title: Role of gas vesicles and intra-colony spaces during the process of algal bloom formation.
abstract: Aggregation morphology, vertical distribution, and algal density were analyzed during the algal cell floating process in three environments. The role of gas vesicles and intra-colony spaces was distinguished by algal blooms treated with ultrasonic waves and high pressure. Results demonstrated that the two buoyancy providers jointly provide buoyancy for floating algal cells. The results were also confirmed by force analysis. In the simulation experiment, the buoyancy acting on algal cells was greater than its gravity at sample ports 2 and 3 of a columnar-cultivated cell vessel, and intra-colony spaces were not detected. In Taihu Lake, gas vesicle buoyancy was notably less than total algal cell gravity. Buoyancy provided by intra-colony spaces exceeded total algal cell gravity at the water surface, but not at other water depths. In the Daning River, total buoyancies provided by the two buoyancy providers were less than total algal cell gravity at different water depths.
authors.affiliation: State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environment Sciences, 8 Dayangfang BeiYuan Road, Chaoyang District, Beijing 100012, China. yszhang@craes.org.cn
authors.forename: Yongsheng
authors.initials: Y
authors.lastname: Zhang
authors.forename: Binghui
authors.initials: B
authors.lastname: Zheng
authors.forename: Xia
authors.initials: X
authors.lastname: Jiang
authors.forename: Hao
authors.initials: H
authors.lastname: Zheng
mesh_terms: D000458:Cyanobacteria / Q000254:growth & development*; D005068:Eutrophication; D005740:Gases
chemical_list: D005740:Gases