides in oil palm agroecosystem was assessed by comparing the field
data with predicted data. Predictions with VARLEACH gave better agreement with
observed insecticides residues than PERSIST. VARLEACH predicted cypennethrin,
de1tamethrin and endosulfan did not leach beyond 10 cm of the soil profile, which was in
agreement with the field observation. |
|---|