基于熵值法的淮海经济区城市中心性评价

根据城市中心性的内涵,从生产中心性、商贸中心性、信息中心性、交通中心性和科教中心性5方面构建城市中心性的综合评价指标体系,并运用熵值法实证分析了淮海经济区主要城市的中心性.淮海经济区城市的中心性主要表现为生产、信息和科教方面的中心性,且区域差异较小,该区主要城市的中心性均不太显著,其中徐州的城市中心性相对较强.     

Analysis of Multiple Tourist Agents’ Symbiotic Relationship on the View of Tourist Enterprises Based on a Grey Correlation Model: A Case Study of Qinghai Lake,China

Tourism symbiosis is a social phenomenon consisting of many complex factors, and the reciprocal cooperation among multiple tourist agents at tourist destinations is the crux of the sustainable development of tourism. This study is from the perspective of tourist enterprises, and introduces the Symbiosis Theory of genecology. A quantitative evaluation is used to analyze both the equilibrium state of the combined symbiotic behavior routes and the behavior patterns of tourist enterprises with local governments, community residents, tourists and tourist enterprises around Qinghai Lake. The findings reveal: (1) the symbiotic behavior routes of the multiple tourist agents “E→G-R-T-E” in the Qinghai Lake area are constituted of intense symbiotic indications, while the maximum dimensionality of symbiotic interest of “E→G-R-T-E” is still in the state of disequilibrium and dissymmetry; (2) the symbiotic model of multiple tourist agents “E→G-R-T-E” in the Qinghai Lake area is an asymmetrically positive symbiotic model. It is proposed that, by establishing symbiotic mechanisms for guidance, decisions, supervisory control and profit distribution, the participation mechanism for multiple agents “E-G-R-T” can be further standardized. Moreover, tourist enterprises should be regarded as the primary agents to optimize the symbiotic model for “E→G-R-T-E” through the reinforcement of integrative supply and the construction of integrative effect, and finally promote the integrative symbiotic model of symmetrical reciprocity of the E-R-G-T model “driven by scenic areas, responsive to community residents, affected by local governments and enjoyed by tourists.”     

Impacts of Climatic Factors on Runoff Coefficients in Source Regions of the Huanghe River

Runoff coefficients of the source regions of the Huanghe River in 1956–2000 were analyzed in this paper. In the 1990s runoff of Tangnaihai Hydrologic Station of the Huanghe River experienced a serious decrease, which had at- tracted considerable attention. Climate changes have important impact on the water resources availability. From the view of water cycling, runoff coefficients are important indexes of water resources in a particular catchment. Kalinin baseflow separation technique was improved based on the characteristics of precipitation and streamflow. After the separation of runoff coefficient (R/P), baseflow coefficient (Br/P) and direct runoff coefficient (Dr/P) were estimated. Statistic analyses were applied to assessing the impact of precipitation and temperature on runoff coefficients (including Dr/P, Br/P and R/P). The results show that in the source regions of the Huanghe River, mean annual baseflow coefficient was higher than mean annual direct runoff coefficient. Annual runoff coefficients were in direct proportion to annual pre- cipitation and in inverse proportion to annual mean temperature. The decrease of runoff coefficients in the 1990s was closely related to the decrease in precipitation and increase in temperature in the same period. Over different sub-basins of the source regions of the Huanghe River, runoff coefficients responded differently to precipitation and temperature. In the area above Jimai Hydrologic Station where annual mean temperature is –3.9oC, temperature is the main factor in- fluencing the runoff coefficients. Runoff coefficients were in inverse relation to temperature, and precipitation had nearly no impact on runoff coefficients. In subbasin between Jimai and Maqu Hydrologic Station Dr/P was mainly affected by precipitation while R/P and Br/P were both significantly influenced by precipitation and temperature. In the area be-tween Maqu and Tangnaihai hydrologic stations all the three runoff coefficients increased with the rising of annual precipitation, while direct runoff coefficient was inversely proportional to temperature. In the source regions of the Huanghe River with the increase of average annual temperature, the impacts of temperature on runoff coefficients be-come insignificant.     

山东省肥城断块岩溶水系统地下水水化学特征及演化分析

地下水是肥城地区最主要的供水水源,近年来受到工农业生产、煤矿开采、闭坑、矿井排水等人类活动影响,肥城地区地下水动力场及化学场都发生了变化,为查明地下水的环境质量状况,文章在研究水文地质调查和样品采集分析基础上,综合运用数理统计方法、水化学方法（Piper三线图、Gibbs模型、矿物饱和指数、离子比例分析）等,探讨肥城断块地下水水化学特征及演化规律。结果表明：（1）研究区地下水均呈弱碱性,$ {\mathrm{C}\mathrm{a}}^{2+} $、$ {\mathrm{M}\mathrm{g}}^{2+} $、$ {{\mathrm{H}\mathrm{C}\mathrm{O}}_{3}}^{-} $和$ {\mathrm{S}\mathrm{O}}_{4}^{2-} $为主要离子,主要来源于方解石、白云石及石膏溶解;矿物饱和指数表明方解石和白云石绝大多数处于饱和状态,石膏和岩盐矿物呈溶解未饱和状态。（2）区内岩溶水化学类型主要为$ {\mathrm{H}\mathrm{C}\mathrm{O}}_{3}-\mathrm{C}\mathrm{a}\left(\mathrm{M}\mathrm{g}\right) $型,其次为$ {\mathrm{H}\mathrm{C}\mathrm{O}}_{3}·{\mathrm{S}\mathrm{O}}_{4}-\mathrm{C}\mathrm{a} $型和$ {\mathrm{H}\mathrm{C}\mathrm{O}}_{3}·\mathrm{C}\mathrm{l}-\mathrm{C}\mathrm{a} $型。孔隙水主要为$ {\mathrm{S}\mathrm{O}}_{4}·{\mathrm{H}\mathrm{C}\mathrm{O}}_{3}-\mathrm{C}\mathrm{a} $型、局部出现$ {\mathrm{S}\mathrm{O}}_{4}{·\mathrm{N}\mathrm{O}}_{3}-\mathrm{C}\mathrm{a} $型。河流水化学类型相对复杂,包括$ {\mathrm{S}\mathrm{O}}_{4}·{\mathrm{H}\mathrm{C}\mathrm{O}}_{3}-\mathrm{C}\mathrm{a}·\mathrm{N}\mathrm{a} $型、$ \mathrm{C}\mathrm{l}·{\mathrm{S}\mathrm{O}}_{4}-\mathrm{C}\mathrm{a}·\mathrm{N}\mathrm{a} $型等。（3）区内地下水中$ {\mathrm{C}\mathrm{l}}^{-} $、$ {\mathrm{S}\mathrm{O}}_{4}^{2-} $和$ {\mathrm{N}\mathrm{O}}_{3}^{-} $含量相比1999年、2013年显著升高。裂隙水及岩溶水水质整体较好,局部呈点状变差,孔隙水及河水水质普遍较差,影响区域地下水水质的主要因素有化肥施用、禽畜养殖、生活污水下渗以及煤矿排水等。     

黄河中游岩土侵蚀问题及防治对策探讨

黄河中游出露地层岩性主要有古生界奥陶系碳酸盐岩、石炭系和二叠系碎屑岩;中生界三叠系砂泥岩、侏罗系砂泥岩和白垩系砂泥岩;新生界古近系砂泥岩、新近系(原为第三系)红土及第四系风积黄土和现代风积沙。第四系黄土厚度大,结构松散,遇水易解体,具湿陷性,是黄河中游粗泥砂的主要物源;第四系风积沙分布于黄河中游北部,亦是黄河中游粗泥砂的主要物源。岩土侵蚀类型有五:一是风力侵蚀—风沙侵蚀;二是降雨对谷坡面的面状冲刷—坡面侵蚀;三是地表径流对谷底的侧蚀—沟谷侵蚀;四是滑塌对谷坡坡体的破坏—重力侵蚀;五是潜蚀。并对不同侵蚀类型提出了不同的防治对策。     

美国南极科研投入的统计分析及其对我国的启示

近些年来南极科研越来越受到世界各国的重视,作为《南极条约》的发起者和南极条约体系的管理者,美国始终站在南极科学研究前沿,对维护其国际南极事务领导地位有着重要意义。1953—2016年美国国家科学基金资助了7 759个南极科研项目,通过统计分析对项目投入进行以下4个方面的分析:南极项目投入、南极科研各学科投入、科研大项目以及合作机构。研究发现:(1)1953年至今,美国国家科学基金会(NSF)对美国南极科研项目的资助力度和重视力度不断增加,促进了美国南极政策的落实和发展;(2)美国各大科学指导机构出台的前瞻性文件对引领美国南极科考发展方向起到重要作用;(3)NSF充分利用各高等院校和研究机构的资源设施,搭建科研支撑平台,与之展开长期南极科研项目合作;(4)NSF重视科研大项目的开展,这些大项目站在南极科学前沿,引领美国南极科研更好地发展;(5)NSF通过学校、社会、媒体多个渠道开展南极教育,增进群众对南极了解并培养科研人员来维护美国在南极的科考领先地位。上述研究发现为中国南极科研政策制定提供了相应的启示。     

近50a来塔里木河干流年径流量变化趋势及预测

根据塔里木河干流1957-2008年的年径流量监测数据,利用Mann-Kendall非参数技术检验和R/S法,对干流年径流量时间序列变化趋势进行分析,并在此基础上采用滑动t检验法和Mann-Kendall法对其突变点进行检验,最后运用方差分析外推法和叠加趋势预测模型对干流水文周期和未来径流量变化进行分析和预测.结果显示...     

松潘地区岩金统计成矿予测中泛克立格法的应用

川西北地区是国内重要的岩金普查靶区。本文对松潘地区的地质特征,泛克立格法原理,及在本区的应用情况作了介绍,对主要计算步骤,给出基本结果,对计算获得的有意义异常区,进行地质解释,并将此方法与趋势面分析进行对比。     

塔里木盆地绿洲形成与演变

塔里木盆地的绿洲按形成历史可划分为古绿洲、旧绿洲和新绿洲,它们分别代表绿洲发展演变的三个阶段。本文对绿洲未来演变趋势作了预测,探讨了盆地古绿洲衰亡原因、认为除了风沙、盐碱及河流改道等自然原因外,人类活动引起的地表水资源时空分配发生变化是主要原因。     

粤港澳大湾区人口老龄化时空特征及其经济效应

中国新时代“两个十五年”的现代化强国战略周期,恰恰是快速人口老龄化纵深发展期,人口年龄结构快速老龄化与经济社会之间的发展不平衡矛盾将日益严峻。本文利用广东省第四次、第五次、第六次人口普查资料、2015年广东省1%人口抽样调查资料、香港统计年刊和澳门统计年鉴数据,运用空间自相关分析法、柯布-道格拉斯生产函数和空间回归等方法,研究2000—2015年粤港澳大湾区人口老龄化的时空特征及其经济效应,结果表明：① 粤港澳大湾区人口老龄化进程慢于广东省,更慢于全国,但于2015年已进入老年型I期。② 粤港澳大湾区老龄化呈动态演变特征,空间上以香港和江门为起点,经西北向北扩散的“C”型分布模式,高收入城市以澳门和香港为起点向北扩散,最终形成中心-外围的空间分布格局。③ 粤港澳大湾区人口老龄化对经济增长具有负向影响,老龄人口增加1%,人均GDP降低3%。人均固定资本投入和人均人力资本投入有正的经济效应,人均人力资本投入带来的正向效应要大于人均固定资本投入。鉴于此,粤、港、澳三地应建立起协同治理模式,构建跨境的养老合作机制;促进产业结构升级,充分利用人力资本促进技术创新,并正确评估不同阶段人口老龄化对经济增长的影响,妥善处理好人口老龄化与经济之间的关系至关重要。