湖泊沉积物短时间反复扰动下悬浮物上生物有效磷的动态变化

以太湖梅梁湾、月亮湾的沉积物和上覆水为材料,研究了较短时间尺度和沉积物反复扰动条件下,悬浮物中不同形态生物有效磷数量分布的变化特征.结果表明,随着扰动次数的增加,上覆水中藻类可利用磷(AAP)占溶解态总磷(DTP)的百分比均有所降低.试验期间,悬浮物中弱吸附态磷(NH4Cl-P)、可被生物利用颗粒态磷(BAPP)占总磷(Tot-P)的百分比平均值分别增加了3.5%、37.3%(梅梁湾)和2.0%、50.7%(月亮湾).梅梁湾悬浮物上AAP含量及其占Tot-P的百分比随扰动次数增加而增加,月亮湾则恰好相反.扰动期间,悬浮物上BAPP含量始终大于NH4Cl-P和AAP之和,表明BAPP的80%是由NH4Cl-P和AAP组成的.这也暗示了,仅仅以悬浮物中NH4Cl-P、AAP来估算BAPP存在一定的不合理性.

Bioavailable Phosphorus on Suspended Solids of Lake Under Short-term and Repeated Sediment Disturbance

Variation of bioavailable phosphorus forms on suspended solids under short-term and repeated sediment disturbance was investigated, using sediments and overlying water from Meiliang Bay and Yueliang Bay. The results showed that the average percentage of algae available phosphorus (AAP) in the dissolved total phosphorus (DTP) decreased with the increase of disturbance number. The NH₄Cl-P and bioavailable particulate phosphorus (BAPP) on the suspended solids increased by 3.5%, 37.3% (Meiliang Bay) and 2.0%, 50.7% (Yueliang Bay), respectively. In addition, the AAP and its percentage of AAP in Tot-P on the suspended solids in Meiliang Bay increased with the increase of disturbance number. However, the case was the opposite for Yueliang Bay. During the disturbance, the BAPP was higher than the sum of NH₄Cl-P and AAP, indicating that the sum of NH₄Cl-P and AAP constituted 80% of BAPP. It also suggested that estimating the BAPP on the suspended solids using the sum of NH₄Cl-P and AAP is problematic.