三峡水库蓄水期间香溪河库湾营养盐动态特征研究

2007年9-10月在三峡水库蓄水期间对香溪河库湾进行持续监测,并对其主要营养因子的动态特征进行了比较分析.结果表明;蓄水初期,香溪河库湾营养盐分布差异很大;蓄水完成后.香溪河库湾营养盐含量和长江趋于一致.香溪河库湾中TP含量由0.072 mg/L下降到O.066 mg/L,P04-P由0.032 mg/L升高到0.047 mg/L;TN含量略有升高,由0.785 mg/L升至0.817 mg/L,其中NO3-N占TN的百分比从66%增加到87%;D-Si浓度升高了约1.5倍.在3个控制断面,底层TP,PO4-P和D-Si含量大于表层,N在深度方向上没有明显规律.营养盐结构方面,Si/N＞1,Si/P＞10,有22%的N/P大于22,56%的介于10-22,22%的小于10.

Nutrients Dynamics in Xiangxi Bay During the Impounding of Three Gorges Reservoir

Xiangxi bay was continuously monitored during the impounding of Three Gorges Reservoir from September to October, 2007, the dynamics of main nutritional factors was analyzed. The results show that: the nutrients distribution of the Xiangxi bay shows great variations in the initial stage of the impounding; the nutrients content of Xiangxi bay is close to that of Yangtze River after the impounding; TP is dropped from 0.072 mg/L to 0.066 mg/L and PO4-P is increased from 0.032 mg/L to 0.047 mg/L; TN is increased from 0.785 mg/L to 0.817 mg/L and the percentage of NO3-N is increased from 66% to 87%; D-Si is increased by about 1.5 times. In the three control sections, TP, PO4-P and D-Si are greater in the bottom than on the surface. There is no apparent regularity in the N content. Nutrient structure: Si / N>1, Si/P>10, 22% of the N/P are greater than 22, 56% are between 10 and 22, 22% are less than 10.