Effect of suspended clay on growth rates of the cyanobacterium Cylindrospermopsis raciborskii

TY - JOUR

T1 - Effect of suspended clay on growth rates of the cyanobacterium Cylindrospermopsis raciborskii

AU - Brasil, Jandeson

AU - Huszar, Vera L.M.

AU - Attayde, José L.

AU - Marinho, Marcelo Manzi

AU - van Oosterhout, Frank

AU - Lürling, Miquel

N1 - 6475, AqE; Data archiving: property of and archived at WUR

PY - 2017

Y1 - 2017

N2 - Recent studies have shown that sediment resuspension may lead to the collapse of C. raciborskii dominance, which suggests that clay might have a negative effect on the growth of C. raciborskii. To test the hypothesis that suspended clay creates an unfavorable environment for growth of C. raciborskii, we exposed four different strains of this species to various concentrations of the clays kaolinite and bentonite, and monitored the biomass of each strain over the course of 1-week microcosm experiments. Contrary to our hypothesis, C. raciborskii was able to grow in suspensions of both clays. While kaolinite clay caused higher turbidity than bentonite, the growth rates of all four C. raciborskii strains were higher in kaolinite than in bentonite suspensions. C. raciborskii could still grow in clay concentrations that cause turbidity far above the levels found in natural lakes. Our study suggests that the reported collapse of C. raciborskii blooms with high concentrations of suspended sediments in tropical shallow lakes is probably not caused by the effects of suspended clay on light attenuation, but rather is a consequence of cell sinking or, possibly a response to disturbance events responsible for sediment suspension.

AB - Recent studies have shown that sediment resuspension may lead to the collapse of C. raciborskii dominance, which suggests that clay might have a negative effect on the growth of C. raciborskii. To test the hypothesis that suspended clay creates an unfavorable environment for growth of C. raciborskii, we exposed four different strains of this species to various concentrations of the clays kaolinite and bentonite, and monitored the biomass of each strain over the course of 1-week microcosm experiments. Contrary to our hypothesis, C. raciborskii was able to grow in suspensions of both clays. While kaolinite clay caused higher turbidity than bentonite, the growth rates of all four C. raciborskii strains were higher in kaolinite than in bentonite suspensions. C. raciborskii could still grow in clay concentrations that cause turbidity far above the levels found in natural lakes. Our study suggests that the reported collapse of C. raciborskii blooms with high concentrations of suspended sediments in tropical shallow lakes is probably not caused by the effects of suspended clay on light attenuation, but rather is a consequence of cell sinking or, possibly a response to disturbance events responsible for sediment suspension.

KW - LIGHT AVAILABILITY

KW - SUSPENDED SOLIDS

KW - CYANOBACTERIA

KW - INORGANIC TURBIDITY

KW - SEDIMENTATION

KW - international

U2 - 10.1127/fal/2017/1096

DO - 10.1127/fal/2017/1096

M3 - Article

SN - 1863-9135

VL - 191

SP - 13

EP - 23

JO - Fundamental and Applied Limnology

JF - Fundamental and Applied Limnology

IS - 1

ER -