地缘政治环境中的情景分析：中国的视角     

熊琛然  王礼茂  屈秋实  方叶兵  向宁 《世界地理研究》2019,28(3):1-10

地缘政治环境具有不确定性,难以用简约化理论和量化手段来应对,故尝试运用情景分析法来阐释其在地缘政治环境中的适用性。情景分析法是一种对未来可能出现的多种状况进行描述的方法,具有应对地缘政治环境的不确定性和弥补简约化理论解释和预测能力不足的功能。基于地缘政治想象,地缘政治行为主体进行的地缘政治实践改变了既有地缘政治状态的结果,从而引起地缘政治环境的变化。以此为背景将情景分析法应用于分析中国周边地缘政治环境,预测可能会出现中美竞合、中美俄日印五强博弈、部分周边国家游离于大国间、朝越菲等弱国逞强等四种常规情景和领土争端引发领土战争、美国军事手段消除朝鲜核威慑、朝鲜半岛冲突引发大国对抗等三种突发情景以及“一带一路”倡议下的周边命运共同体情景。  相似文献   

山东地区近期垂直形变场精细特征分析     

杜存鹏  殷海涛  曲国庆  孙振 《大地测量与地球动力学》2019,39(2):117-121

利用山东地区38个GNSS基准站2011～2016年连续6a的观测数据,对山东地区地壳垂向形变场特征进行系统分析。结果表明,山东地区地壳垂向形变具有明显的差异性,形变量最大的区域为山东西南部地区,形变速率约为-24.0mm/a;西北部地区形变速率较大,为-15.0mm/a;东南部以及沿海地区沉降速率较小,为-0.5～3.0mm/a;而在中部地区(泰山山脉)呈隆升趋势,形变速率为0.3～5.0mm/a。  相似文献   

Spatio-temporal evolution of ecologically-sustainable land use in China's Loess Plateau and detection of its influencing factors     

QU Lu-lu  LIU Yan-sui  CHEN Zong-feng 《山地科学学报》2019,(5)

Ecological land(Eco-land) is a basic resource for human beings to survive, and eco-land use is a strategy, a way to manage the land resource. So, ecologically-sustainable land use is essential for human beings to survive. This paper investigates the spatiotemporal characteristics and mechanisms of urban-rural eco-land using a new and innovative integration way based on eco-land change data in China's Loess Plateau(LP) prefecture level cities and explores factors of eco-land change. The spatial difference characteristic of eco-land among different level cities in the LP is that: small cities big cities middle cities. From 2009 to 2016, the eco-land in the LP from the perspective of urban-rural areas has changed significantly. Significant differences of urban-rural eco-land were identified among various urban growth types, and all the cities in the LP were further classified into four types based on eco-land change trend, with type A and B cities identified as the vital zone and major zone. Taking the eco-fragile region Loess Plateau(LP) as an example, our results demonstrated that the migrants to cities in LP could relieve ecological pressures and promote restoration of ecological vegetation. We have demonstrated that urbanization and the influence of government policy can be discerned through the quantification of the spatial-temporal change of eco-land and suggest that combining both urban and rural eco-land can support more effective land use decisions and provide theoretical basis for the practical application of urban planning, policy-making and sustainable development. What's more, governments should strive to population mobility and restore vegetation to sustain this fragile ecological environment.  相似文献   

贻贝附着基海带苗种运输技术探究     

吕继发  杜欣欣  曲学伟  刘升平 《海洋科学》2019,43(6):88-94

中介生物辅助大型海藻海底基质附着技术,是采用海面撒播苗种方法,进行大型海藻海底增殖的核心技术。研究发现,该贝、藻复合体苗种的运输比普通水产苗种运输难度显著增加。本文采取传统的干运、水运以及发明的淋水运输3种不同方式,进行了贻贝附着基海带苗种运输技术研究。结果表明:干运3h内苗种的存活率和生长速度与对照组差异不显著(P0.05);水运1h以上苗种的存活率与对照组差异显著(P0.05);淋水运输24 h内苗种的存活率和生长速度与对照组差异不显著(P0.05)。实验说明:水运不适合该苗种运输;在露空时间3 h以内,干运是最经济、最便捷的苗种运输方法;在露空24 h以内,采取淋水运输能够保证苗种的成活率,可以作为该苗种常规的运输方法。  相似文献   

威海市天鹅湖海洋牧场底层海水溶解氧浓度时间变化特征   总被引：2，自引：2，他引：0  

刘禹铖  刘子洲  顾艳镇  李培良  孙利元  翟方国  宋洪芳  李子牛  王兆宇  贾乃东  曲俐儒  盖芸芸 《海洋科学》2019,43(9):41-53

依据威海市天鹅湖海洋牧场2016年7—10月海洋生态环境海底有缆在线观测系统的长期连续观测数据,研究了该牧场底层海水溶解氧浓度的时间变化特征,并探讨了其可能的影响因素。结果表明:观测期间海水溶解氧浓度平均值为6.65mg/L,呈先下降后上升的变化趋势,月平均值最小为6.36mg/L,出现在9月。溶解氧月浓度标准差呈先减小后增大的变化趋势,而溶解氧日浓度标准差总体变化趋势与月浓度标准差相反。底层海水基本上处于不饱和状态,月均溶解氧消耗量在观测期间逐月增大。海水温度是影响溶解氧浓度变化的主要因素。7月1日至8月24日期间,牧场海域存在季节性温跃层。7月1日至17日与8月11日至24日期间,溶解氧浓度下降可能受季节性温跃层和海水温度上升的共同影响;7月18日至8月1日期间,溶解氧浓度变化不受季节性温跃层控制。大风过程会增强表、底层海水交换,使溶解氧浓度上升。月均溶解氧浓度日变化均表现出双峰双谷的特征,与月均水深日变化对比, 7—8月0—13时无显著正相关性, 7—8月1—23时及9—10月相位变化基本一致,涨潮时海水溶解氧浓度升高,而落潮时降低,说明研究区域外海水溶解氧浓度很可能高于近岸,而潮流输运过程使得近岸海水溶解氧浓度随潮汐过程变化。  相似文献   

加强海洋科技创新支撑山东海洋强省建设的战略研究     

姜勇  党安涛  胡建廷  王继业  曲茜  罗志全  王娴  孙高祚 《海洋开发与管理》2019,36(9):38-42

山东加快发展海洋经济、建设海洋强省,是深入贯彻落实习近平总书记经略海洋、建设海洋强国重要指示精神的重要举措,是山东实现两个走在前列、推进新时代现代化强省建设的必由之路。海洋是现代科技的"新战场",建设海洋强省,海洋科技创新是核心关键,也是重要保障。山东海洋科技力量优势明显,但也存在着一些问题和不足,打造山东半岛海洋科技创新中心,提升海洋科技创新能力,完善区域海洋科技创新体系,对于推动海洋经济发展,支撑引领山东新时代海洋强省建设具有重要意义。  相似文献   

Bacterial communities fluctuate in abundance and diversity under simulated oil-contaminated seawater conditions     

LI Xiaohong  YOU Cai  QU Liang  ZHOU Bin  TANG Xuexi  XIAO Hui 《海洋湖沼学报（英文）》2019,(2):615-627

Marine bacteria have recently been identified as a potent solution for petroleum hydrocarbon degradation in response to hazardous oceanic oil spills. In this study, a mesocosm experiment simulating a petroleum spill event was performed to investigate changes in the abundance, structure, and productivity of bacterial communities in response to oil pollution. Cultured heterotrophic bacteria and total bacteria showed a consistent trend involving an immediate decrease in abundance, followed by a slight increase, and a steady low-level thereafter. However, the changing trend of bacterial productivity based on bacterial biomass and bacterial volume showed the opposite trend. In addition, the density of oil-degrading bacteria increased initially, then subsequently declined. The change in the bacterial community structure at day 0 and day 28 were also analyzed by amplified ribosomal DNA restriction analysis (ARDRA), which indicated that the species diversity of the bacterial community changed greatly after oil pollution. Alphaproteobacteria (40.98%) replaced Epsilonproteobacteria (51.10%) as the most abundant class, and Gammaproteobacteria (38.80%) became the second most dominant class in the whole bacterial community. The bacterial communities in oil-contaminated seawater (32 genera) became much more complex than those found in the natural seawater sample (16 genera). The proportion of petroleum-degrading bacteria in the oil-contaminated seawater also increased. In this study, culture-dependent and culture-independent approaches were combined to elucidate changes in both bacterial productivity and community structure. These findings will contribute to a better understanding of the role that bacteria play in material cycling and degradation in response to oil pollution.  相似文献   

中甸弧碰撞造山作用和岩浆成矿系统   总被引：64，自引：1，他引：64  

杨岳清  侯增谦  黄典豪  曲晓明 《地球学报》2002,23(1):17-24

中甸弧位于西南三江构造火成岩带义敦岛弧的南端，它的演化经历了洋壳俯冲（210－235Ma）、陆陆碰撞（80－88Ma）和陆内汇聚（28Ma）三大造山作用。在俯冲造山作用中产生了浅成－超浅成斑、玢岩，并发育了与之有关的斑岩型、夕卡岩型、浅成低温热液脉型铜多金属矿床。在碰撞造山作用中形成了与后造山黑云母花岗岩和与之有关的蚀变花岗岩型、石英脉型钨－钼矿床。在陆内汇聚造山作用中产生了深源正长岩类和与之有关的斑岩型金矿。火成岩类型和成矿作用的多样化表明，在中甸弧中具有广阔的找矿前景。  相似文献   

福建马坑铁矿床形成温度和压力实验的初步研究   总被引：7，自引：0，他引：7  

梁祥济  曲国林 《地球学报》1982,4(1):83-94

<正> 马坑铁矿赋存于石炭—二叠纪合火山岩的碳酸盐岩—碎屑岩建造的地层中,由辉绿岩和大理岩在火山气热液作用下形成含矽卡岩矿物组合的磁铁矿床。这类铁矿分布较广,是一个重要的矿床类型。为了探索这类矿床形成的温度、压力和介质环境,我们继《福建马坑矽卡岩分带的模拟实验》之后,采用马坑天然辉绿岩和大理岩作为试料,对该矿床形成的温度和压力进行了初步的实验研究。  相似文献   

伪随机脉冲参数对BDS卫星定轨精度的影响分析     

张睿  涂锐  卢晓春  黄观文  王乐  瞿伟 《大地测量与地球动力学》2018,38(3):282-286

采用附加伪随机脉冲参数的动力学定轨方法对BDS卫星进行定轨,分别给出不同时间间隔的伪随机脉冲参数估计方案对BDS卫星常规状态、姿态转换状态以及进入地影状态时定轨精度的影响。结果表明,常规状态下,伪随机脉冲参数对GEO卫星定轨精度改善显著,相对较优的伪随机脉冲参数估计间隔与各类卫星运行周期吻合;对于姿态转换状态以及进入地影状态,6 h的伪随机脉冲参数估计间隔有助于提高相应卫星的定轨精度。  相似文献