Short‐term displacement of Planktothrix rubescens (cyanobacteria) in a pre‐alpine lake observed using an autonomous sampling platform

摘要: Short-term changes in temporal and spatial distributions of the toxic cyanobacterium Planktothrix rubescens Lake Zurich were investigated using high-resolution data sets acquired with an autonomous surface vessel (ASV). Data profiles recorded a multi-parameter probe while ASV navigated along 1.5 km toward waypoint located on other side lake by global positioning system. We deployed seven times five consecutive days during stratification period (July 2011) to generate cross-sectional views temperature, light, oxygen, phycoerythrin chlorophyll fluorescence from 18 m. The also used compute daily photosynthetic rates. showed reshaping P. distribution metalimnion both horizontal vertical axes, patches shore-to-shore spreading. A thermocline depression observed after 16 h sustained winds forced accumulation downwind shore. compression its downward shift 6 m within 24 suggested modulation longitudinal seiche following wind event. This passive transport metalimnetic population resulted 90% light reduction, decrease averaged rate +21 mmol O2 m−2 d−1 −10 d−1. Negative rates computed 2 d out 5 d, meaning that seiches significantly affected balance between oxygen production utilization Zurich, especially because it is dominant primary producer.