| Centropages tenuiremis is a mainly dominant species in Xiamen waters during winter-spring. There is a noticeable character in its life history, that in May and June, when the population of this species begin to reduce gradually, the females could produce diapause eggs with long spines on their surface to over summer-autumn (from July to November). The seasonal and diel variation in fecundity of females in situ. were observed, and the pattern of spawning and its ecological significance were also discussed. The differences of biochemistry component, respiration, isoenzyme, and total proteins electrophoresis between diapause and subitaneous eggs were preliminarily investigated as well. The main results are as follows:1. The effect of environmental conditions in Xiamen waters on the diapause emerging in eggs Both the temperature and photoperiod {in situ.) have a obvious effect on the diapause emerging in eggs, respectively. With the temperature of sea area in situ, and the photoperiod during collecting samples, the two most important factors in inducing diapause, as the independent variable, whether the egg was in diapause (or whether the female laid diapause eggs) was regarded as the dependent variable, and the probabilistic equations of egg in diapause and female laying diapause eggs were established. Egg in diapause or not: Logit (P) =- 41.832+1.422x1(sea-water temperature)+0.509x2(photoperiod); female laying diapause eggs or not: Logit (P) = -89.001+6.611x(photoperiod) The former reflected the effect of environmental conditions on the amount of diapause eggs of this species in Xiamen waters, and it is important to study the population dynamics of this species in this area; while the latter reflected the effect of environmental conditions on inducing the female of this species to lay diapause eggs, and it is important to research the diapause inducers of this species in this area and the physiological mechanism of diapause.2. The seasonal variation in diel egg production In winter-spring with lower temperature of seawater the copepods tended to lay in night, while in summer with higher temperature of seawater they tended to lay in daytime. That is, it showed the seasonal variation in diel egg production of model. Such a model of egg production would be benefit this species to survive in this waters area and become a dominant species. For subitaneous eggs, in winter-spring with long hatching time, the females lay in nighttime in upper water layer. The distance for eggs sinking to the sea-bottom is also long. This pattern would allow the eggs enough time to hatch before sinking to sea-bottom. In summer with obviously short hatching time, the females lay in daytime in deeper water layer. The eggs could also hatch before sinking to sea-bottom .For diapause eggs, it is laid in daytime in deeper water layer and may quickly sink to the sea-bottom. Thus, it would shorten the time of staying in water column, and prevent from being ingested before sinking to the sea-bottom.3. The seasonal variation in egg production rate in situ. After the population of C. tenuiremis occurred in the Xiamen waters (at the beginning of winter), the average rate of subitaneous egg production was higher at first and then declined. After fluctuating several times, it fell to the lowest value (at the beginning of summer), and then the population of this species disappeared from this area. The seasonal variation in egg production model of C. tenuiremis is that the subitaneous egg production might be increased in the favorable environment during winter-spring; and it might be reduced, and the females began to produce diapause eggs when the ambient environment became unfavorable to survival. Such a model will ensure the existence of this species in this area.4. The comparison of the biochemical contents between subitaneous and diapause eggs The dry weight and the contents of each biochemical components in a diapause egg were all more than the ones in a subitaneous egg; the comparatively content of lipid in t...
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