“一带一路”沿线国家2020—2060年人口经济发展情景预测   总被引：1，自引：0，他引：1  

姜彤  王艳君  袁佳双  陈迎  高翔  景丞  王国复  吴先华  赵成义 《气候变化研究进展》2018,14(2):155-164

本文应用IPCC共享社会经济路径(SSPs),开展“一带一路”沿线国家的人口和经济情景预测,研究可持续路径(SSP1)、中间路径(SSP2)、区域竞争路径(SSP3)、不均衡路径(SSP4)和化石燃料为主发展路径(SSP5)下,“一带一路”沿线国家社会经济的变化趋势,构建“一带一路”沿线国家人口和经济发展情景数据库,服务于气候变化影响、风险、适应和减缓路径方案设计。研究表明：(1)2016年“一带一路”沿线国家总人口占全球人口的62.3%,GDP总量占全球的31.2%。其中“21世纪海上丝绸之路”经过的东南亚和南亚地区经济总量大,但人口密集,人均GDP较低;“丝绸之路经济带”涵盖的中亚、西亚、东欧等地区人口密度小,经济相对发达。(2)“一带一路”沿线国家未来人口和经济整体呈增长趋势,但不同的社会经济发展政策对人口经济变化有重大影响。不同的SSPs路径下,2060年人口将比2016年水平增加3.3亿(SSP5)~18.3亿(SSP3),经济总量达到2016年水平的3.0（SSP3)~6.4倍(SSP5)。人口占全球总量的比重持续减少,经济比重则有所增加。(3)21世纪中期(2051—2060年),“一带一路”沿线国家平均人口密度约95人/km²,GDP约164万美元/km²。不同社会经济发展政策间人口经济分布有一定差异,SSP3路径下大部分国家人口增长迅速,但经济发展缓慢,人均GDP多低于2万美元;SSP5路径下人口相对较少,经济发展迅速,大多数国家人均GDP超过2.5万美元;其他3种路径下人口经济发展介于SSP3和SSP5之间。  相似文献   

Teleconnection between Sea Ice in the Barents Sea in June and the Silk Road,Pacific–Japan and East Asian Rainfall Patterns in August   总被引：3，自引：0，他引：3  

Shengping HE  Yongqi GAO  Tore FUREVIK  Huijun WANG  Fei LI 《大气科学进展》2018,35(1):52-64

In contrast to previous studies that have tended to focus on the influence of the total Arctic sea-ice cover on the East Asian summer tripole rainfall pattern, the present study identifies the Barents Sea as the key region where the June sea-ice variability exerts the most significant impacts on the East Asian August tripole rainfall pattern, and explores the teleconnection mechanisms involved. The results reveal that a reduction in June sea ice excites anomalous upward air motion due to strong near-surface thermal forcing, which further triggers a meridional overturning wave-like pattern extending to midlatitudes.Anomalous downward motion therefore forms over the Caspian Sea, which in turn induces zonally oriented overturning circulation along the subtropical jet stream, exhibiting the east–west Rossby wave train known as the Silk Road pattern. It is suggested that the Bonin high, a subtropical anticyclone predominant near South Korea, shows a significant anomaly due to the eastward extension of the Silk Road pattern to East Asia. As a possible descending branch of the Hadley cell, the Bonin high anomaly ultimately triggers a meridional overturning, establishing the Pacific–Japan pattern. This in turn induces an anomalous anticyclone and cyclone pair over East Asia, and a tripole vertical convection anomaly meridionally oriented over East Asia. Consequently, a tripole rainfall anomaly pattern is observed over East Asia. Results from numerical experiments using version 5 of the Community Atmosphere Model support the interpretation of this chain of events.  相似文献   

Asymmetric Relationship between the Meridional Displacement of the Asian Westerly Jet and the Silk Road Pattern     

Xiaowei HONG  Riyu LU  Shuanglin LI 《大气科学进展》2018,35(4):389-397

In previous work, a significant relationship was identified between the meridional displacement of the Asian westerly jet(JMD) and the Silk Road Pattern(SRP) in summer. The present study reveals that this relationship is robust in northward JMD years but absent in southward JMD years. In other words, the amplitude of the SRP increases with northward displacement of the jet but shows little change with southward displacement. Further analysis indicates that, in northward JMD years, the Rossby wave source(RWS) anomalies, which are primarily contributed by the planetary vortex stretching, are significantly stronger around the entrance of the Asian jet, i.e., the Mediterranean Sea–Caspian Sea area, with the spatial distribution being consistent with that related to the SRP. By contrast, in southward JMD years, the RWS anomalies are much weaker.Therefore, this study suggests that the RWS plays a crucial role in inducing the asymmetry of the JMD–SRP relationship.The results imply that climate anomalies may be stronger in strongly northward-displaced JMD years due to the concurrence of the JMD and SRP, and thus more attention should be paid to these years.  相似文献   

三江源区毒杂草型退化草地植被光谱特征分析     

周伟  李浩然  石佩琪  谢利娟  杨晗 《地球信息科学学报》2020,22(8):1735-1742

毒草型退化草地具有群落演替特点,通过高光谱遥感技术反演毒杂草分布与退化草地群落结构能对该类退化草地进行有效监测,而光谱特征分析是毒杂草与优良牧草遥感识别的基础。本文选取了三江源区毒草型退化草地的8种典型毒杂草和4种优良牧草的地面实测高光谱数据作为研究样本,经过SG平滑、包络线去除、导数变换和光谱参量化对毒杂草种和优良牧草种的光谱特征进行了分析,并通过马氏距离法提取其特征识别波段。结果表明：① 8种典型毒杂草和4种优良牧草的 “近红外峰值”差异较大,其中鹅绒萎陵菜的“近红外峰值”达到60.07%,而最小者早熟禾仅为17.53%;② 经包络线去除处理后,植被光谱曲线中吸收谷和反射峰光谱差异更加明显,且可减少环境背景对植被光谱的影响,如沼泽草甸的鹅绒委陵菜和驴蹄草,其“绿峰幅值”分别为6.46%和6.89%,经处理后其“绿峰指数”分别为0.2866和0.3671,而在2种环境下生长的同一草种（狼毒草1和狼毒草2）的峰谷特征差异不明显;③ 基于马氏距离法提取的毒杂草与优良牧草的敏感识别波段主要分布在680~750 nm和900~1000 nm波长范围内,以醉马草与矮嵩草为例,其基于反射率的敏感识别波段为713.1~737.1 nm和934.6~965.6 nm。该研究可为利用高光谱遥感进行大面积毒杂草草种识别和植被群落生长监测提供重要科学依据,对于三江源区毒杂草的监测防治和畜牧业的可持续发展具有重要意义。  相似文献   

斯里兰卡近海海洋生态环境变化遥感监测分析     

叶虎平  廖小罕  何贤强  岳焕印 《地球信息科学学报》2020,22(7):1463-1475

斯里兰卡是海上丝绸之路沿线重要的节点国家,其周边海域生态环境变化与经济发展、休闲生活和食品安全密切相关。利用2002—2017年的MODIS遥感反演产品对斯里兰卡岛周边海域、关键节点港口科伦坡的生态环境参数年际变化规律分别进行分析和2003—2012年的MERIS遥感反射率产品对保克海峡进行水体类型时空分析,结论如下：① 研究区内光合作用有效辐射高值出现在马纳尔湾,海域沿岸浮游植物生物量相对较高,与海表温度负相关,外海浮游植物生物量极低,与透明度负相关。② 科伦坡港附近水温（海表温度）、海面光照强度（光合作用有效辐射）、水体清洁度（海水透明度）、海洋食物网基础的浮游植物生物量（叶绿素浓度）和浮游植物净初级生产力最大值分别出现在4月、3月、3月、8月、7月,致灾因素重点关注8月潜在的赤潮。③ 保克海峡浑浊带的源头是印度的卡里梅尔角,由高韦里河携带大量泥沙造成。这有助于了解和认识高时空变化的保克海峡及斯里兰卡周边海域在不同时间-空间的海洋生态环境。  相似文献   

道路拨地的作业方法   总被引：1，自引：1，他引：0  

李晓艳 《北京测绘》2008,(4)

主要讲述道路拨地在确定范围线时,为了解决矛盾所进行的三次修改,以及对在成果图中测绘范畴内不可解决的矛盾给与显示,以提示用地单位认真对待这些作业过程。  相似文献   

世界遗产预备项目“丝绸之路-海路-中国段”研究   总被引：2，自引：1，他引：1  

阙维民 《地理科学》2017,37(11):1678-1688

中国海上丝绸之路申遗于2016年正式启动,迄今尚无有关中国海上丝绸之路申遗专题的综合研究成果。首先建议申遗项目的中英文名称：丝绸之路-海路-中国段（Silk Road-Maritime Route in China）,然后探讨“丝绸之路”申遗的国际背景（除1项“丝绸之路：长安-天山廊道路网”系列跨国世界遗产外,另有8国递交9项“丝绸之路”预备项目）与“丝绸之路-海路-中国”项目的申报意义（主动性、创新性、唯一性、均衡性、政治性、世界性）。并就申报项目的遗产内容提出具体建议：遗产地从31处扩展至141处,遗产类型在文物遗产的基础上增加了聚落遗产（历史文化名镇、名村、街区）。最后提出在UNESCO世界遗产委员会建立“丝绸之路-海路”申遗专项基金。  相似文献   

“Ghost cities” identification using multi-source remote sensing datasets: A case study in Yangtze River Delta     

《Applied geography (Sevenoaks, England)》2017

Drastic urbanization has taken place in China during the last two decades. Recently, a considerable number of “ghost cities” have emerged due to the extensive and unreasonable urban expansion which far exceeds the practical demand. In order to investigate “ghost cities”, we proposed a feasible framework by utilizing multi-source remote sensing datasets, including nighttime light imagery, land cover type products and population grid. After eliminating blooming effect of nighttime imagery by a proposed modified optimal threshold method (MOTM) and extracting built-up area from land cover type products, we developed a “ghost city” index (GCI) to quantify and evaluate the intensity of “ghost city” phenomenon in Yangtze River Delta at county/district level. The GCI was established according to the intrinsic features of “ghost cities”, comprising three criteria: consistency of lit area and built-up area, illumination intensity and population density. Then, we explored the spatial pattern of “ghost cities” of different GCI categories and the ternary contour was applied to demonstrate the key factor among three criteria. Our finding implies that “ghost cities” are prominently spatial clustered. Meanwhile, counties and new development zones have higher risk of suffering from the phenomenon, while capital cities and municipal cities have an alleviative effect for ambient regions. Besides, regions with higher intensity of the phenomenon tend to have less balanced composition among three criteria. Our results show good consistency with previous reports and studies, providing a more objective and spatial explicit insight into the “ghost city” phenomenon. Our findings do not only prove the capability of monitoring “ghost cities” using remote sensing data, but would also be beneficial to urban planning and regional sustainable development.  相似文献   

丝绸之路经济带沿线省份科技创新效率及其影响因素     

程广斌  张雅琴 《地域研究与开发》2017,36(2)

将科技创新分解为技术研发和成果转化2个阶段,运用SUPER-SBM模型对丝绸之路经济带沿线省份科技创新效率进行综合评价,并选用面板Tobit模型对技术研发效率和成果转化效率影响因素进行分析。结果表明:总体上,丝绸之路经济带沿线各省份科技创新效率不断提升,但不同省份之间在科技创新的不同阶段效率差距较大。劳动者素质对技术研发效率的提高有显著正向影响,对成果转化效率影响不显著;对外开放对技术研发效率有显著正向影响,而对成果转化效率有显著负向影响;政府支持对技术研发效率影响不显著,对成果转化效率有显著正向影响;产业结构、基础设施对技术研发效率和成果转化效率影响均不显著。  相似文献   

Valorization of harbor dredged sediment activated with blast furnace slag in road layers     

Abdelwaheb Ben Slama  Nesma Feki  Daniel Levacher  Moncef Zairi 《国际泥沙研究》2021,36(1):127-135

The valorization solutions for dredged sediment have been the subject of a great number of investigations over the previous decades.In the current present study,treatment of polluted dredged sediment fom the commercial port of Sfax,Tunisia,is proposed.An industrial byproduct(blast furnace slag)was used to bind raw sediment for a reuse in road engineering.Following standards of this field,the raw sediment first was identified and classified according to the French technical guidance.Then an environmental assessment was applied due to the presence of heavy metals.The concentrations were measured on the raw sediment particles so as to control the binding effect on heavy metals.Sediment mixtures consisted of a mix of sand and a blast furnace slag activated with quicklime.Different mixtures were tested and some were proposed for sub-layer applications.The Sfax commercial port raw sediment is considered as a sandy loam with a very low fraction of clay.The measured concentrations of heavy metals exceed the recommended thresholds for cadmium,copper,lead,and zinc.These can induce hazardous effects in the case of their dumping into the sea.On the other hand,the concentrations of the detected elements after leaching tests run on raw sediment samples are very low compared to the thresholds;such results highlight a possible recycling of the raw sediment in subgrade layers without any negative impact.Suitable formulations were deduced for road engineering tests relying on the ratio the California Bearing Ratio index and the immediate bearing index.If the obtained ratio exceeds one,the treated sediment can be recycled and used in road layers.  相似文献