瓦氏马尾藻规模化繁育技术研究

研究了瓦氏马尾藻(Sargassum vachellianum)规模化育苗及海区养殖技术。采集海区成熟藻体, 室内催熟放散受精卵, 收集并喷洒于水泥板、棕绳、木板3种附着基, 进行受精卵附着、萌发及苗体生长等实验, 发现棕绳育苗效果最佳。受精卵喷洒10d后, 3种附着基的出苗率分别为 85.5%、80.2%和91.3%, 平均株高约1.3 mm。前20天木板幼苗密度最高, 达8.2株/cm2, 但幼苗均生长缓慢。第30天, 幼苗出现明显分枝, 生长率增大到前20天的1.6倍, 其中棕绳幼苗株高最大, 幼苗存活率分别为83.6%、79.7%和75.6%。第60天棕绳幼苗密度及平均株高均最大。将附有幼苗的水泥板(藻礁)、棕绳放入海区进行养殖, 发现幼苗在浪大流急海区生长较快, 4周后平均株高分别达98.7和103.1 mm, 是对照组的1.5倍, 但棕绳脱苗严重。藻礁较适合海区规模化投放养殖, 是藻场修复和重建的理想材料。

STUDIES ON THE LARGE-SCALE BREEDING OF SARGASSUM VACHELLIANUM

In this study, we optimized the technology of the large-scale seeding and breeding of Sargassum vachellianum in the sea water. The mature algae were collected from the sea water and then were stimulated to spawn the fertilized eggs. These eggs were collected and sprayed onto the substratum surface of the floor slab, the coir rope and the plank for the further settlement, germination and growth. The results suggested that the coir rope was the most efficient for seeding. Ten days after the spraying, the germination rates on the three substrates were 85.5%, 80.2% and 91.3% respectively, and the average height was 1.3 mm. On the 20th day, the plank-attached seedlings showed the highest density of 8.2 cells/cm2, but the growth was slow. On the 30th day, the branches of the seedlings appeared and the growth rate was 1.6 times higher than that on the 20th day. The height of seedlings on the coir rope was the greatest and the survival rates on the three substrates were 83.6%, 79.7% and 75.6% respectively. On the 60th day, the coir ropeattached seedlings showed the highest values in density and in the average height. When transferred into the sea water, the floor slab (algal reef)-and coir rope-attached seedlings grew faster in the turbulent and torrential area. After 4 weeks, the average heights of plants on the floor slab and the coir rope were 98.7 mm and 103.1 mm respectively, which was 1.5 times higher than the control group. However, the seedlings on the coir rope could be easily washed away in the sea water. In conclusion, the algal reefs could be the suitable substrate for the large-scale farming and they may also be an ideal material for the repair and reconstruction of the algae bed.