【摘要】 本文报道了南京玄武湖微型裸腹溞和短尾秀体溞的种群变动和生产量的研究结果,并分析了影响它们的生态因子。计算了种群的瞬时出生率(b),瞬时增长率(r)和瞬时死亡率(d)。观察了微型裸腹溞怀卵量的季节变化。微型裸腹溞生长季节平均生物量为87.51μg/L(干重),生产量为8292.36μg/L(干重),P/B系数为94.76;短尾秀体溞生长季节平均生物量为9.58μg/L(干重),生产量为480.02μg/L(干重),P/B系数为50.52。更多还原

【Abstract】 This paper reports the results of estimations of population dynamics and production of Moina micrura and Diaphanosoma brachyurum in Xuanwu Lake in Nanjing. The ecological factors affecting the population dynamics and production of these two species are analyzed. The instantaneous birth rate(b), the instantaneous growth rate(r) and the instantaneous death rate(d) of the cladocera were calculated. Seasonal variations in egg density, mean broodsize and proportion of gravid adults were recorded. The mean growing-season biomass was 87.51 μg dry weight/l for Moina micrura and 9.58 μg dry weight/l for Diaphanosoma brachyurum. The average growing-season production was 8 292.36 μg dry weight/l for Moina micrura and 480.02 μg dry weight/l for Diaphanosoma brachyurum. The average growing-season P/B ratio was 94.76 for Moina micrura and 50.52 for Diaphanosoma brachyurum.更多还原