
TY  - JOUR
A1  - Mitchell, BD 
A1  - Williams, WD 
T1  - Population dynamics and production of <I>Daphnia carinata</I> (King) and <I>Simocephalus exspinosus</I> (Koch) in waste stabilization ponds
JF  - Marine and Freshwater Research
JO  - Mar. Freshwater Res.
Y1  - 1982
VL  - 33
IS  - 5
SP  - 837
EP  - 864
KW  - 
UR  - https://doi.org/10.1071/MF9820837 
N2  - The population dynamics and production of D. carinata and S. exspinosus were investigated in two adjacent maturation-type waste stabilization ponds in South Australia. Population parameters (b', r', and d') for both species were determined from population density, brood size, and egg-development time. Length-weight relationships were determined for both species. Growth of D. carinata was investigated experimentally. Net production of both species was determined using Edmondson's population turnover- time model. Production of D. carinata was also determined using Winberg's biomass turnover model. D. carinata, the numerically dominant species, was a cold water form; high water temperatures increased mortality and reduced growth rate. Both species were food-limited at high population densities. Total annual net production of D. carinata in pond 1 during 1977 (345 g dry wt m-2): calculated using the population turnover-time model, was the highest yet recorded for any planktonic cladoceran. Annual net production of D. carinata determined using the population turnover-time model exceeded annual production determined using the biomass turnover model by 100%. Overestimation of daily production rate was highest during periods of high egg mortality. Total annual net production of D. carinata and S. exspinosus (biomass turnover model) represented a nutrient store equivalent to less than 6% of total PO4-P and total nitrogen retained in the ponds annually. 
ER  -

