环流型水域水动力对藻类生长的影响

Influence of circumfluent type waters hydrodynamic on growth of algae

实验模拟了不同风浪强度、不同营养水平下铜绿微囊藻的生长速率.选取能代表湖流和波浪综合作用的综合摩阻流速作为太湖水动力的表征指标,建立藻增长率和综合摩阻流速关系.结果表明,低、中营养水平下的藻类受扰动的影响规律较为接近,90r/min扰动时生长最好;而高营养水平下的藻类受扰动影响差异不明显.营养盐对藻类的生长影响较大,扰动可以改变由营养水平不同所引起的藻类生长的差异.铜绿微囊藻在低、中营养水平下生长时最优综合摩阻流速约为0.133cm/s.藻增长率随着综合摩阻流速呈现先指数递增、后指数递减的规律.湖泊环流型水域和河道径流型水域水动力作用存在明显差异.

The growth rate of Microcystis aeruginosa under different wind wave strength and different nutrient levels was test simulated. The comprehensive friction flow velocity, which is capable of representing the lake current and wave, was selected Lake Taihu hydrodynamic express index. The relation between algae growth rate and comprehensive friction velocity was established.The influence laws of algae kind disturbance under low and medial nutrient levels were similar. The growth was best when the disturbance was 90r/min, and the influence of algae kind disturbance under high nutrient level varied unobviously. Nutrient had major influence on algae kind growth. The disturbance could change the algae growth variation induced by different nutrient levels. Microcystis aeruginosa in low and medial nutrient levels was most prior： comprehensive friction flow velocity was about 0.133 cm/s, the algae growth rate appeared first index increased by degrees than decreased by degree law with comprehensive friction flow velocity. Lake circumfluent type waters and rivers runoff type waters hydrodynamic action existed obvious variation.