| 作者： |
Feng, Weiying; Zhu, Yuanrong; Wu, Fengchang; Meng, Wei; Giesy, John P.; He, Zhongqi; Song, Lirong; Fan, Mingle |
| 论文摘要： |
Debris from aquatic macrophytes and algae are important recycling sources of phosphorus (P), which can result in continuing blooms of algae by recycling bioavailable P in the eutrophic lakes. However, knowledge of forms of P in aquatic macrophytes and algae and their contribution to internal loads of P in lakes is limited. Without such knowledge, it is difficult to develop appropriate strategies to remediate and or restore aquatic ecosystems that have become eutrophic. Therefore, in this work, P was extracted from six types of aquatic macrophytes and algae collected from Tai Lake of China and characterized by use of solution P-31-nuclear magnetic resonance (NMR) spectroscopy. When extracted by 0.5 M NaOH-25 mM EDTA, extraction recovery of total P(TP) and organic P(P-o) exceeded 90 %. Concentrations of P-o in algae and aquatic macrophytes were 5552 mg kg(-1) and 1005 mg kg(-1) and accounted for 56.0 and 47.2 % of TP, respectively. When P-o, including condensed P, was characterized by solution P-31-NMR P-o in algae included orthophosphate monoesters (79.8 %), pyrophosphate (18.2 %), and orthophosphate diester (2.0 %), and P-o in aquatic macrophytes included orthophosphate monoesters (90.3 %), pyrophosphate (4.2 %), and orthophosphate diester (5.5 %). Additionally, orthophosphate monoesters in algal debris mainly included beta-glycerophosphate (44.1 %), alpha-glycerophosphate (13.5 %), and glucose 6-phosphate (13.5 %). Orthophosphate monoesters in aquatic macrophytes mainly included beta-glycerophosphate (27.9 %), alpha-glycerophosphate (24.6 %), and adenosine 5' monophosphate (8.2 %). Results derived from this study will be useful in better understanding nutrient cycling, relevant eutrophication processes, and pollution control for freshwater lakes. |
