静态条件下底泥中不同形态磷的变化规律

Variation of different phosphorus forms in the sediment under static state

上覆水中磷被结合到底泥中时,不同形态磷的数量将会改变,由此导致磷的释放能力和生物有效性被显著改变。以富营养化河道上覆水和底泥为材料,考察了静态条件下,底泥中不同形态磷的变化规律及其对磷的生物有效性的影响。结果表明,潜在活性磷(PMP)含量显著增加,NH4Cl-P、BD-P、NaOH-nrP分别增加了297.68%、10.73%、30.49%。难释放态磷则基本保持不变。潜在活性磷对生物有效磷的形成具有显著的影响,4种生物有效磷中的3种(WSP、Olsen-P、AAP)均与其在α<0.01水平上显著正相关,并且其对AAP形成的影响最为显著。因此推测,静态条件下,当上覆水中磷向底泥迁移时,首先会形成潜在活性磷和生物有效磷。

When phosphorus in overlying water was incorporated into the sediments, the amount of different phosphorus forms would be changed, resulting that the release and bioavailability of sedimentary phosphorus were evidently changed. A lab-scale study was carried out to investigate the variation of different phosphorus forms in the sediment under static state and the effect of the change of phosphorus forms on the bioavailability of sedimentary phosphorus, using overlying water and sediments from the eutrophic river course as materials. The results show that the content of potentially mobile phosphorus（PMP） increased obviously. The contents of NH4Cl-P, BD-P, NaOH-nrP increased by 297.68%, 10.73%, 30.49%, respectively, compared with the initial state. However, the refractory forms kept relatively constant. The content of PMP had significant impact on the formation of bioavailable phosphorus（BAP）. Remarkable positive correlation was shown between WSP, Olsen-P, AAP and PMP above the level of α〈0.01. Moreover, PMP had more significant impact on the formation of AAP than on that of other bioavailable forms. It is suggested that phosphorus in migration from overlying water to the sediments under static state could be transformed into PMP and BAP at the first step.