Seasonal changes, life cycle, and production of a psychrophilic chironomid (Propsilocerus akamusi) in a Chinese Lake

Seasonal changes, life cycle, and production of a psychrophilic Chironomidae species, Propsilacerus akamusi (Tokunage), were studied in eutrophic Lake Donghu. The P akamusi population was characterized by a single annual reproduction period during late November to December, and the larval growth mainly occurred in winter. Most of P akamusi were univoltine, while some of them came to emergence in two years or more. The average density and biomass were 318.9 ind./m(2) and 0.57 g dry weight /m(2) during January 1998 to June 2000, respectively, but these values did not include any summer measurement,; since the larvae aestivated in the deep sediment layer and could not be sampled routinely in summer. The annual production of P akamusi was 2.73g dry weight/m(2), and the corresponding production/biomass ratio was 4.60.

Seasonal changes, life cycle, and production of a psychrophilic Chironomidae species, Propsilacerus akamusi (Tokunage), were studied in eutrophic Lake Donghu. The P akamusi population was characterized by a single annual reproduction period during late November to December, and the larval growth mainly occurred in winter. Most of P akamusi were univoltine, while some of them came to emergence in two years or more. The average density and biomass were 318.9 ind./m(2) and 0.57 g dry weight /m(2) during January 1998 to June 2000, respectively, but these values did not include any summer measurement,; since the larvae aestivated in the deep sediment layer and could not be sampled routinely in summer. The annual production of P akamusi was 2.73g dry weight/m(2), and the corresponding production/biomass ratio was 4.60.

Chinese Academy of Sciences [KZCX2-YW-419]; National Natural Sciences Foundation of China [50730529, 30770404]