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毕克卷转虫Ammonia beccarii(Linnaeus,1758)是潮间带和陆架浅海沉积物中常见的底栖有孔虫类群,但因活体培养困难,国际间对其基础生物学研究甚少。本工作成功对A.beccarii建立了室内培养,采用食物移除法测定其对硅藻的摄食率,探讨了温度和食物浓度对其房室生长和摄食率的影响。实验显示A.beccarii成体每次繁殖可产生约50—100个子代幼体,2个月左右完成2个壳圈(约15个房室)的生长,达到成体的3—4个壳圈(20个房室以上)约需3—5个月。此外,A.beccarii的房室生长受不同培养温度的影响,20°C下房室长径和短径的增长皆快于15°C:15°C长、短径的平均增长率分别为0.99、0.93μm d-1;20°C壳体长、短径的平均增长率分别为2.21、2.10μm d-1,温度较低时壳体生长呈常见的椭圆形体态,温度升高壳体较大且胖圆。在温度为12、15、18、21、24°C和硅藻浓度200—1 000cells mm-2的培养条件下,A.beccarii的摄食率对硅藻浓度的响应模型各参数均有统计显著性,最大摄食率(Imax)和半饱和食物浓度(k)均随温度的升高而降低。随着温度的升高,Imax由12°C的1 014.23diatoms ind.-1 h-1降低到24°C时的656.26diatoms ind.-1 h-1,k由195.77diatoms mm-2降低到92.65diatoms mm-2,摄食率(I)的变化范围约为50—1 000diatom ind.-1 h-1。推测12—15°C可能为A.beccarii的最适温度范围,此温度也与野外调查黄、东海陆架表层沉积物中A.beccarii的丰度分布高值时的环境温度区间相符。本研究结果显示A.beccarii在海洋底栖生态系统中对摄食藻类具有一定的生态学功能,并具有喜好低温的特性。
Ammonia beccarii (Linnaeus, 1758) is a common benthic foraminifer group in intertidal and shallow marine sediments. However, due to the difficulties in living culture, little is known about its basic biology. In this work, A.beccarii was successfully established in laboratory and its feeding rate to diatoms was determined by food removal method. Effects of temperature and food concentration on atrioventricular growth and feeding rate were also discussed. Experiments have shown that A. bertarii adults can produce about 50-100 larvae per replicate and about 2 larvae (about 15 atriovenuses) within about 2 months reaching an adult population of 3-4 shells (20 Room above) takes about 3-5 months. In addition, A.beccarii’s atrioventricular growth was influenced by the temperature of culture, and the increase of both the major axis and the minor axis at 20 ° C was faster than at 15 ° C: 15 ° C and the average minor axis was 0.99 , 0.93μm d-1. The average growth rates of the long and short diameters of the shell at 20 ° C were 2.21 and 2.10μm d-1 respectively. When the temperature was low, the growth of the shell was a common oval body. Big and fat round. Under the culture conditions of 12, 15, 18, 21, 24 ° C and diatom concentration of 200-1 000 cells mm-2, the parameters of A.beccarii’s response rate to diatom concentration were all statistically significant , Maximum food intake rate (Imax) and semi-saturated food concentration (k) decreased with increasing temperature. With increasing temperature, Imax decreased from 1 014.23diatoms ind.-1 h-1 at 12 ° C to 656.26diatoms ind.-1 h-1 at 24 ° C, with k decreasing from 195.77diatoms mm-2 to 92.65 diatoms mm-2, the ingestion rate (I) varied from about 50-1 000 diatom ind.-1 h-1. It is speculated that 12-15 ° C may be the optimum temperature range for A.beccarii, which is also consistent with the field temperature range at the high value of A.beccarii abundance distribution in the surface sediments of the Yellow Sea and East China Sea. The results show that A. beccarii in the marine benthic ecosystems for the algae has some ecological functions, and has the preference for low temperature characteristics.