Development of the “plankton emergence trap/chamber (PET Chamber)”, a new sampling device to collect in situ germinating cells from cysts of microalgae in surface sediments of coastal waters

Diversity and germination patterns of diatom resting stages at a coastal Mediterranean site

“…We are not aware of studies assessing in situ germination rates of diatom resting stages in the marine environment. Germination chambers deployed in the sediments (Ishikawa et al 2007) might represent promising tools to investigate the dynamics of germination, assuming that careful manipulation of sediment samples is used to avoid exposure to light. Quantitative assessment of the recruitment rates in unicellular organisms is tricky because germinated cells only represent a minute fraction of the population in the water column (Ishikawa et al 2007), and the concomitant vegetative growth masks the link between inoculum size and population development.…”

“…Germination chambers deployed in the sediments (Ishikawa et al 2007) might represent promising tools to investigate the dynamics of germination, assuming that careful manipulation of sediment samples is used to avoid exposure to light. Quantitative assessment of the recruitment rates in unicellular organisms is tricky because germinated cells only represent a minute fraction of the population in the water column (Ishikawa et al 2007), and the concomitant vegetative growth masks the link between inoculum size and population development. In lakes, recruitment from the sediment and sinking to the sediment are higher under mixed con ditions, while seasonal stratification of the water column acts as a 'cap' limiting both positive and negative migrations (Hansson 1995(Hansson , 1996.…”

Alexandrium catenella cyst dynamics in a coastal embayment : temperature dependence of dormancy, germination, and bloom Initiation

“…The most sophisticated are the plankton emergence trap (PET) chambers designed by Ishikawa et al (2007), which were deployed on the seafloor of Ago Bay, Japan to measure the emergence flux of A. catenella (2014). Each PET chamber consists of a base cylinder plugged with natural sediment and a top cylinder covered by a 10 µm mesh to keep the plankton inside but allow water exchange with the in situ environment.…”

“…The emergence flux of A. catenella from natural sediments was measured using plankton emergence trap (PET) chambers (Ishikawa et al 2007) (Fig. 4c).…”

“…Cores were directly collected in the lower portion of the PET chamber, and the core was carefully pushed to the top of the core tube. The upper chamber of the PET was then affixed to the lower chamber as described by Ishikawa (2007).…”