通过对广东沿海水域的现场调查, 新发现8个海草床, 主要分布在柘林湾、汕尾白沙湖、惠东考洲洋、大亚湾、珠海唐家湾、上川岛、下川岛和雷州企水湾。海草种类主要包括喜盐草(Halophila ovalis)、贝克喜盐草(Halophila beccarii)和矮大叶藻(Zostera japonica)等3种。海草覆盖率为6.67%—53.33%, 茎枝密度为3 428.57— 10 542.00shoots.m-2, 生物量为12.86—118.24g.m-2。海草床底上生物密度为16.67—734.67ind.m-2, 生物量为15.39—426.88g.m-2, 多样性指数为0.46—1.98, 均匀度指数为0.28—0.89。海草床生境受到的严重威胁主要来自围海养殖(养蚝、养螺)、污水排放、渔民作业方式(电鱼、电虾、扒螺、挖贝类)、自然灾害(台风和洪水)等。

Distribution, species composition, biomass, habitat of seagrass beds and main threats that seagrass bed habitats suffer are introduced and discussed in this paper based on field surveys in the offshore areas of Guangdong Province. The newly-discovered seagrass beds mainly distribute in the Zhelin Bay, Baisha Lake, Kaozhouyang Lagoon, Daya Bay, Tangjia Bay of Zhuhai, Shangchuan Island, Xiachuan Island, Qishui Bay of Leizhou and so on. There are three species of seagrass, namely Halophila ovalis, Halophila beccarii and Zostera japonica. Percentage coverage, shoot density and biomass of sea-grass are 6.67%-53.33%, 3 428.57-10 542.00shoots.m-2 and 12.86-118.24g.m-2, respectively; while mean density, biomass, diversity and evenness index of benthic organisms on seagrass beds are 16.67-734.67ind.m-2, 15.39-426.88g.m-2, 0.46-1.98 and 0.28-0.89, respectively. However, the seagrass habitats are subjected to some threats resulted from artificial and natural causes, such as culture of oysters and snails, wastewater discharge, fishing by means of electric power, shellfish collection, typhoons and floods.

广东省908项目(GD908-01-03, GD908-02-11); 国家自然科学基金(40776086); 中国科学院南海海洋研究所知识创新工程领
域前沿项目(LYQY200706)

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