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SCI论文目录 |
Effect of available food and temperature on the growth and
reproduction of Daphnia rosea
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出 版 社:Journal of Freshwater Ecology [J. Freshwat. Ecol.]. |
发表时间:2000 |
台 站:
东湖湖泊生态系统试验站
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作 者:Xie, Ping; Iwakuma, T; Fujii, K |
点 击 率:2742 |
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关 键 字:null |
摘 要:null |
关 键 字(英文):null |
摘 要(英文):Population parameters of Daphnia rosea were studied at various
concentrations of Chlorella sp. (0.25, 0.75 and 3.0 mg C L
super(-1)) at several temperatures (20, 25, 28, and 30 degree C)
in the laboratory. Although there were some differences in the
degrees of the effects of the various temperature-food
combinations, both food and temperature exerted influences on
almost all of the main population parameters of D. rosea. At a
water temperature of 28 degree C, growth and reproduction were
reduced, and at the lowest food level (0.25 mgC L super(-1)),
reproduction failed. D. rosea did not survive at 30 degree C in
spite of abundant food supply, indicating that 30 degree C is a
physiological limit. A positive relationship between body length
and brood size was recognized at high and medium food levels. The
slope of the regression was the highest at the highest food level
and at the lowest temperature (20 degree C). The low food level
exerted a negative influence on the net reproductive rate by
lowering the size of egg-bearing females, by decreasing the brood
size of each size class, by decreasing the brood number per
female, and by increasing the period of empty brood chamber. High
water temperature (28 degree C) also exerted a negative influence
on the net reproductive rate in a similar way. For the better
understanding of the key factors driving the midsummer dynamics of
daphnids in the field, it may be of crucial importance to compare
the population parameters of the field populations with
experimentally derived values under controlled conditions of food
concentration and temperature.
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