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HUANG Hui LIAN Jiansheng HUANG Xiaoping HUANG Liangmin ZOU Renlin WANG Daoru 《科学通报(英文版)》2006,51(B12):129-135
The Yongxing Island is the biggest island of Xisha Islands in the middle part of the South China Sea. It occupies 1.8 square kilometers of land area and has permanent residence on it. There are only a few papers on the coral community of the Xisha Islands, reporting the species composition, structure and zonations of the hermatypic coral community in 1970s. The present study describes the hermatypic coral community based on the quadrat survey after almost 30 years in Yongxing Island in August 2002. It was the first time to present the percent cover data of live corals of Yongxing Island via a systematic scheme of quantitative quadrat sampling. The average total percent cover of the live coral is 68.4%. We found the total percent cover (TPC) could be an idea proxy of the overall disturbance regime impinging on the coral community. TPC can be used as an integrated measure of disturbance to coral reef. Using this surrogate, the best fit relation between TPC of the live corals and species richness, species diversity, or the species evenness is the unimodal second-order polymorphic parabola equation. This result is expected by the intermediate disturbance hypothesis (IDH). From the fitted parabola equations, we calculated the best TPCs corresponding to the maximal species richness, the highest species diversity, or the most evenness respectively. They are surprisingly stabilized between 55% and 58%. Coral cover is the basic parameter widely available for most observation, research or monitoring programs. The good qualitative characteristics of percent cover provide powerful tool for the experimental, theoretical and modeling studies of coral reef in response to the disturbance. 相似文献
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地基遥感方法可以直接得到大气气溶胶的辐射特性,用于气溶胶粒子谱分布特征的研究。利用ASD地物光谱仪在永兴岛海洋站楼顶获取的太阳辐射实测数据,应用蒙特卡罗方法随机生成气溶胶4种组分比例近似求解消光方程来反演气溶胶粒子谱。结果表明,实验期间永兴岛气溶胶各组分比例与标准辐射大气模型中的海洋型气溶胶相似;体积谱为双峰分布,2个主峰分别位于0.01~0.1μm和1~10μm;数浓度谱为单峰分布,主峰位于0.001~0.01μm;数浓度和体积浓度变化规律与海水扰动、粒子的干湿沉降过程有关,与浑浊度指数相关性达98%以上,可用来表征大气浑浊程度。 相似文献
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报道了2002年8月对永兴岛造礁石珊瑚群落的调查结果.对西沙群岛的造礁石珊瑚进行系统的定量采样,平均活珊瑚覆盖率达68.4%.发现,活珊瑚的总覆盖率或无活珊瑚覆盖率可以作为干扰的综合代用指标.使用这个指标,活珊瑚的总覆盖率与多样性之间的最优拟合曲线总是如“中度干扰假说”所预言的为一个单峰上拱的二次曲线关系.并且对应于最高多样性的总覆盖率稳定在55%~58%之间.这一结果反映了环境稳定性(或干扰度)与多样性之间有趣的现象.珊瑚覆盖率对于许多珊瑚礁调查都是基本的参数.有大量的长期的数据积累,如果可以作为干扰的代用指标,可以更好地了解珊瑚对干扰的反应.普遍认为,干扰,尤其是人类活动的干扰,是目前生态学研究的中心问题.覆盖率所具有的良好的定量特性为珊瑚礁的实验、理论和建模研究提供了一个很好的利器. 相似文献
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西沙群岛:珊瑚为国土增色
西沙群岛像朵朵睡莲,珍珠般地浮在绿波万顷的中国南海上。它位于海南岛东南约333km处,与东沙、中沙、南沙群岛组成中国最南端的疆土。西沙群岛从东北向西南方向伸展,在长250km、宽约150km的海域里,由45座岛、洲、礁、沙滩组成。西沙群岛的东面为宜德群岛,由北岛、石岛和永兴岛等7个岛屿组成;西面是永乐群岛,由金银、中建、珊瑚等8个岛屿组成。西沙群岛地处北回归线以南, 相似文献
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