水动力条件对鼠尾藻幼苗生长的影响

Effects of Hydrodynamic Conditions on Growth of Sargassum thunbergii Seedling and Content of Chlorophyll-a

关键词:  水层深度  水流速度  特定生长率  叶绿素a

Key words:  water depth  water velocity water  the specific growth rate  chlorophyll-a

摘要:

[目的]考察水层深度和水流速度对鼠尾藻幼苗生长的影响。[方法]以特定生长率和叶绿素a含量为考查对象,设计水层深度和水流速度的单因子实验和双因子实验,研究鼠尾藻幼苗对水层和水流刺激的适应情况。[结果]鼠尾藻幼苗特定生长率在水层深度为-0.3 m时最高,过深的水层(水层深度为-1.5 m)不适合鼠尾藻幼苗的生长;特定生长率随着水流速度的增加而增加,在水流速度为0.9 m/s时最高,然后下降。鼠尾藻幼苗体内叶绿素a含量随着水层加深(0~-0.9 m)而不断积累增多,但是随着水层继续加深而相对减少,且其在低水流速度下含量较高,随着水流速度的升高呈下降趋势。[结论]较浅的培育水层和适度的水流速度条件对鼠尾藻幼苗生长有积极的影响。

Abstract:

[Objective] To investigate the effects of water depth and flow velocity on the growth of Sargassum thunbergii.[Methods] Taking the growth rate and the contents of chlorophyll-a as test objects, the single factor and two factors experiments were designed to study the adaptation of the water flow stimulation and different water layers to Sargassum thunbergii seedlings.[Results] The specific growth rate of Sargassum thunbergii seedlings was highest in -0.3 m water depth, and the Sargassum thunbergii seedlings didn't grow in the excessive water depth(in -1.5 m water depth). The specific growth rate increased when the water flow velocity increased. When the water flow velocity reached 0.9 m/s,the specific growth rate fell down.The chlorophyll-a contents of Sargassum thunbergii seedlings increased with the water depth declined(0~-0.9 m), and reduced when the water depth declined enough. The chlorophyll-a content was high in low water flow velocity, and declined with the water flow velocity increased.[Conclusion] The lower layer and moderate flow velocity show a positive impact on the growth rate of Sargassum thunbergii seedlings.