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771.
潘竟虎  赖建波 《地理研究》2019,38(7):1678-1693
“腾讯迁徙”大数据基于位置服务,实时、动态、完整、系统地描述了用户日常出行活动的轨迹。通过采集“腾讯迁徙”数据平台中2017年国庆-中秋长假期间国内299个城市之间的逐日人口流动数据,分“出行期、旅途期、返程期”3个时间段,利用复杂网络分析方法,从人口流动集散层级、集散网络体系的分层集聚、人口流动空间格局、网络空间特征等角度分析各时间段城市间的人口流动特征与空间格局。结果表明,腾讯迁徙大数据直观地揭示了国庆-中秋期间中国各地级城市间人口的迁移规律,3个时段人口的净流入均呈现十字形骨架支撑的菱形分布,人流集散中心主要集中在京津冀、长三角、珠三角和成渝四大城市群,与城市等级有较强的一致性。人口流动集散体系呈明显的分层集聚,城市行政级别的高低与人口流动影响力存在一定的正相关关系,大部分城市人口流动处于“相对平衡”状态。人口流动空间格局呈现出明显的核心-边缘结构,大理-鹤岗一线是人口流动强度空间分布的显著分界线,以此线为界,城市网络呈现东密西疏的分布特征和东部并联、西部串联的网络关联特征。人口流动网络总体表现出“小世界”网络特征,局部具有较明显的“社区”结构特征,聚为2个国家级、2个区域级和3个地区级社区。  相似文献   
772.
自国家“十五”规划起,中国现代化综合交通运输体系构建以填空白、补短板、大规模设施建设为主,但近年来人口的增长、流动、空间集聚和生活方式等均发生了新的显著变化。以人为本,科学实施“交通强国”国家战略,亟待开展适应人口发展的现代化综合交通运输体系研究。本文基于国家发展与改革委员会国家“十四五”规划前期重大问题研究的部分成果,从人口与交通系统耦合协同机制出发,在深入分析人口发展及其交通需求趋势的基础上,提出适应人口发展的中国综合交通体系“钻石战略”。以京津冀、长三角、粤港澳、成渝城市群为“钻石”四极,以京沪通道、沪粤通道、粤川通道、京川通道为四边,以长江水陆通道、京港澳通道为十字骨架,以人口流入流出高强度的节点地区为枢纽,并提出构建适应人口发展的现代化综合交通运输体系实施重点,支撑国家重大空间发展战略;实施交通强国、适应人口发展;以人民为中心,打造高品质交通服务。  相似文献   
773.
Earthquake disaster risk,as a typical social disaster risk,is one of the most important risks in modern Chinese society.This study gives definitions of the institution,describes the formation history,the connotations and development and analyzes its role in the control of major social risks caused by earthquakes.Finally,the paper presents recommendations for continuous improvement of this institution under the guidance of risk society theory,and for its application to the government reform and social governance.  相似文献   
774.
朱宝霞  申文庄  马明 《中国地震》2014,30(3):373-381
公众是实现地震重点监视防御区(以下简称地震重防区)防震减灾工作目标、提升社会防震减灾能力的主力军,而公众对地震重防区的认知与防震减灾宣传密不可分.本文通过问卷调查,发现许多公众对地震重防区和相关知识的认知程度低、公众的防震减灾素质有待提高、防震减灾宣传针对地震重防区的内容不够全面、宣传方式和手段不够多样化等问题.据此,提出建议:强化地震重防区宣传,丰富防震减灾宣传内容;防震减灾宣传方式和途径多样化;完善防震减灾宣传教育制度等.  相似文献   
775.
借助数据包络分析方法(DEA)综合测算了国家级风景名胜区旅游效率,结合标准差椭圆和重心坐标探讨了风景名胜区旅游效率重心演化的轨迹与路径,考察了影响演化轨迹的重要因素及其作用机理。结果表明:① 国家级风景名胜区旅游效率总体不高,变化幅度较小,综合效率、纯技术效率及规模效率均呈现明显的波动性特征,说明改革开放初期的风景区旅游发展主要得益于规模投资,有效的货币资本投入是提升旅游发展的主要措施,平均效率值总体表现为下降态势,风景区多数处于无效率状态,DEA最优状态缺乏,导致了风景区生产单元存在一定的资源冗余和开发低效状态。② 从重心的整体分布上看,主要位于107°11'~118°37'E 和29°02'~38°55'N 之间,东西跨度约11°,南北跨度约9°;从旅游效率重心演变的轨迹上来看,综合效率的变化轨迹最大,但总体上都是经历了先西偏南再东偏北再西偏南的历程,其中规模效率和全要素生产率的重心东偏北的趋势相对较小,而综合效率和纯技术效率在重心东偏北的趋势上变化较大。③ 针对风景区旅游效率空间格局动态演化的驱动机制的剖析表明,经济发展水平、资源禀赋、产业结构、交通发展、信息技术及制度供给是影响效率重心偏移的重要因素,促使了效率动态格局的空间演化,优化产业结构,引进先进技术,完善市场引导机制,政府科学调控及资源禀赋改善是促进风景区旅游效率提升的有效路径。  相似文献   
776.
"国家数字地震台网分中心地震波形数据管理和服务"系统   总被引:2,自引:0,他引:2  
国家数字地震台网分中心负责分析处理国家数字地震台网和区域有人值守数字地震台网的资料,为了更好地使这些数据在实际应用中发挥作用,分中心开发研制了一套地震波形数据的管理和服务系统。  相似文献   
777.
In order to investigate the feasibility of reintroducing the South China tiger (Panthera tigris amoyensis) in the Jiangxi Matoushan National Nature Reserve, field surveys were conducted to assess prey distribution in the reserve. Twelve permanent transects were set in three distinct functional zones from February to April 2012 and May to July 2013. A total of 112 ungulate signs were recorded on these transects. In addition, 20 camera traps were used to survey ungulates and predators in 2012, while the following year we extended the survey site by using 30 cameras. Overall, 6641 capture events on 2930 camera days were obtained, presenting a variety of ungulate species: muntjak (Muntiacus muntjak), tufted deer (Elaphodus cephalophus), serow (Capricornis sumatraensis) and wild boar (Sus scrofa). Population structure and composition of ungulates was compared in different functional zones using a single factor of variance analysis in SPSS software. Significant differences in the distribution of ungulates were recognized between the core zone and experimental zone, but not in other zones due to differences in habitat types and management practices of the nature reserve. Using ArcGIS analysis and Salford Predictive Modeler software, we ran several predictive models to understand which areas are most suitable for ungulates. We conclude that muntjac and wild boar are mainly distributed in the experimental zone, serow are more common in the core zone, while tufted deer are located evenly in the three functional zones. Finally, suggestions for effective and feasible management strategies and techniques for Matoushan National Nature Reserve were recommended based on the results and analysis in this study.  相似文献   
778.
Based on the simulation with the Ocean-Atmosphere Coupled Model CCSM and Ocean Model POP under the greenhouse gas emission scenario of the IPCC SRES A2 (IPCC, 2001), and on the earth crust subsidence and glacier melting data, the relative sea level change is obtained along the coast of China in the 21st century. Using the SRTM elevation data the submergence of coastal low land is calculated under the extreme water level with a 100-year return period. The total flooding areas are 98.3×103 and 104.9×103 km2 for 2050 and 2080, respectively. For the three regions most vulnerable to extreme sea level rise, i.e., the coast of Bohai Bay, the Yangtze River Delta together with neighboring Jiangsu Province and northern Zhejiang Province, and the Pearl River Delta, the flooded areas are 5.0×103, 64.1×103 and 15.3×103 km2 in 2050 and 5.2×103, 67.8×103 and 17.2×103 km2 in 2080, respectively.  相似文献   
779.
A households′production behavior directly influences the quality of the environment and determines the successful development of nature reserves.Meanwhile,the households′production behaviors are complicated by interrelated factors,such as protection attitudes,resource endowment,and family wealth.This research evaluated households near the Crested Ibis National Nature Reserve in Shaanxi Province,acquiring data from 436 households around Yang County and Ningshan County in the south slope of Qinling Mountains,China.Based on the collected data,we developed a structural equation model to evaluate the coupling relationships among households′ protection attitudes,production behaviors,resource endowment,and family wealth.The results showed that:1) households with great resource endowment had more negative attitudes,probably due to their greater protection costs;2) the households with higher education levels had worse protection attitudes;3) the households with more family wealth were likely to use fewer fertilizers,pesticides,and firewood;4) the households with more resource endowment showed less production and management behaviors;5) the enhancement of households’ attitudes improved production behaviors to protection the environment,but the effects were not statistically significant.Our results provide a basis for the government’s protection policy making,exploring the effective management measures that are beneficial for both nature reserve management and community development.  相似文献   
780.
The Magnuson-Stevens Fishery Conservation and Management Act (1976), opened a new era of federal fishery management in the United States. It was enacted primarily to establish a system for conserving and managing fisheries in the new 200-mile (EEZ). The US assumed exclusive authority for managing all fisheries within the EEZ, except for highly migratory species such as tunas and billfishes. Within the framework of the Act, eight Regional Fishery Management Councils (Regional Councils) were created, which are responsible for preparing Fisheries Management Plans (FMPs) in federal waters under their jurisdiction. Each FMP must meet a series of National Standards (NSs) for conservation and management. The Act was reauthorized in 1996 with the passage of the Sustainable Fisheries Act (SFA), which aimed at fine tuning the fishery regulatory apparatus that was established under the original Act. This "fine tuning" involved increased attention to biological concerns, and removal of ambiguities within it. The Act was reauthorized again in 2007, mainly to provide for more clear directives and regulations to end overfishing. After more than thirty years since the Act was passed into law, the debate among conservationists, commercial and recreational fishery representatives, and politicians on the effectiveness of the Act in achieving its purported goals it still continues. Is the Act delivering on its promises? Do NSs reflect the most important priorities for the US fishery resources, conservation and sustainable exploitation? Do the Regional Councils represent all parties that should be involved in the fisheries resources management? The aim of this paper is to provide a critical analysis to answer these questions. This paper begins with a review of the Act and its background, followed by discussion and analysis of the Act's benefits and flaws. Finally, suggestions for the implementation of its structure and future directions in fishery management strategies are made.  相似文献   
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