Authors: Yanqing Ding Boqiang Qin Hai Xu Xiaodong Wang
Publish Date: 2016/05/06
Volume: 23, Issue: 16, Pages: 16183-16193
Abstract
Sediments play important roles as nutrient reservoir especially in shallow lake ecosystem The water column of large shallow lakes is often stable but also disturbed by turbulence causing resuspension of sediments While considerable research has been carried out to investigate the influence of sediment resuspension on nutrient release fewer studies have been done to understand the contribution of alkaline phosphatase activity APA in water as a response to the two conditions turbulence and stability Also effects of the two lake conditions on photosynthetic efficiency of phytoplankton are still poorly understood This study will evaluate the effect of these two conditions on photosynthetic efficiency and APA Sediments used in the indoor experiments were collected from Zhushan Bay in Lake Taihu Turbulence was generated by rotors to simulate the strong windinduced disturbance in Lake Taihu Results of the experiments showed that TN and TP in the stable and episodically turbulent conditions were not significantly different with TN ranging from 134 to 190 mg/L and TP from 008 to 018 mg/L Whereas the soluble reactive phosphorus in the episodically turbulent condition was significantly higher than in the stable condition Episodic turbulence could enhance P cycling by resuspending sedimentassociated P which alleviated algal P limitation In stable conditions P deficiency induced the production of high APA which enhanced the availability of P Although episodic turbulence could also cause increased algal biomass photosynthetic efficiency of the algae was also affected not only by the nutrients but also by many other factors especially light availability Our results suggest that episodic turbulence is an important driver of biogeochemical cycling in large shallow hypertrophic lake ecosystemWe are grateful to the Lake Taihu Laboratory for Lake Ecosystem Research TLLER which provided the experiment platform Jingchen Xue and KeXu Chi assisted with laboratory analyses This work was funded through the National Natural Science Foundation of China Grant No 41501518 and the Natural Science Foundation of Jiangsu Province BK20140184 And it also was supported by the Fundamental Research Funds for the Central Universities 2014QNA86 and A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions We also thank the anonymous reviewers for their constructive comments and helpful suggestions
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