Abundance and production ofBranchiura sowerbyi(Oligochaeta: Tubificidae) in two typical shallow lakes (Hubei, China)

An April 1996 to March 1997 comparative study on the abundance and secondary production ofBranchiura sowerbyiBeddard, 1892 in two typical shallow lakes showed that in Houhu, an algae-dominated lake, the worm density (68 ind·m−2) peaked in July, biomass (1.930 g·m−2) peaked in June, while in Biandantang, a macrophyte-dominated lake, standing stock (density: 60 ind·m−2; biomass: 1.019 g·m−2in wet weight) peaked in December. Secondary production of the animal in Houhu Lake was 3.413 g wet wt m−2a−1, a little more than that (2.675 g wet wt m−2a−1) in Biandantang Lake. Their turnover rates (P/B ratios) were 4.0 and 5.0, respectively.