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西太平洋——我国深海科学研究的优先战略选区 总被引:2,自引:0,他引:2
西太平洋是我国实施由浅海向深海发展战略的必经之地.从国家需求的角度来看,西太平洋海底资源丰富、海洋环境复杂,是维护国家权益的焦点、保障国防安全的屏障;从科学前沿的角度来看,西太平洋发育有独特的沟弧盆构造体系和弧后盆地热液系统,存有海底板块运动的遗迹和众多海山生态系统,更是"大洋传送带"冷暖水系的转换区.科学有序地进入西... 相似文献
634.
苏北盆地溱潼凹陷殷庄—台兴区块阜宁组三段自上而下分为Ⅰ、Ⅱ、Ⅲ、Ⅳ4个砂组,沉积相组合为三角洲前缘相——包括前缘近端坝、远端坝、分流间湾相砂体夹浅湖—半深湖相泥岩互层。各砂组在分布上具有不同的形态。广山、殷庄、台兴、戴南地区发育的三角洲前缘近端坝和远端坝为有利储集相带。 相似文献
635.
长江三角洲地区生态足迹的时空动态及其可持续发展分析(英文) 总被引:3,自引:0,他引:3
In the urbanizing world,the Yangtze Delta Region (YDR) as one of the most developed regions in China,has drawn a lot of the world’s attention for the remarkable economic development achieved in the past decades.Nevertheless,the rapid economic development was certain to be accompanied by unprecedented consumption and loss of natural resources.Therefore,the analysis of the ecological situation and driving factors of environmental impact was of great significance to serve the local sustainable development decision-making and build a harmonious society.In this paper,the ecological footprint (EF) was taken as the index of the ecological environmental impact.With the help of Geographic Information System (GIS),we studied the spatiotemporal change of ecological footprint at two scales (region and city) and assessed urban sustainable development ability in YDR.Then we discussed the driving factors that affected the change of ecological footprint by the Stochastic Impacts by Regression on Population,Affluence,and Technology (STIRPAT) model.The results showed that increasing trends of regional ecological footprint during 1998-2008 (1.70-2.53 ha/cap) were accompanied by decreasing ecological capacity (0.31-0.25 ha/cap) but expanding ecological deficit (1.39-2.28 ha/cap).The distribution pattern of ecological footprint and the degree of sustainable development varied distinctly from city to city in YDR.In 2008,the highest values of ecological footprint (3.85 ha/cap) and the lowest one of sustainable development index (SDI=1) in YDR were both presented in Shanghai.GDP per capita (A) was the most dominant driving force of EF and the classical EKC hypothesis did not exist between A and EF in 1998-2008.Consequently,increasing in ecological supply and reducing in human demand due to technological advances or other factors were one of the most effective ways to promote sustainable development in YDR.Moreover,importance should be attached to change our definition and measurement of prosperity and success. 相似文献
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Duan Lin XiuQin LiHongDa Fang YanHong DongZhuoXuan Huang JiaHui Chen 《Estuarine, Coastal and Shelf Science》2011
To study the relationships between species distribution and environmental variables, calanoid copepods were classified and enumerated, and environmental variables were analyzed along 91 sites of the Pearl River Estuary (China) and adjacent waters. The 91 sites were divided into 3 groups based on surface salinity: the Inner area had salinity level below 10‰ and was mostly located in the Pearl River Estuary, the Coastal area had salinity between 10‰ and 32‰ and was almost located along the coastline, while the Offshore area had salinity level higher than 32‰ and was mainly located in the open area. Indicator Species Analysis was conducted to identify the indicator species within each group from among all calanoid copepods taxa. We found that the Inner area was characterized by Acartiella sinensis, Pseudodiaptomus poplesia and Pseudodiaptomus inopinus, the coastal area was characterized by Temora turbinata and Subeucalanus subcrassus, and the Offshore area was characterized by Paracandacia truncata, Subeucalanus subtenuis, Euchaeta rimana, Pareucalanus attenuatus, Rhincalanus cornutus, Cosmocalanus darwini, Centropages gracilis, Undinula vulgaris, Nannocalanus minor and Paraeuchaeta russelli. Canonical Correspondence Analysis (CCA) was used to identify relevant biotic and abiotic parameters that can best explain the distribution of calanoid copepods. CCA showed that during the summer of 2006, salinity, nutrient variables, especially SiO3–Si, NO3–N and DTN, Depth and Chl a were the environmental variables that strongly impacted the distribution and community structure of calanoid copepods. 相似文献
638.
广州番禺东涌剖面样品的AMS(磁谱仪)年龄及红树林孢粉分析结果表明,珠江三角洲存在晚更新世和全新世的红树林,红树林是海侵的标志之一.按照检出红树属花粉的9个剖面的分布以及5处埋藏红树林腐木的分布,可以描绘出全新世海侵的边界.根据东涌剖面的沉积旋回、样品年龄、红树林花粉含量曲线、半咸水-淡水硅藻及热性-温性硅藻含量曲线的综合分析,可将沉积环境的变迁分为4个阶段.第一阶段和第三阶段的海侵有利于红树林的发展,第二阶段不利于红树林的发展,第四阶段的晚全新世,红树林的生长频繁,显示人为因素的影响. 相似文献
639.
不同流路时期黄河三角洲沿岸余流场的数值对比研究 总被引:1,自引:0,他引:1
黄河入海流路改道变迁频繁,有关不同流路时期沿岸余流场变化的认识将为理解入海泥沙输送特征的变动和沿岸泥沙动态提供重要的水动力基础,通过数值对比实验,以分处黄河三角洲北、东两岸的钓口和清水沟流路为例,对比研究了两个流路基本稳定后的初期黄河三角洲沿岸余流场结构及其流速的变化.结果表明,虽然两个不同流路时期沿岸流系的总体趋势存在一致性,但不同岸段的局部余流场结构、流速及其分布在不同季节都发生了程度不一的变化.在流场结构上,夏、冬季的差异很小,而春、秋季的差异相对较大,特别是在10m以浅的近岸海域的变化明显.高流速区分布,在钓口流路时期具有随各突出沙嘴而生的特点,清水沟流路时则是沿岸线走向、呈条带状延伸,且其分布范围更大、中心流速更高.沿岸余流流速在清水沟流路时期比钓口流路时期大很多,以清水沟口以南海域的流速增加最显著,北岸海域其次,清水沟口以北、神仙沟以南岸段的变化最小,在季节上以冬季增幅最明显.两个不同流路时期沿岸潮致余流场的总体特征也是基本一致的,分布于甜水沟沙嘴(清水沟口)南、北部的涡环结构在清水沟流路时期明显向东北方向移动,清水沟流路时期神仙沟和甜水沟等原沙嘴附近的潮致余流流速存在明显的减小. 相似文献
640.