| 摘要: |
| 综合2007 年10～11 月、2008 年4～5 月布置的6 条主剖面20 条分断面的调查结果, 涠洲岛珊瑚礁共出现石珊瑚10 科22 属46 种, 9 个未定种, 该调查区以角蜂巢珊瑚属(Favites)、滨珊瑚属(Porites)、蔷薇珊瑚属(Montipora)为优势类群, 各主剖面的优势类群分布各有差异, 以西南部的W2 主剖面、东北部的W5 主剖面的珊瑚礁属种最多, 均为8 科13 属; 涠洲岛珊瑚礁属级多样性指数H′值和均匀度指数E 值均呈现东北部W5＞西南部W2＞东南部W6＞西南部W1＞西北部W3＞北部W4 的规律, H′值差异明显, E 值变化不大; 其珊瑚礁群落近20 a 来受到全球气候事件及区域人为活动的影响, 整体呈现出衰退迹象, 处于缓慢恢复状态。衰退表现在: 从20 世纪60 年代至21 世纪初期的珊瑚礁优势种群的组合变化, 由较多的优势属种组合演化到相对少的优势属种组合。一直占据优势的鹿角珊瑚种群出现退化, 从顶级优势类群降级更替; 珊瑚礁属种的多形态组合向相对简单形态组合的演变; 历年来珊瑚礁伴生生物的资料(主要是鱼群数量、海参等)显示, 涠洲岛珊瑚礁群落生物多样性呈现衰退态势; 从2001年至今连续的珊瑚礁健康调查(Reef Check)资料显示, 该区石珊瑚礁曾大面积死亡尚未完全恢复。从涠洲岛20 a 珊瑚礁多样性演变过程研究发现, 影响因素主要包括全球性极端气候、区域性气候变化及不合理的破坏性人类活动影响等因素。 |
| 关键词: 涠洲岛 珊瑚礁 生物多样性演化 全球变化 区域性气候变化 人类活动 |
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| 基金项目:广西科学研究与技术开发计划项目(桂科攻0992026-2); 广西科学院基本科研业务费资助项目(09YJ17HS01); 北海市科技局基础研究项目(北科合200601055); 广西908 专项资助项目(GX908-01-06);广西科学基金应用基础项目(桂科基0575025); 广西自然科学基金项目(0832070) |
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| Long-term changes of the coral reef biodiversity at the Weizhou Island, Beihai, Guangxi |
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| Abstract: |
| A comprehensive investigation of coral reef at the Weizhou Island, conducted during October-November 2007 and April-May 2008 with 20 sampling subsections in six principal sections, had found 55 species distributing around the island with 46 species being identified and 9 species unknown, belonging to 22 genera under 10 families. The dominant species in the entire island region were Favites, Porites, and Montipora, while the distribution of the dominant species in each investigated principal section varied from one another. In W2 in the southwest and W5 in the northeast, there was found in number the largest genera and species, including 13 genera under 8 families. The species diversity indices at the genus-level H′ and evenness indices E of coral reef in the island showed a trend of W5 in the northeast＞W2 in the southwest＞W6 in the Southeast＞W1 in the Southwest＞W3 in the northwest＞ W4 in the North. The diversity indices varied greatly while the evenness indices exhibited few changes. In recent 20 years, coral reef in the island had showed a sign of degradation on the whole due to the global climate change and local fishing activities. The degradation reflected in the fewer and fewer combination pattern of dominant genus and species from 1960s to the early 21st century. The acropora group, for example, once among the dominant species, was degraded and was replaced; the composition pattern of both genus and species had also changed from the complex multi-components in the past to the simple mono-ones at present; according to the historical data of organisms associated with coral reef (mainly about the species of fish and sea cucumbers), the biodiversity of coral reef community in Weizhou Island had showed a tendency of degradation. According to the data of consecutive Reef Check from 2001 to the present, there has been a massive death of corals at the island, the influence of which has not been uncovered yet. Research on the evolution process of the coral reef diversity in Weizhou Island over the past 20 years has indicated that the influencing factors include global extreme climate, regional climate change and irrational, and destructive human activities. |
| Key words: Weizhou Island coral reef biodiversity change global change regional climate change human activities |
