The study on Water Quality from Paddy Field practicing : Case Study of Suphanburi Province

Abstract

The study area on water qualities from paddy field practicing was selected in Suphanburi Province where Paddy field was mostly practiced. The study was emphasized on the chemical residue in water resource from paddy field. Water samples were collected from Amphoe Bang Pla Ma which was identified to represent the area where heavy used of chemicals and from Amphoe Si Pra-chan to represent the least used of chemicals. The samples were undertaken from 4 sampling areas : main irrigation canal, division irrigation canal, paddy field and Tha Chin River totalling 9 sampling points. Sampling was done 2 times : before planting (in April) and during transplantation (in October). The water indics were concentrated on the amount of organochlorine insecticide and some physical properties. The study revealed that water qualities in water resource before paddy field practicing had much higher amount of dissolved oxygen and electricity conductivity than after paddy field practicing. Organochlorine insecticides were found much higher during paddy field practicing especially especially total DDT and Alpha – BHC evidenced in every sampling points. Those In some sampling points were higher than the standard of surface water (Division of Environmental Standard, 1991). The comparison of water quality of the 2 districts evidently revealed that the water resources in Amphoe Bang Pla Ma had more insecticide residues than those of Amphoe Si Pra-chan. However, dissolved oxygen (DO) had no significant difference but electric conductivity (EC) in Amphoe Sri Pra-chan had a little bit lower than Amphoe Bang Pla Ma.