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河口海岸环境变异和资源可持续利用 总被引：15，自引：2，他引：15
河口海岸是地球四大圈层交汇，能流和物流的重要聚散地带，中国入海河流众多，河流挟带泥沙每年达20亿t，占全世界入海泥沙的10%，植被破坏，水土流失，人类对水资源的开以及跨流域调水都能影响流域来水来沙，地下水超采也可以使河口海岸沉降，这些都影响着河口海岸的环境，该区域经济发达，人口集中，开发程度高，导致严重的环境变异，资源破坏，对区域持续发展造重大影响，特别是我国流域高强度开发对河口和邻近海域有直接和深远的影响。因此，开展河口海岸环境变异的研究，为解决国家目标和海岸带资源可持续利用是非常重要的。 相似文献
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The oceans are in trouble. Poorly understood and unprecedented environmental and economic changes are underway in our world's oceans that will significantly affect life in the sea as well as on land. Only in the last thirty years has the contribution of the ocean sector to the economy been measured. An examination of these studies has exposed definitional, conceptual and methodological differences in measuring marine-related economic activity in the economy, making comparisons difficult. Both the ocean and the coastal economies face a world of volatile changes. In the ocean economy marine transport faces unpredictable fuel costs. Coastal tourism also faces losses from climate change impacts and sea level rise. Finally, a warming ocean and increasing acidification of the oceans from greenhouse gases is already affecting coral reefs and a range of fish stocks. Economic measures are important to predict these impacts, as are economic measures of the resilience of different areas of the ocean and coastal economies. This article demonstrates how knowledge of both the ocean, coastal and national economies can help governments address the future impacts and demands posed by nature and human populations on our coasts and oceans. 相似文献
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本文阐述了生物海洋学的内容及其研究状况。根据我国沿海特点,建议我国今后对生物海洋学研究的重点是:1.对不同水域初级生产力的研究。2.对沿海小型底栖生物在海洋生态系统能流和物质循环中的作用研究。3.河口,有代表性海域可溶性有机物(DOM)、颗粒有机物(POM)的来源、数量分布、化学组成,以及在海洋食物链的作用和鱼虾产卵场变动关系的研究。4.沿海养殖环境生原要素循环、环境容量及病害发生的环境研究。5.海洋生物对重要有机污染物和海藻毒素的吸收、富集、代谢、在食物链传递,以及生态影响和生态监测研究。6.沿海植物性碎屑向近海输运,及其在食物链中的作用研究。7.浮游生物的群集、支配群集因素,以及和渔业关系的研究。8.选择代表性海域开展物质通量的研究。 相似文献
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长江口细颗粒泥沙絮凝作用及其制约因素研究 总被引：14，自引：1，他引：13
简要介绍了人海河口细颗粒泥沙的絮凝机理;以长江口细颗粒泥沙絮凝作用的研究为例,概述了影响河口细颗粒泥沙絮凝的若干因子;着重介绍了长江口水体生物地球化学过程对于细颗粒泥沙絮凝作用影响的研究进展。在此基础上,结合国内外相关研究的最新进展以及河口工程与环境中的泥沙问题,提出未来工作设想。 相似文献
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This paper describes the coastal system between Cape Palmas bordering the Ivory Coast and Liberia and Mount Cameroon, as a basis for regional coastal-erosion management.The area includes the rocky coasts of the Ivory Coast and Ghana, the long sandy beaches of Togo and Benin and the deltas of the Volta and Niger Rivers. Important elements of the system appear to be its geographical setting, its geological history, oceanological impacts, the sediment supply by rivers and coastal erosion, littoral transport and the rise of mean sea level. The morphological processes are influenced by human activities in the catchments of the rivers (dams), in the estuaries (dredging) and along the coasts (port construction).It appears that future human interventions and the impact of increased sea-level rise will require intergovernmental co-ordination in coastal-erosion management, as the various coasts are all part of one system. 相似文献
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Biomarker is an important tool in the study of marine organic geochemistry. Its development and application makes it possible to elucidate the process and mechanism of the organic matter in the ocean. Hydrocarbons are the most useful molecular markers. They are used as tracers in many aspects, such as source indication; the degradation of organic matter; diagensis process; environmental pollution and paleooceanic study, etc. They are studied in the estuaries,coastal area and deep sea to give the knowledge of marine organic geochemistry. The paper deals with the characteristics, development and application ofbiomarkers as well as their advantages and disadvantages. 相似文献
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选择厦门市海沧化工园区为典型案例区，以二甲苯为研究对象，采用数值模拟技术，对海岸带化工园区化学品泄漏的环境风险与生态效应进行了预测和识别，评估了海洋生态服务功能、水质、生物、潮滩生境4种对象的价值损失．结果表明，泄漏地点、风向、潮时以及泄漏量是影响化学品泄漏环境风险差异的主要因素．当泄漏量较小、泄漏点靠近化工泊位时，E风低潮时对海洋生态影响最大，此时最大生态价值损失约为3994万元；当泄漏量较大、泄漏点位于靠近外海的船舶锚地时，SSW风高潮时对海洋生态影响最大，生态价值损失最大为18732万元．在4种对象中，生态服务功能损失和生物损失对价值损害的贡献最大． 相似文献
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对于养殖用海集约利用评价,目前国内相关研究还非常缺乏。文章借鉴现阶段耕地集约利用的研究方法,结合养殖用海特征,对养殖用海集约利用内涵进行了界定,从海域利用程度、海域投入强度、海域利用效益、海域利用可持续性4个层面遴选10项指标建立了养殖用海集约利用评价指标体系,并以2016年为数据年份,选取我国9个沿海省、市、自治区进行区域养殖用海集约利用评价分析。结果显示,我国养殖用海集约利用整体处于较低水平,暂无高度集约利用省份,福建、广西、天津、山东等地处于相对集约状态,并从各准则维度进行了细化分析,提出优化利用方向。 相似文献
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Li Congxian 《海洋学报(英文版)》1993,12(4):573-584
-On the basis of the data obtained from the investigations on some rivers in China and Australia, the author discusses the spatial and temporal changes of various portions of fluvial-estuarine system during postglacial sea-level rising in present coastal and deltaic areas. The evolution of a fluvial-estuarine system can be divided into four development stages: early transgression, late transgression, stationary and regression. Early transgression brought about filling-in of the paleo-valley formed in low stand of sea level. In response to late transgression the estuaries were created, during the stationary stage the big swamp was developed. The regression led to estuaries to be filled with sediments and then became deltas. At the same locality the fluvial-estuarine system changed with time. In the transgressive period the lower reach of a river changed into an estuary, and then became nearshore area. In the regressive period the nearshore area changed into an estuary , and then became delta. 相似文献
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S. O. Razumov 《Oceanology》2010,50(2):262-267
Some regularities that are generally accepted in the theory about the development of sea coasts as applied to the East Arctic
coast of Russia do not conform to reality. To find out the reasons for these contradictions, the connection between the coastal
processes and the perennially frozen sediment of the underwater coastal slope in the Laptev Sea and the East Siberian Sea
was studied. The frozen state of the deposits of the coastal zone exerts a substantial influence on the coastal dynamics and
determines several features of the thermoabrasion development. In particular, the subaqual permafrost does not allow the forming
of a storm profile with dynamic balance. This fact causes the more effective action of the sea on the coastal cliffs and the
more active recession of the frozen coasts as compared with their counterparts outside the cryolitozone. 相似文献
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北冰洋西伯利亚陆架海是北极气候快速变化最为显著的海域之一,而沉积硅藻作为极地海洋生态系统的重要组成部分,对环境变化具有敏感的响应。对楚科奇海、东西伯利亚海和拉普捷夫海表层沉积物开展了硅藻组成鉴定,利用典型对应分析方法分析了硅藻属种与1986～2015年环境变量之间的关系。结果表明,夏季和秋季海冰密集度、表层海水盐度是影响研究区表层硅藻分布特征最主要的因素。此外,根据表层站位与环境变量的典型对应分析,可将西伯利亚极地海域划分为4个区域,分别为海冰硅藻组合带、暖水硅藻组合带、沿岸硅藻组合带和混合硅藻组合带。这些表层站位的分区与相应区域的海流模式有明显的相关性,海冰硅藻组合带仅分布于研究区北部的高纬度地区;暖水硅藻组合带位于受白令水和太平洋海水的分支——阿拉斯加沿岸水影响为主的区域;拉普捷夫海南部的沿岸硅藻组合带则受到河流径流和西伯利亚沿岸流的强烈影响;混合硅藻组合带受极地冷水、海冰覆盖、太平洋暖水和陆地径流的共同影响。 相似文献