养殖海带、裙带菜根部附着力初步研究

Holdfast Adhesion of Cultured Kelp Saccharina japonica and Sea Mustard Undaria pinnatifida

选取我国北方沿海大型藻类主要养殖品种海带、裙带菜,通过水流冲击法及拉力计测试法,测量两种藻类不同生长阶段根部附着力大小,并初步分析其附着能力。试验结果显示,海带、裙带菜苗绳上幼苗脱落率与水流速度有明显的对数关系,海带与裙带菜之间差异显著(P<0.05)。海带幼苗脱落率(y)与水流速度(x)关系式为y=0.2384lnx-0.5556,相对附着系数为0.0329;裙带菜苗绳上幼苗脱落率与水流速度关系式为y=0.2795lnx-0.769,相对附着系数为0.0419,同规格裙带菜幼苗附着能力强于海带。成体海带、裙带菜根部最大承受力与藻体本身全长及湿质量等各项指标均显著相关,海带、裙带菜根部附着力随着藻体规格的增长而增大,同规格裙带菜附着力显著高于海带(P<0.05)。根据试验结果,建议在幼苗时期尽量减缓水流速度,流速<20cm/s,以避免幼苗大量死亡,当幼苗生长至一定规格后,适当增加水流速度,以保证藻体良好发育。

The holdfast adhesive ability and adhesive force were measured in principally cultured kelp Saccharina japonica and sea mustard Undaria pinnatifida with body length of 1-10 mm in northern coast in China during different growth stages by means of water blast method and tensiometer test method.The results showed that there was a signficant logarithmic relationship between expulsion rate of the seedlings of S.japonica and U.pinnatifida and flow velocity,with significant difference between kelp and sea mustard(P<0.05).The relationship formula between the expulsion rate(y)of the kelp seedlings and the flow velocity(x)was expressed as y=0.2384ln x-0.5556,with a relative adhesive index of 0.0329.The relationship formula between the expulsion rate of the seedlings of sea mustard and the flow velocity was described as y=0.2795ln x-0.769,with a relative adhesive index of 0.0419,stronger adhesive ability in sea mustard seedlings than that in kelp.The maximal bearable force of the holdfast of adult kelp and sea mustard was shown to be closely related to all indices including the length and wet weight of frond,and their adhesive force was increased with the increase in size of the frond,with significant higher adhesive force in sea mustard than in the kelp within the same size(P<0.05).In conclusion,it is suggested that the flow velocity be reduced to less than 20 cm/s in the seedling period to avoid a large number of dead seedlings,and increased properly to ensure the good development of the macroalgae as they grow to a certain size.