Biological and chemical characteristics of the aged microcosm and its ecological significance.

衰老微观世界的生物化学特征及其生态意义。

• 批准号: 62480004
• 负责人: KURIHARA Yasushi
• 金额: $ 2.56万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1987
• 资助国家: 日本
• 起止时间: 1987 至 1988
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-62480004/
• 关键词: Microcosm; Closed system; Community metabolism activity; Bacteria; Serial transfer; 形質変化; 種間競争; 低濃度培地; 過老令化; 開放系; 閉鎖系; 群集維持; 構成種の単離

We have made observation on closed microcosms (medium:air = 2:1), which did not exchange gas with the atmosphere, when flasks were stoppered with rubber plugs at 25 d of cultivation. The population densities and the diural changes of dissolved oxygen in the closed microcosms were same as those in the control microcosm, which exchanged gas with atmosphere. The concentration of gaseous oxygen were almost constant in the closed microcosms. Thus, the population densities and the level of community metabolism activity could be maintained after microcosms were totally closed at mature stage.In an attempt to clarify the significance of characteristics of bacterial populations in aged microcosms, the growth rates of bacteria were investigated. Bacteriafrom the microcosms were subjected to serial transfer at 3 d intervals in both single and two-species culture. Selection in single species populations under serial transfer favored an increased growth rate. When selection was applied to mixed populations, the growth rates of both species did not change or were sometimes reduced from that of parental strain. These results can be viewed as evidence for a trade-off between interspecitic competitive ability and growth rate.Selection was applied to adapting bacterial populations in two ways: in high nutrient (Bac-H) and low nutrient (Bac-L) medium. The growth rate of Bac-L was higher than that of Bac-H in low nutrient medium and the growth rate of Bac-L was lower than that of Bac-H in high nutrient condition.

我们已经在闭合的微观斑点上进行了观察（媒介：空气= 2：1），当时在25 d培养时用橡胶塞子塞入烧瓶时，它没有与大气交换。封闭的缩影中溶解氧的种群密度和硫化氧的变化与对照缩影中的氧气密度相同，对照缩影将气体与大气交换。气体氧的浓度几乎在闭合的微观上是恒定的。因此，在成熟阶段完全关闭了小型关闭后，可以保持人口密度和社区代谢活性水平。在尝试阐明细菌种群在老年微观上的特征的重要性，研究了细菌的生长速度。细菌从缩影均以单个和两个物种培养的间隔进行连续转移。在串行转移下的单个物种种群中的选择有利于增长率提高。当选择对混合种群中进行选择时，这两种物种的生长速率均未变化或有时从父母菌株中降低。这些结果可以看作是规范竞争能力和增长率之间取舍的证据。选择用于以两种方式适应细菌种群：在高营养（BAC-H）和低营养（BAC-L）培养基中。在低营养培养基中，BAC-L的生长速率高于BAC-H的生长速率，而在高营养条件下，BAC-L的生长速率低于BAC-H的生长速率。

项目成果

S. Shikano; Y. Kurihara: "Analysis of factors controlling responses of an aquatic microcosm to organic loading." Hydrobiologia. 169. 251-257 (1988)

S.鹿野；

S.Shikano: Hydrobiologia. 169. 251-257 (1988)

S.Shikano：水生生物学。

S.Shikano;Y.Kurihara: Yydrobiologia. (1988)

S.Shikano；Y.Kurihara：Yydrobiology。