Abstract: This paper deals with the characteristics of reproductive distribution of hymenopterous parasitoid population on the basis of 23 sets of fecundity data for 10 species of it. The result show that all of these species have a similar distribution of reproduction with time，which is concentrated in the first d days，and in first d/2 days in particular. The contribulion of population reproduction to population growth in a reproductive period of d almost reaches to 100%，of which，most contribution is achieved in reproductive period of d/2. This characteristics of reproductive distribution is of importance to determining the intrinsic increase rate of parasitoid population and understanding its quantitative dynamics with time.

Key words: Hymenopterous parasitoid, Fecundity, Reproductive distribution, Population dynamics, sulfate-reducing prokaryote, ASP flooding, produced water, high-throughput sequencing, microbial community structure, hydrogen sulfide., petroleum reservoir