Abstract:

Based on monitoring data of pollutants in different seasons of the 11 spots in Minjiang River from 2007 to 2008, this paper preliminarily studied the seasonal changes of surface water. The results showed indicators of organic pollution of surface water varied with the season. The concentration of COD in July and November were highest through the year, and ranged from 5.0 mg.L-1to 28.0 mg.L-1during this year. The concentration of NH+4-N in January and March were highest, and ranged from 0.18 mg.L-1to 2.97 mg.L-1 during the year. The concentration of TN and the concentration of NO-2-N in November were highest. The concentrations of TN ranged from 0.81 mg.L-1 to 3.23 mg.L-1 and the concentrations of NO-2-N ranged from 0.01 mg.L-1 to 0.15mg.L-1. The concentrations of TP were highest in January and November. But the concentration of COD, NH+4-N and NO-2-N in September were lowest. Moreover, there are the very significant positive correlation Between COD ， NH+4-N ，NO-2-N and TN, NH+4-N and TP. Generally, Minjiang water was easily polluted in winter and spring, followed in autumn.