UVC-induced lysis and detritus production of Oscillatoria limnetica in a two-stage continuous-flow system

TY - JOUR

T1 - UVC-induced lysis and detritus production of Oscillatoria limnetica in a two-stage continuous-flow system

AU - Van Hannen, E.J.

AU - Gons, H.J.

N1 - Reporting year: 1997 Metis note: 2246; CL; AFW; file:///L:/Endnotedatabases/NIOOPUB/pdfs/Pdfs1997/VanHannen_ea_2246.pdf

PY - 1997

Y1 - 1997

N2 - In order to study in model systems the role of heterotrophic micro-organisms in the aquatic microbial food web, a natural food source consisting of senescent primary producer cells is indispensable. A two-stage continuous-flow system with the ability to produce detritus continuously is presented. In the first stage, a primary producer, i.e. the cyanobacterium Oscillatoria limnetica, was cultured. The second stage was fed with UVC-killed primary producer cells from the first stage. A control second stage received living primary producer cells. Both second stages were filled with prefiltered lake water in order to provide a natural inoculum of bacteria. During a 2 month experiment, the system was tested for its ability to produce detritus (first stage of detritus, i.e. lysis of the cell material). Chlorophyll a concentrations proved to be adequate for calculating specific lysis rates. Very high specific lysis rates were found after killing the cells with UVC as compared to the control stage. [KEYWORDS: Phytoplankton detritus; lake phytoplankton; oligotrophic lake; fresh-water; decomposition; bacteria; dynamics; algae]

AB - In order to study in model systems the role of heterotrophic micro-organisms in the aquatic microbial food web, a natural food source consisting of senescent primary producer cells is indispensable. A two-stage continuous-flow system with the ability to produce detritus continuously is presented. In the first stage, a primary producer, i.e. the cyanobacterium Oscillatoria limnetica, was cultured. The second stage was fed with UVC-killed primary producer cells from the first stage. A control second stage received living primary producer cells. Both second stages were filled with prefiltered lake water in order to provide a natural inoculum of bacteria. During a 2 month experiment, the system was tested for its ability to produce detritus (first stage of detritus, i.e. lysis of the cell material). Chlorophyll a concentrations proved to be adequate for calculating specific lysis rates. Very high specific lysis rates were found after killing the cells with UVC as compared to the control stage. [KEYWORDS: Phytoplankton detritus; lake phytoplankton; oligotrophic lake; fresh-water; decomposition; bacteria; dynamics; algae]

U2 - 10.1093/plankt/19.6.723

DO - 10.1093/plankt/19.6.723

M3 - Article

SN - 0142-7873

VL - 19

SP - 723

EP - 733

JO - Journal of Plankton Research

JF - Journal of Plankton Research

IS - 6

ER -