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101.
为推动我国振兴东北老工业基地战略,充分发挥我国东北地区面向海洋的区位优势,加快区域经济的发展和繁荣,文章从基础条件、空间布局和实施重点3个方面,分析我国东北地区海洋经济的区域协同发展战略。研究结果表明:辽宁省是海洋经济大省,而在打破传统"沿海"观念的基础上发展吉林省和黑龙江省的毗海经济和向海经济,有利于辽宁省海洋产业的转型升级和整个东北地区海洋经济的区域协同发展,俄罗斯远东发展战略与我国振兴东北老工业基地战略也为此创造了环境和机遇;我国东北地区海洋经济区域协同发展的空间布局为"一轴一带两区",其中"一轴"为大连至佳木斯的铁路通道,"一带"和"两区"分别为辽宁沿海经济带、延边州海洋经济区和绥芬河海洋经济区,各地发挥各自的区位和产业优势,科学布局海洋产业,形成集聚、辐射和带动力量;我国东北地区应大力推动海洋经济一体化、资源配置市场化、对外开放国际化和科学技术创新化,从而实现海洋经济的区域协同发展。  相似文献   
102.
Ren  Yufei  Fang  Chuangling  Lin  Xueqin  Sun  Siao  Li  Guangdong  Fan  Beili 《地理学报(英文版)》2019,29(8):1315-1330

Urban agglomerations in China have become the strategic core of national economic development and the main component of the new type of urbanization. However, they are threatened by a series of eco-environmental problems and challenges, including the severe overexploitation of natural resources. Eco-efficiency, which is defined as accomplishing the greatest possible economic benefit with the least possible resource input and damage to the environment, is used as an indicator to quantify the sustainability of urban agglomerations. In this work, a traditional data envelopment analysis (DEA) model with a slack-based measurement (SBM) model of undesirable outputs, was used to assess and compare the economic efficiency and eco-efficiency of four major urban agglomerations in eastern China (UAECs) in 2005, 2011, and 2014. The spatio-temporal characteristics of the evolution of urban agglomerations were analyzed. Based on the results of a slack analysis, suggestions for improving the eco-efficiency of the four UAECs are provided. The overall economic efficiency of urban agglomerations located in the Shandong Peninsula, Yangtze River Delta, and Pearl River Delta displayed a V-shaped pattern (decreased and then increased). In contrast, the overall economic efficiency of the Beijing-Tianjin-Hebei urban agglomeration declined during the study period. The Beijing-Tianjin-Hebei urban agglomeration had a considerable loss of economic efficiency due to pollution, whereas the Shandong Peninsula urban agglomeration was less impacted. Overall, the eco-environmental efficiency of the four UAECs declined from 2005 to 2011 and then increased from 2011 to 2014. In addition, the urban eco-efficiency in the four coastal UAECs was characterized by different evolution patterns. The eco-efficiency was higher in the peri-urban areas of the core cities, riverside areas, and seaside areas and lower in the inland cities. The core cities of the Beijing-Tianjin-Hebei, Yangtze River Delta, and Pearl River Delta urban agglomerations were characterized by high resource consumption, economic benefit output, and eco-efficiency. In most of cities in the urban agglomerations, the emission of pollutants declined, leading to a reduction of pollutants and mitigation of environmental problems. In addition, a differential analysis, from the perspective of urban agglomeration, was performed, and concrete suggestions for improvement are proposed.

  相似文献   
103.
大兴安岭西侧满洲里—新巴尔虎右旗地区广泛分布的满克头鄂博组缺乏古生物化石和年代学方面的系统研究,因此地层形成时代上存在争议,形成的古气候环境不明。本次在野外地质调查中,在满克头鄂博组发现了Nestoria(尼斯托叶肢介)化石和Cedripites-Piceaepollenites-Psophosphaera孢粉组合,其形成时代为晚侏罗世晚期,也指示了其形成的古气候环境为亚热带、半湿润-湿润气候。在该组中上部流纹岩中获得锆石LA-ICP-MS U-Pb年龄为156.61±0.96Ma,结合古生物化石年代学特征,确定满克头鄂博组形成于晚侏罗世中晚期;同时,满克头鄂博组中流纹岩的锆石U-Pb年龄(156.61±0.96Ma)指示以Nestoria为代表的叶肢介化石带时限为启莫里阶。  相似文献   
104.
城镇化与生态环境近远程耦合关系研究进展   总被引:5,自引:1,他引:4  
城镇化与生态环境近远程耦合关系研究是国际人地系统研究的前沿和热点领域,对于如何协调中国城镇化与生态环境的关系问题也具有重要的参考价值。本文紧扣城镇化与生态环境近远程耦合关系研究主题,在对国际研究进行梳理的基础上,集中从城镇化与生态环境近远程耦合关系理论、方法以及关键应用领域三个方面,对城镇化与生态环境近远程耦合关系研究国际前沿与进展进行评述。分析发现,国际上近远程耦合概念提出时间不长,其理论的完备性与系统性尚显薄弱,对实证研究统领性指导还略显不足。而从其他研究视角出发,国际上对互为远端的人地系统间关联现象进行了大量研究,实证内容充足,内涵丰富。展望未来,关注城市群地区城镇化与生态环境近远程耦合关系、挖掘城镇化与生态环境近远程耦合主导路径与动态演变特征、加强中国城镇化与生态环境近远程耦合理论研究,是推动中国城镇化与生态环境耦合研究迈向新的发展阶段的重要方向。  相似文献   
105.
石准立  谢广东 《现代地质》1998,12(4):477-484
摘  要  着重研究了东伙房金矿床矿物包裹体的空间分布, 并将其用于解释矿床成因。 研究 了成矿压力场、 温度场和热液沸腾与矿质沉淀的关系, 利用矿物包裹体气相和液相成分测定 结果讨论了金的搬运形式。 论述了碱性潜火山岩正长斑岩体与成矿的关系, 指出矿床形成于 印支期地幔热柱引发的张性成矿动力学背景之下, 矿床属于和碱性岩有关的中浅成高中温热 液矿床。  相似文献   
106.
By using the methods of qualitative and quantitative analysis, the species composition and dominant genus of harmful, ciliates in young abalone culture ponds are studied. Totally 68 species of ciliates, belonging to 3 classes, 16 orders and 46 genus, are found. The dominant ciliate species are Aspidisca leptaspis, Vorticella sp. and Euplotes rariseta. During the young abalone cultivation, the numbers of young abalones increase first,and then show a trend of decreasing. The relationship between the density and composition of ciliates and the density of algae in the young abalone culture ponds is also discussed.  相似文献   
107.
The Ningqiang meteorite is a fall carbonaceous chondrite, containing various Ca-, Al-rich inclusions that usually escaped from secondary events such as high-temperature heating and low- temperature alteration. However, it has not yet been classified into any known chemical group. In order to address this issue, 41 elements of the bulk Ningqiang meteorite were analyzed using inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma atom emission spectrometry (ICP-AES) in this study. The Allende (CV3) carbonaceous chondrite and the Jilin (H5) ordinary chondrite were also measured as references, and our analyses are consistent with the previous results. Rare earth and other refractory lithophile elements are depleted in Ningqiang relative to both Allende and mean CK chondrites. In addition, the REE pattern of Ningqiang is nearly flat, while that of Allende shows slight enrichment of LREE relative to HREE. Siderophile elements of Ningqiang are close to those of mean CK chondrites, but lower than those of Allende. Our new analyses indicate that Ningqiang cannot be classified into any known group of carbonaceous chondrites, consistent with previous reports.  相似文献   
108.
The Qom Formation comprises Oligo-Miocene deposits from a marine succession distributed in the Central Basin of Iran. It is composed of five members designated as A-F. Little previous work exists on the sequence stratigraphy. Based on an integrated study of sequence stratigraphy with outcrop data, wells and regional seismic profiles, the Qom Formation is interpreted as a carbonate succession deposited in a mid-Tertiary back-arc basin. There are two second-order sequences (designated as SS1 and SS2) and five third-order sequences (designated as S1-S5). Five distinct systems tracts including transgressive, highstand, forced regressive, slope margin and lowstand have been recognized. The relationship between the sequences and lithologic sub-units has been collated and defined (S1 to S5 individually corresponding to A-C1, C2-C4, D-E, the lower and upper portions of F); a relative sea level change curve and the sequence stratigraphic framework have been established and described in detail. The coincidence of relative sea level change between that of the determined back-arc basin and the world indicates that the sedimentary cycles of the Qom Formation are mainly controlled by eustatic cycles. The variable combination of the systems tracts and special tectonic-depositional setting causally underpin multiple sequence stratigraphic framework styles seen in the carbonates of the back-arc basin revealing: (1) a continental margin basin that developed some form of barrier, characterized by the development of multiple cycles of carbonate-evaporites; (2) a flat carbonate ramp, which occurred on the southern shelf formed by the lack of clastic supply from nearby magmatic islands plus mixed siliciclastics and carbonates that occurred on the northern shelf due to a sufficient clastics supply from the land; and (3) a forced regressive stratigraphic stacking pattern that occured on the southern shelf and in basin lows due to the uplifting of the southern shelf. Thick and widespread aggradational framework limestone usually occurs in the initial sequences (S1 and S3) of the supersequence, which led to preferential oil reservoir deposition but a lack of source and cap rocks, whereas the retrogradational and progradational framework limestone usually occurs in the later sequences (S2 and S4-S5) of the supersequence, which results in two perfect sets of source, reservoir and cap rock assemblies, so that the limestone in sub-member C2-C4 and the F-Member can be predicted as important objects for oil exploration.  相似文献   
109.
珠江三角洲及其邻近海域第四纪地质与地震危险性   总被引:6,自引:2,他引:4  
陈伟光 《华南地震》1998,18(2):58-62
从第四纪地质研究的角度分析了珠江三角洲地区的地震危险性,认为北东,近东西和北西向三组断裂带把整个珠江三角洲断陷分割成7个次一级断块,并根据控制各次级断块的断裂第四纪活动性的强弱。  相似文献   
110.
香港地区地震危险性分析   总被引:1,自引:0,他引:1  
在前人研究的基础上,对香港地区的潜在震源区及有关地震活动性参数作了研究和调整。对不同学者给出的衰减关系作了对比和分析,并将计算结果与近年不同学者在邻近地区的工作成果作了比较,最后进行了不确定性分析。结果表明,香港地区50年超越概率10%的基岩水平加速度峰值(PGA)界于75gal和115gal之间,九龙场点为927gal,本区各场点的地震基本烈度为Ⅶ度。  相似文献   
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