Using the single variable laboratory experiment

the wetland sediment in tidal flats areas of Min river estuary were collected to research the effect of pH on the nitrification

denitrification and mineralization processes of the nitrogen (the pH conditions were setting at 2.5

3.5

4.5

5.5

6.5

respectively). The results suggested that: In the nitrification process

lower pH (the pH was 2.5) showed the obvious inhibition on the nitrification activity

however

at other pH conditions

the influence on the nitrification rate of the sediment varied little. Which indicated that the number and the activity of the nitrifying bacteria were typical limited under the strong acid surrounding. In the denitrification process

the denitrification rate of the sediment decreased with time but the denitrification activity increased. Besides

the strong acid condition (the pH was 2.5) in some degree had inhibitory effect on the denitrification activity. Results indicated that denitrifying bacteria in the sediment was not active or the acid resistance bacteria was rare under strong acid condition. Finally

mineralization of the nitrogen was researched and no universal?rule was found between the pH and the mineralization rate

which showed that the pH had no direct effect on the mineralization process of sediment in the wetland.