研究了不同起始细胞密度与硅酸盐浓度对海洋卡盾藻(Cm)与中肋骨条藻(Sc)及锥状斯氏藻(St)之间种间竞争的影响,利用竞争抑制参数对相互间的竞争关系进行了分析,并引入体积竞争抑制系数的概念。结果表明:海洋卡盾藻的环境容量不受起始细胞密度(100—3600cells/mL)的影响,但随着起始接种密度的增加,达到最大细胞密度和进入稳定生长期的时间均提前。在硅缺乏的条件下,中肋骨条藻仍能保持一定生长,并能在与海洋卡盾藻之间的种间竞争中保持数量优势,但硅酸盐浓度的增加有利于其种间竞争。初始细胞密度和接种比例对3种赤潮藻类之间的种间竞争影响明显,总体来说海洋卡盾藻在竞争中处于劣势。当海洋卡盾藻细胞密度远远高于中肋骨条藻时(Cm:Sc=6:1),海洋卡盾藻才能在与中肋骨条藻的竞争中取胜;而在与海洋卡盾藻共培养条件下,锥状斯氏藻具有一定竞争优势,其对海洋卡盾藻的体积抑制系数(α')是后者(β')的27—100倍。但在所有处理中均没有绝对优胜者,竞争结果都会出现不稳定的平衡状态。
In order to understand the interspecies competition of Chattonella marina with other harmful algal bloom species, and to provide useful information for the control of C. marina bloom, the growth of C. marina and competition between C. marina (Cm) and two other harmful algal bloom (HAB) species, Skeletonema costatum (Sc) and Scrippsiella trochoidea (St), were studied, Experiments were conducted at three initial inoculation proportions according to their cell volumes, and four Si concentrations. The competition parameters were used to compare interspecific competition between the three algae, and the concept of volume competition parameter was firstly introduced. The carrying capacity (K) of C. marina showed no obvious changes in five different initial cell densities ranged from 100 cells/mL to 3600 cells/mL, however, the maximum cell density and the stable stage postponed with the decreasing of initial cell density. S. costatum had the ability to keep steady growth even in Si free culture, and held the predominance of cell number in the competition of C. marina. Meanwhile, the increase of Si level benefited the competition of S. costatum to C. marina. The initial cell density and inoculation proportion exhibited significant effects on interspecific competition of the three species. Although S. costatum grew faster than C. marina in the same initial cell density (600 cells/mL), the volume competition parameters between them (α' and β') were comparable. S. costatum won in the culture when its inoculation cell number overpassed that of C. marina (Cm:Sc=1:6, the same cell volume). C. marina predominated in the culture only when its cell number greatly preponderated over S. costatum (Cm:Sc=6:1). S. trochoidea produced strong inhibition effects on the growth of C. marina under all treatments of the experiment (Cm:St=1:1, 1:3, 3:1), and its volume compe-tition parameters to C. marina (α') were 27—100 times higher than the opposition (β'). Howev