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11月22日,由中国海洋学会、中国太平洋学会和河北省海洋局共同主办的第六届海洋强国战略论坛在石家庄市隆重召开。本届论坛以"保护渤海环境,推动海洋生态@明建设"为主题,提出举科学之力、聚专家之智,共同探讨海洋强国的战略内涵,探索决策海洋强国的理论,寻求建设海洋强 相似文献
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1997年7月,联合国教科文组织通过了将“海洋——人类的共同遗产”作为“国际海洋年”的主题的建议,要求各国以各种形式积极参与国际海洋年的活动,并将7月18日定为“世界海洋日”。 相似文献
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所谓生物多样性是指地球上所有的生物体及其所构成的综合体,它包括遗传多样性,物种多样性和生态系统多样性三个层次。换句话说,生物多样性是生物和它们组成的系统的总体多样性和变异性。生物多样性是地球生命数十亿年发展进化的结果,它是人类赖以生存和持续发展的物质基础。
但是,随着环境不断遭受破坏,森林砍伐、植被破坏、滥捕乱猎、污染频发,据估计,目前世界上的生物物种正在以每小时一种的速度消失。而自然物种一旦消失,就不会再生。更可怕的是,生物物种的消失,不仅仅是单一自然资源的损失,还会引起一系列连锁反应,从而影响其他物种的生存。 相似文献
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红树林海岸的沉积物输运和碳沉降特征 总被引:1,自引:0,他引:1
Mangroves play an important role in sequestering carbon and trapping sediments. However, the effectiveness of such functions is unclear due to the restriction of knowledge on the sedimentation process across the vegetation boundaries. To detect the effects of mangrove forests on sediment transportation and organic carbon sequestration, the granulometric and organic carbon characteristics of mangrove sediments were investigated from three vegetation zones of four typical mangrove habitats on the Leizhou Peninsula coast. Based on our results, sediment transport was often "environmentally sensitive" to the vegetation friction. A transition of the sediment transport mode from the mudflat zone to the interior/fringe zone was often detected from the cumulative frequency curve. The vegetation cover also assists the trapping of material, resulting in a significantly higher concentration of organic carbon in the interior surface sediments. However, the graphic parameters of core sediments reflected a highly temporal variability due to the sedimentation process at different locations. The sediment texture ranges widely from sand to mud, although the sedimentary environments are restricted within the same energy level along the fluvial-marine transition zone. Based on the PCA results, the large variation was mainly attributed to either the mean grain size features or the organic carbon features. A high correlation between the depth and δ13C value also indicated an increasing storage of mangrove-derived organic carbon with time. 相似文献
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