Study of nitrate and nitrite in thale sap songkla: Water quality of thale sap songkla I

Abstract

A study of nitrate and nitrite in Thale Sap Songkla was carried out during 1985–1988. Water samples were collected every month and analysed by spectrophotometry using 1) Brucine method and 2) cadmium reduction methods.

The results from these studies show that the nitrate concentrations were in the range of 0.001–0.069 mg/L during 1985–1986, 0.020–0–705 mg/L during 1986–1987, and 0.216–0–791 mg/L during 1987–1988. In the dry season the concentrations of nitrate and nitrite were higher than those in the wet season on every stations.

The concentration of nitrate and nitrite were high at the stations near the outlet of small canal that passes through the community areas (townn/city).

The overall results indicated that the nitrate and nitrite increased significantly between 1985 to 1988.

Key words:

• Brucine method
• Cadmium reduction column
• Nutrient