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951.
952.
台湾海峡南部夏季微型浮游动物对浮游植物的摄食压力及其生产力 总被引:6,自引:0,他引:6
2004年7~8月在台湾海峡南部的5个站位,用稀释法研究了浮游植物的生长率,微型浮游动物对浮游植物的摄食率及其生产力.微型浮游动物主要为无壳纤毛虫,尤其是急游虫类和侠盗虫类.浮游植物的生长率为0.52~0.72/d,浮游动物的摄食率为0.45~1.33/d,相当于每天摄食浮游植物现存量的36%~74%和初级生产力的88%~141%.微型浮游动物的次级生产力(MP02)为初级生产力的28.5%~58.4%.表明微型浮游动物在台湾海峡夏季海洋生态系统的能量流动中发挥着重要的作用. 相似文献
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954.
Abstract. The production rates of intertidal algae at seven study sites in the Saklanha Bay area. South Africa, were measured monthly for 15 months. Algae grew rapidly and formed extensive, permanent mats on shores that were enriched with nutrients from the dissolved guano of seabirds. The most significant correlate of limpet (Patella granulans) growth was the rate of algal production; more rapid limpet growth on nutrient-rich shores, combined with the effects of predation by African Black Oystercatchers Haematopus moquini on limpets, led to differences in the size structures and life-history patterns of populations of limpets on enriched and unenricheci shores. The rate of primary production affected relationships between intertidal organisms at all trophic levels and influenced patterns of organization within the community. 相似文献
955.
Liu Xiaolin Chang Yaqing Xiang Jianhai Li Fuhu Liu Xianjie Brovkina Elena Pavlovna 《海洋学报(英文版)》2003,22(2):255-263
Abstract-Based on the research of juvenile (2, 3, 4 months) growth and survival of three popu-lations of two different geographic areas in Chlamys farreri from Russian and China and their F_1 hybridsderived from Chinese cultural population (CC)×Russian population (RW), Chinese wild popu-lation (CW)×Russian population (RW), Russian population (RW)×Chinese wild popula-tion (CW), the study of the medium-term (6, 8, 10, 12 months) growth and development ofChlamys farreri was carried out. The four determined results indicated that there existed different ex-tent heterosis (3%~52%) for the growth in three types of F_1 hybrids, and the offspring derived fromCC×R had a stronger heterosis among the crosses at the medium-term; the uptrend among traitsare wet weight>shell width>shell length>shell height, Chinese cultural population could be recog-nized as excellent parent, and seasonal variations influence very much on the daily increment and growthrate of each trait of Chlamys farreri and it is only able to 相似文献
956.
Lee A. Fuiman 《Journal of Sea Research》1997,37(3-4)
Eye migration, asymmetrical pigmentation, and a 90° rotation in posture are developmental changes that unify all flatfishes and facilitate a transition from a pelagic to a benthic existence. Settlement places the fish in new environmental conditions which may require different types and levels of performance for survival compared to those needed in the water column. Since structure and performance vary as a consequence of ontogeny, it is likely that natural selection has acted on the ontogeny of flatfishes differently from fishes that do not settle (pelagic fishes) to provide different survival skills by the time flatfishes settle. This paper provides examples of quantitative methods for comparing fish ontogenies in the context of three predictions: (1) different flatfish species undergo settlement at a common ontogenetic state; (2) they have a common set of skills at settlement that differ from those of pelagic species of the same ontogenetic state; and (3) skills or features that appear earlier in the ontogenetic program of flatfishes than in pelagic fishes suggest attributes that are important to survival in a benthic habitat. Preliminary comparisons suggest that flatfishes may have accelerated development of their mechanosensory system relative to pelagic species. Firm conclusions about ecologically important differences between the pelagic and benthic habitats derived from analyses of ontogenetic events will require more kinds of data from a broader selection of species. 相似文献
957.
于1990年6月在哈尔滨市东北林业大学实验林场一水池中采到微齿喜马拉雅低额溞,根据实验结果应用生物统计学方法对它的生长和种群增长进行研究。结果表明,在不同温度条件下性成熟时间与水温的关系为,雌性(10-30°C):h=8072t-1.313(r=0.985, P<0.01);雄性(5-25°C):h=1074t-0.855(r=0.9844,P<0.01)。在20±1°C条件下,其体长增长模型为:lt=3.334-2.7345e-0.1117t。龄期(x)与年龄(t,d)的关系为:雌体:t=0.07169x2+1.3808x-1.7361;雄体:t=0.8425x2+2.534x-1.8600。内禀增长率(rm)为0.4076。种群增长呈“logistic”型,其方程式为:y=3625/[1+e(3.848-0.164t)]。 相似文献
958.
959.
960.
硫酸铵对钝顶螺旋藻(spirulina platensis)生长的影响 总被引:2,自引:0,他引:2
本实验利用硫酸铵代替zarrouk培养基中的硝酸钠。在硫酸铵的最适用量范围内钝顶螺旋藻spirulina platensis生长良好。不同用量的硫酸铵,对钝顶螺旋藻的生长,以及叶绿素和脱镁叶绿素含量有明显影响。钝顶螺旋藻生长,最佳时硫酸铵用量为0.1g/l,粗蛋白含量为51.35%。 相似文献