Effective aerial monitoring of cyanobacterial harmful algal blooms is dependent on understanding cellular migration

Publication date: July 2019Source: Harmful Algae, Volume 87Author(s): Mingzhi Qu, Stephen Anderson, Pin Lyu, Yasir Malang, Jizhou Lai, Jianye Liu, Bin Jiang, Feng Xie, Hugh H.T. Liu, Daniel D. Lefebvre, Yuxiang S. WangAbstractCyanobacterial harmful algal blooms (CHABs) degrade water quality and may produce toxins. The distribution of CHABs can change rapidly due to variations in population dynamics and environmental conditions. Biological and ecological aspects of CHABs were studied in order to better understand CHABs dynamics. Field experiments were conducted near Hartington, Ontario, Canada in ponds dominated by Microcystis aeruginosa and CHABs floating experiments were conducted at Lake Taihu during the summers of 2015 and 2016. Single colonies composed of hundreds to thousands of cells with an average median of 0.2–0.5 mm in diameter were the basic form assumed by the Microcystis, and this remained the same throughout the growing season. Thorough mixing of the water column followed by calm conditions resulted in over 90% of the cyanobacteria floating after 1 h. Multiple colonies floated on the water surface in four types of assemblages: aggregates, ribbons, patches, and mats. It is the mats that are conventionally considered the blooming stage of cyanobacteria.Presence of CHABs on open water surfaces also depends on environmental influences such as direct and indirect wind effects. For example, field tests revealed that the surface coverage of CHABs can be reduced t...
Source: Harmful Algae - Category: Environmental Health Source Type: research