Effects of acute gamma-irradiation on the aquatic microbial microcosm in comparison with chemicals.
Effects of acute gamma-irradiation were investigated in the aquatic microcosm consisting of green algae (Chlorella sp. and Scenedesmus sp.) and a blue-green alga (Tolypothrix sp.) as producers; an oligochaete (Aeolosoma hemprichi), rotifers (Lecane sp. and Philodina sp.) and a ciliate protozoan (Cyclidium glaucoma) as consumers; and more than four species of bacteria as decomposers. At 100 Gy, populations were not affected in any taxa. At 500-5000 Gy, one or three taxa died out and populations of two or three taxa decreased over time, while that of Tolypothrix sp. increased. This Tolypothrix sp. increase was likely an indirect effect due to interspecies interactions. The principal response curve analysis revealed that the main trend of the effects was a dose-dependent population decrease. For a better understanding of radiation risks in aquatic microbial communities, effect doses of gamma-rays compared with copper, herbicides and detergents were evaluated using the radiochemoecological conceptual model and the effect index for microcosm.
Fuma
Shoichi
S
Environmental Radiation Effects Research Group, National Institute of Radiological Sciences, Chiba 263-8555, Japan. fuma@nirs.go.jp
Ishii
Nobuyoshi
N
Takeda
Hiroshi
H
Miyamoto
Kiriko
K
Yanagisawa
Kei
K
Doi
Kazutaka
K
Kawaguchi
Isao
I
Tanaka
Nobuyuki
N
Inamori
Yuhei
Y
Polikarpov
Gennady G
GG
D000818:Animals; D017753:Ecosystem; D056890:Eukaryota / Q000528:radiation effects*; D020387:Food Chain; D005720:Gamma Rays; D006863:Hydrogen-Ion Concentration; D019216:Metals, Heavy / Q000009:adverse effects*; D009835:Oligochaeta / Q000528:radiation effects*; D016802:Oligohymenophorea / Q000528:radiation effects*; D011839:Radiation, Ionizing; D012403:Rotifera / Q000528:radiation effects*; D018675:Toxicity Tests; D014871:Water Microbiology; D014873:Water Pollutants / Q000009:adverse effects*; D014881:Water Supply
D019216:Metals, Heavy; D014873:Water Pollutants