荣成近岸养殖海域浮游植物群落结构及与环境因子的关系

Influence of Environmental Factors on Phytoplankton Community Structure and Its Relationship with Coastal Aquaculture in the Waters Adjacent to Rongcheng

中文关键词: 养殖海域  浮游植物  群落结构  环境因子  典范对应分析

英文关键词: Aquaculture waters  Phytoplankton  Community structure  Environmental factors  Vanonical correlation analysis

中文摘要:

      基于2016年4个季节的生态调查数据，研究了山东荣成近岸养殖海域浮游植物群落结构，同时，应用典范对应分析(CCA)讨论了环境因子对荣成近岸养殖海域浮游植物群落结构的影响。4个季度共发现浮游植物66种，分隶于硅藻、甲藻及金藻3个植物门、29个属；浮游植物优势种包括中肋骨条藻(Skeletonema costatum)、具槽直链藻(Melosira sulcata)、日本星杆藻(Asterionellopsis glacalis)、扭链角毛藻(Chaetoceros tortissimus)、尖刺菱形藻(Nitzschia pungens)及劳氏角毛藻(Chaetoceros lorenzianus)，具有明显的季节演替现象。春季日本星杆藻在荣成湾大量出现使其成为优势种。4个季节浮游植物丰度变化范围为(16.9~251.7)× 104 cells/m3，平均为119.3×104 cells/m3，以夏季最高，秋季最低；全年浮游植物多样性指数(H)、均匀度指数(J)、丰富度指数(d)和优势度指数(D2)的变化范围分别为1.60~2.13、0.40~0.60、0.58~0.79和0.70~ 0.84，多样性指数以夏季最高，冬季最低，但均处在较好水平；CCA分析结果表明，海水溶解氧(DO)、硅酸盐(SiO32–-Si)、铵盐(NH+4)、温度和pH等环境因子为影响该海域浮游植物群落结构的主要因子，除了季节影响因素以外，当地多元化的养殖模式可能是导致目前浮游植物群落结构的重要因素。

英文摘要:

      The phytoplankton community structure in the coastal aquaculture area of Rongcheng was analyzed based on the results of four surveys during 2016. The influence of environmental factors on the phytoplankton community in the Rongcheng coastal aquaculture area was discussed using canonical correlation analysis. The results identified a total of 66 species that belong to 29 genera of 3 phyla. The dominant species of phytoplankton include Skeletonema costatum, Melosira sulcate, Asterionellopsis glacalis, Chaetoceros tortissimus, Nitzschia pungens, and Chaetoceros lorenzianus with seasonal succession. In the spring A. glacalis increased quickly in Rongcheng Bay to make it the most important dominant species of this season, but not in Sanggou Bay, when compared with the results of previous studies. The abundance of phytoplankton varied from 16.9×104 to 251.7×104 cells/m3 over the 4 seasons, the average density of whole year was 119.3×104 cells/m3, which was the highest in summer and the lowest in autumn. The Shannon-Wiener diversity index and Pielou’s index range from 1.60 to 2.13 and 0.40 to 0.60, respectively, and the diversity of phytoplankton was the highest in the summer, and the mode of the phytoplankton structure changed with the seasons, but the levels of phytoplankton remained normal all year round. Canonical correlation analysis showed that the most important factors affecting phytoplankton community structure are dissolved oxygen, silicate, NH+4, sea surface temperature and pH. These may promote or inhibit the growth of specific species and cause the rise of dominant species. Large-scale kelp farming in the area changed the amount of nutritional salt, high density shellfish farming consumed the natural enemies of phytoplankton, and shellfish excretion also changed the composition of nutritional salts in the coastal waters; therefore, local aquaculture in the Rongcheng coastal waters may be an important factor in the pattern of phytoplankton community structure in addition to the influences of seasonal changes.