汕头南澳海域不同养殖区浮游纤毛虫群落结构的比较

A comparative study on community structure of planktonic ciliates in different mariculture areas of Nan'ao Island in Shantou City

为比较不同海水养殖模式对纤毛虫原生动物群落结构和水环境的影响,于2014年4—6月,对汕头南澳海域鱼类养殖区、贝类养殖区、大型海藻龙须菜栽培区和自然水体（对照海区）的纤毛虫和主要水质指标进行了每3~4 d一次的高频次监测,并应用沉积物捕捉器研究了纤毛虫包囊的沉降通量。结果表明：调查区域共发现纤毛虫17种,纤毛虫丰度为75~150 ind·L-1,对照海区和鱼类养殖区内纤毛虫丰度变化相对剧烈;龙须菜栽培区纤毛虫功能群中食藻者所占比例达50%;鱼类养殖区纤毛虫包囊沉降通量最高,平均沉降1.9×104cysts·d-1·m-2,显著高于对照海区和龙须菜栽培区;不同养殖区水体纤毛虫群落结构与沉积物中包囊群落结构有较大差异,龙须菜栽培区纤毛虫群落结构最稳定。

To compare the impacts of mariculture modes on ciliate community structure and aquatic environment, an investigation was carried out to analyze the ciliate and the main indexes of water quality in a natural water （control） and the areas with different modes of mariculture, i.e. finfish, shellfish and seaweed （Gracilaria） , in the Nan＇ ao coastal waters of Shantou City in South China. Surface water and sediment samples were collected from each site once every 3-4 days from April to June, 2014. Deposition flux of cysts was studied with sediment traps. A total of 17 species of ciliates were recorded at the four sites and the range of ciliate abundance was 75- 150 ind ·L-1. The community structure of planktonic ciliates in seaweed cultivation area was rich and diverse compared to the fish, shellfish and control areas based on the ciliate abundance and species diversity. The highest densities of ciliate cysts were found in the sediment of the fish- farming area, with an average of 1.9×10^4 cysts · d-1 · m-2, compared to the other areas. The re- sults indicated that there existed a great difference in the community structure of the ciliates in the waters and the cysts in the sediments among different mariculture sites, and the ciliate com- munity structure was more stable in the seaweed cultivation area compared to the other maricul- ture areas.