Abstract: The 48 h LC₅₀ of DDT to Moina macrocopa was determined by acute toxicity test, and the effects of different concentrations (1, 8, 16, 24, 32 and 40 μg·L^-1) of DDT on the life table demography of M. macrocopa was studied by life table demography. The results showed that the 48 h LC₅₀ of DDT to M. macrocopa was 324 μg·L^-1. 1-40 μg·L^-1 of DDT had no significant effects on the life expectancy at birth, generation time, net reproductive rate, and gross productive rate of M. macrocopa (P>0.05), but significantly affected the intrinsic rate of population increase (r_m) (P<0.05). The r_m of M. macrocopa increased markedly at 8, 16 and 40 μg·L^-1 of DDT, compared with the blank control, indicating that when the life table demography of M. macrocopa was used to monitor the ecological effects of sublethal concentrations of DDT, r_m could be a sensitive indicator.

Key words: Koelreuteria paniculata, seed germination, polyethylene glycol, exogenous Ca²⁺, drought stress.