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21.
武汉后湖湖球蚬的周年生产量 总被引：2，自引：0，他引：2
采用体长频率法和瞬时生长率法对后湖湖球蚬Sphaerium lacustre的周年生产量进行了测算. 结果表明两种方法得到的生产量较为吻合.生产量的带壳湿重和去壳干重分别是体长频率法1.048 g/(m2a) 0.0599 g/(m2a); 瞬时生长率法1.178 g/(m2a), 0.0673 g/(m2a).对应的P/B系数为3.23.4. 相似文献
22.
From June 2003 to June 2004, an investigation on the life cycle, production and trophic basis of dominant species of macrozoobenthos community in a second-order river of the Hanjiang River basin, Hubei, China was carded out. The results showed that the dominant species Leptophlebia sp. and Ephemera sp. appeared to develop two generations per year, and there was a small overlap in the two generations of both species. The pupation of Leptophlebia sp. mainly occurred in autumn and winter, while pupation of Ephemera sp. mainly took place in summer and winter. The standing stocks of the Leptophlebia sp. population and Ephemera sp. population had two peaks in a year. The cohort production and cohort P/B ratio of the Leptophlebia sp. population estimated by size frequency method were 19.018 1 g/m^2.a and 5.7 respectively, while its annual production and P/B ratio were 38.036 2 g/m^2.a and 11.4. The cohort production and cohort P/B ratio of the Ephemera sp. population were 38.015 9 g/m^2.a and 5.9, while its annual production and P/B ratio were 76.031 8 g/m^2.a and 11.8. 相似文献