坛紫菜北方海区养殖试验

The cultivation experiments of Pyropia haitanensis in the northern coast of China

摘要:

为进一步拓展坛紫菜“南菜北养”的范围,2018年和2019年在山东烟台海区进行了坛紫菜“闽丰2号”的养殖试验。2018年9月中旬将购自江苏、幼苗肉眼可见的网帘投放下海,至12月上旬采收五水(第一次采收的紫菜叫头水或一水紫菜,后面的依次叫二水、三水、四水、五水),总产量为2 359.5 kg/hm²(干质量)；2019年8月下旬,采用坛紫菜成熟贝壳丝状体在当地进行采苗、下海,9月下旬进行一水紫菜的收获,至11月中上旬共采收五水,总产量为1 574.3 kg/hm²(干质量)。随着收获期的延长,藻体的长度、宽度均呈增加趋势,但2个年度产量分别以三水和四水为最高。海区营养盐测定结果表明:海水中的无机氮浓度随着养殖时间的延长呈降低趋势,10月份的无机氮浓度明显低于8月份的,晒网同时喷洒施肥后藻体颜色快速好转,且产量有所提高,表明试验海区营养盐条件是影响坛紫菜养殖的重要因素之一。为避免病害发生,在养殖过程中应及时施肥以促进藻体生长,提高坛紫菜的产量和质量。

Abstract:

The cultivation experiments of Pyropia haitanensis were carried out in Yantai Sea area,Shandong Province in 2018 and 2019 to expand the scope of its northward transplantation in China.The results showed that the cultivation nets of P. haitanensis,purchased from Jiangsu Province with the visible seedlings,were launched into the sea in mid-September 2018,and five times had been harvested by early December with a total yield of 2 359.5 kg/hm²(dry weight).The seedlings of P. haitanensis were bred and cultivated in late August 2019,and the first harvest started in late September.It had been harvested five times with a total yield of 1 574.3 kg/hm²(dry weight) by mid-to-early November.Both the length and width of P. haitanensis blades increased gradually with the extension of harvest time,but the yields were the highest in the third and fourth harvest in 2018 and 2019,respectively.The results of seawater nutrient showed a decreasing trend towards the concentration of inorganic nitrogen with the extension of harvest time,and its content in October was significantly lower than that in August.The color of P. haitanensis took a turn for better rapidly and the yield increased after fertilization.Those results showed that nutrient in this coast became one of important limiting factors for the farming of P. haitanensis,which would be liable to the occurrence of disease.Therefore,timely fertilization will promote the growth,yield and quality during the cultivation.