Growth and reproduction of migrating and non-migrating Daphnia species under simulated food and temperature conditions of diurnal vertical migration
Growth and reproduction of migrating and non-migrating Daphnia species under simulated food and temperature conditions of diurnal vertical migration
复制标题
洄游和非洄游水蚤在模拟昼夜垂直洄游的食物和温度条件下的生长和繁殖
作者：
H. Stich;W. Lampert
（1）在流动系统中研究了博登湖两种水蚤对恒定和波动的温度和食物条件的生长响应。(2)In湖D。hyalina表现出明显的昼夜垂直迁移模式，而D.盔状星云停留在地表附近实验的目的是测量生长和繁殖成功的物种的条件下，他们所经历的同行在外地。（3）两种物种在“非迁移”条件下（持续高温和高浓度食物）生长更好，产生更多的后代。因此，垂直迁移没有代谢优势。（4）D. hyalina比D. galeata在极端“迁徙”条件下（高食物水平/夜间高温和极低食物水平/白天低温），D.在有利条件下，盔状花序生长稍好。（5）这一结果不支持水蚤类通过垂直迁移获得代谢优势的假说。
Summary(1)The growth response of two Daphnia species coexisting in Lake Constance to constant and fluctuating conditions of temperature and food was tested in a flowthrough system.(2)In the lake D. hyalina exhibits a pronounced diurnal pattern of vertical migration, whereas D. galeata stays near the surface. The experiments were designed to measure growth and reproductive success of the species under the conditions as they are experienced by their counterparts in the field.(3)Both species grow better and produce more offspring under “non-migration” conditions (constant high temperature and high concentration of food). Thus there is no metabolic advantage by vertical migration.(4)D. hyalina is more successful than D. galeata under extreme “migration” conditions (high food level/high temperature at night and very low food/low temperature during day), but D. galeata grows slightly better under favourable conditions.(5)The results do not support the hypothesis that daphnids gain some metabolic advantage from vertical migration.