大亚湾及大鹏半岛沿岸造礁石珊瑚现状与生态脆弱性评价

Status of scleractinian corals in Daya Bay and along the coast of Dapeng Peninsula and ecological vulnerability assessment

本研究于2020年7月在大亚湾及大鹏半岛沿岸开展造礁石珊瑚的分布、覆盖率、死亡率、硬珊瑚补充量和物种多样性调查。结果表明:24个站位共发现造礁石珊瑚9科17属44种以及5个未定种,其中裸肋珊瑚科的种类最多,有7属27种,其次为鹿角珊瑚科和滨珊瑚科,均有2属6种;中央列岛沿岸造礁石珊瑚平均覆盖率为12.0%,三门岛沿岸平均覆盖率为12.9%,大鹏半岛沿岸平均覆盖率为5.2%;以坚实滨珊瑚(Porites solida)、翼形蔷薇珊瑚(Montipora peltiformis)、五边角蜂巢珊瑚(Favites pentagona)和多孔同星珊瑚(Plesiastrea versipora)等为优势种;造礁石珊瑚物种多样性较高。与历史数据相比,大亚湾及大鹏半岛沿岸造礁石珊瑚退化严重,活珊瑚覆盖率锐减,优势种由分支状珊瑚逐步转变为皮壳状或亚团块状珊瑚。此外,本研究构建了近岸造礁石珊瑚生态脆弱性评价体系,并对目前大亚湾及大鹏半岛沿岸造礁石珊瑚进行了生态脆弱性评价。结果显示,中央列岛、三门岛和大鹏半岛东侧海域造礁石珊瑚处于低或中脆弱状态;较场尾、杨梅坑、西冲和大鹏半岛西侧海域造礁石珊瑚处于高或很高脆弱状态,在环境压力影响下其受损可能性较高。在海水养殖、渔业捕捞、滨海旅游和船舶航行等日益频繁的人类活动下,大亚湾及大鹏半岛沿岸造礁石珊瑚整体处于中高脆弱状态,建议加强珊瑚礁监测,并采取相应的保护措施。

In this study,we investigated the distribution,coverage,mortality,recruitment and diversity of scleractinian corals in Daya Bay and along the coast of Dapeng Peninsula in July 2020.Results showed that 44 species and 5 undetermined species of scleractinian corals,belonging to 17 genera and 9 families,were found at 24 sites.Among them,Merulinidae,including 27 species and 7 genera,had the most diversified species,and followed by Acroporidae and Poritidae,both including 6 species and 2 genera.The average coverage of scleractinian corals was 12.0%,12.9%and 5.2%along the coast of Central Islands,Sanmen Island and Dapeng Peninsula,respectively.Porites solida,Montipora peltiformis,Favites pentagona and Plesiastrea versipora were the dominant species,and the species diversity of scleractinian corals was relatively high.Compared with the historical data,scleractinian corals in Daya Bay and along the coast of Dapeng Peninsula were severely degraded,the living coral coverage decreased sharply,and the dominant species gradually changed from branching corals to encrusting or massive corals.In addition,this study constructed an assessment system for the ecological vulnerability of scleractinian corals in these coastal areas.It showed that scleractinian corals around the coastal areas of Central Islands,Sanmen Island and east side of Dapeng Peninsula were in low or medium vulnerary state.The corals at Jiaochangwei,Yangmeikeng,Xichong and west side of Dapeng Peninsula were in high or very high vulnerary state,and they were more likely to be damaged under environmental pressure.With the frequent strengthened human activities such as mariculture,overfishing,coastal tourism and ship navigation,the scleractinian corals in Daya Bay and along the coast of Dapeng Peninsula become highly vulnerable.It is necessary to strengthen coral reef monitoring and take corresponding protection measures.