沉积物-水系统中氮磷变化与上覆水对藻类生长的影响

研究了灭菌、抑制剂添加和磷添加对沉积物-水模拟系统中氮磷转化的影响,并利用试验后的上覆水培养四尾栅藻.结果表明,灭菌增大了系统平衡时上覆水的总磷(TP)浓度,对系统中氮的影响不大; 添加抑制剂组与对照组沉积物-水模拟系统的TP、溶解性总磷(DTP)和总氮(TN)的浓度接近,但抑制剂组的NO^-₃-N含量为19.2 mg·L^-1,明显高于对照组;沉积物对添加的磷有强烈的吸附作用,导致系统平衡时上覆水TP的浓度降低.灭菌组上覆水的藻类生物量高于对照组,主要是因为灭菌导致上覆水TP浓度高于对照组;抑制剂组的最高藻类生物量(224.5×10⁴个·L^-1)远远超过对照组(26×10⁴个·L^-1),且为其它2组试验(灭菌组22.5×10⁴个·L^-1和磷添加组38.5×10⁴个·L^-1)的5～10倍,抑制剂的添加抑制了沉积物-水模拟系统中微生物对某些元素的利用,而这些元素对藻类生长起重要作用;磷添加对试验初藻类生长无明显影响,随着试验进行,磷添加组的藻类适应生长环境,迅速增长,生物量远远超过对照组.灭菌和添加抑制剂组生物可利用磷的增加是由于藻类生物量的增加,而导致了不稳定态的有机磷的增加.

Variation of Nitrogen and Phosphorus Concentration in Water-Sediment System and Influence of Overlying Water on the Algae Growth

The effect of biosidal treatment of initial sediment, addition of inhibitor and addition of phosphorus on the transform of nitrogen and phosphorus in the sediment-water simulative system were studied. S. quadricaudain was cultured in overlying waters took from the above experiment sets when the above experiment completed. The result indicated that, biosidal treatment enhanced the concentration of TP while there was no obvious effect on N. The TP, DTP and TN concentrations were closely between inhibitor addition set and the control set in the sediment-water simulative system but the content of NO3(-)-N of the set with inhibitor addition reached 19.2 mg x L(-1), which was much higher than that of the control set. The sediment significantly adsorbed the P added to the system, and the content of TP decreased when the system reached balance. Algae biomass of the biosidal treatment set was higher than that of the control set, and the main cause was sterilizer leaded to higher concentration of TP of the biosidal treatment set. The highest Algae biomass of the group with inhibitor (224.5 x 10(4) unit x L(-1)) was much higher than that of the control set (26 x 10(4) unit x L(-1)), and that was 5-10 times than that of other sets (sterilized set 22.5 x 10(4) unit x L(-1), set with P added 38.5 x 10(4) uni x L(-1)). Inhibitor restrained the microorganism from using some nutrition which was important to alga's growth. At the beginning, the addition of P had no remarkable effect on the alga growth, but along with the experiment, the alga of the P addition set adapted to the environment and algae biomass exceed that of the control set. The increase of biological bioavailable phosphorus of sediment in biosidal treatment set and addition of inhibitor sets were caused by the increase of algae biomass and thus the increase of liable organic phosphorus.