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Spatial Agglomeration and Diffusion of Population Based on a Regional Density Function Approach:A Case Study of Shandong Province in China
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作者 Xiaohan Zhao Yanbin Chen 《Journal of Geographical Research》 2023年第3期61-80,共20页
Population density functions have long been used to describe the spatial structure of regional population distributions.Several studies have been conducted to examine the population distribution in Shandong Province,C... Population density functions have long been used to describe the spatial structure of regional population distributions.Several studies have been conducted to examine the population distribution in Shandong Province,China,but few have applied regional density functions to the analysis.Therefore,based on the 2000,2010,and 2020 population censuses,this study used monocentric and polycentric regional density functions to study the characteristics of population agglomeration and diffusion in Shandong.This is followed by an in-depth discussion based on population growth rate data and hot-and cold-spot analyses.The results showed that the Shandong Province population was spatially unevenly distributed.Population growth rates were higher in urban centers and counties,with more significant changes in population size in the eastern coastal areas than in the inland areas.As verified in this study,the logarithmic form of the single-center regional density function R2 was greater than 0.8,which was in line with the population spatial structure of Shandong Province.During the study period,the estimated population density of the regional center and the absolute value of the regional population density gradient both increased,indicating a clear and increasing trend of centripetal agglomeration of regional centers over the study period.Overall,the R2 value of the multicenter region density function was higher than that of the single-center region density function.The polycentric regional density function showed that the population density gradient of some centers had a downward trend,which reflected the spatial development trend of outward diffusion in these centers.Meanwhile,the variation in the estimated population density and the population density gradient exhibited differences in the central population distribution patterns at different levels. 展开更多
关键词 regional density functions Population spatial structure shandong province
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Erratum to: Geological characteristics of the Sizhuang gold deposit in the region of Jiaodong, Shandong Province—A study on tectonogeochemical ore prospecting of ore deposits 被引量:1
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作者 QIAN Jianping CHEN Hongyi MENG Yong 《Chinese Journal Of Geochemistry》 EI CAS 2012年第1期109-110,共2页
关键词 A study on tectonogeochemical ore prospecting of ore deposits Erratum to Geological characteristics of the Sizhuang gold deposit in the region of Jiaodong shandong province
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Study on Development of the West of Shandong Province Based on Overall Regional Development Planning Pattern
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作者 Pang Jiewu 《Chinese Journal of Population,Resources and Environment》 2009年第4期82-87,共6页
The overall regional development planning pattern has been considered to be a new and effective pattern as for development of provincial economy.The article analyzed the current conditions of the west of Shandong Prov... The overall regional development planning pattern has been considered to be a new and effective pattern as for development of provincial economy.The article analyzed the current conditions of the west of Shandong Province and tried to find the generation mechanisms of current non-balanced economic development of Shandong Province.And then approaches to regional development were put forward according to the theory of regional development pattern as a whole. 展开更多
关键词 overall regional development planning pattern west of shandong province regional economy
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Development Plan for Under- forest Economy of Henan Province Based on Central Plains Economic Region 被引量:3
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作者 Xiaodong ZHAO Yimin ZHAO 《Asian Agricultural Research》 2016年第2期34-38,共5页
Firstly,this paper analyzed current situations,major practice and existing problems of under-forest economy in Henan Province.Then,it made an in-depth discussion of guiding thought,principle and objectives,constructio... Firstly,this paper analyzed current situations,major practice and existing problems of under-forest economy in Henan Province.Then,it made an in-depth discussion of guiding thought,principle and objectives,construction task and safeguarding measures of the underforest economic development plan. Besides,it analyzed benefits of the under-forest economic development plan. By 2017,the area of underforest economic land will reach 1. 60 million hm2,create output value of 155. 2 billion yuan( accounting for more than 20% of forest output value),provide 3. 27 million jobs,and will greatly increase ecological carrying capacity of construction and development of the Central Plains Economic Region( CPER). 展开更多
关键词 WORDS Under-forest ECONOMY Plan central PLAINS Economic region(CPER) Analysis HENAN province
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Suitability evaluation of regional coastal ecotourism based on SOM neural network model: a case study of Qingdao, Yantai, Weihai and Rizhao of Shandong Province 被引量:2
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作者 CHENG Zhen-yu 《Ecological Economy》 2010年第3期239-246,共8页
Development of coastal ecotourism has been a,focus of Shandong government, and the suitability evaluation of regional eoastai ecotourism is crucial for the reasonable plan and sustainable development of Shandong coast... Development of coastal ecotourism has been a,focus of Shandong government, and the suitability evaluation of regional eoastai ecotourism is crucial for the reasonable plan and sustainable development of Shandong coastal ecotourism. By using MATLAB language to establish a SOM neural network model, this' paper evaluates the eoastal ecotourism suitability of four regions, Qingdao. Yantai, Weihai and Rizhao of Shandong Province and divides 33 subordinate regions of those four cities into four categories, i.e. regions poorly suitable for ecotourism resources, regions highly suitable for coastal ecotourism, regions secondly suitable for coastal ecotourism, regions ordinarily suitable.for coastal ecotourism, Related suggestions on development of regional coastal ecotourism have been given in the final conclusions. 展开更多
关键词 SOM neural network shandong province Suitability evaluatian of regional coastal ecotourism
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ENVIRONMENTAL FEATURES AND WATERENVIRONMENTAL PROBLEMS IN THE CONTIGUOUSREGION OF JIANGSU,SHANGDONG,HENANAND ANHUI PROVINCES
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作者 季子修 于秀波 张琛 《Chinese Geographical Science》 SCIE CSCD 1999年第1期63-69,共7页
Owing to intensive human activities and the floods of the Huaihe River in historic peiod, the contiguous region of Jiangsu, Shandong, Henan and Anhui provinces is suffering from a variety of environmental problems and... Owing to intensive human activities and the floods of the Huaihe River in historic peiod, the contiguous region of Jiangsu, Shandong, Henan and Anhui provinces is suffering from a variety of environmental problems and naturaldisasters, of which water pollution and drought-flood disasters are most observable. Considering the special location andenvironmental status of the contiguous region, advices are proposed in the paper: perfecting trans-regional managementssystem of water environment incorporating basin management agencies in local government activities; strengthening cooperation of two agencies: water conservancy agency and environment protection agency; enhancing integrated control ofwater pollution and flood-drought disasters; taking the interests of the whole river into acount and paying attention to bothstorage and drainage; broadening sources of water supply and inceasing water delivery; controlling pollutant discharge,developing water saving production system. 展开更多
关键词 environmental problems drought and flood DISASTERS WATER pollution contiguous region of Jiangsu shandong HENAN and ANHUI provinceS
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Diagnostic Analysis on a Regional Rainstorm Weather in North-central Henan Province 被引量:1
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作者 SUN Zhong-yi ZHANG Zhen LI Ji-hua 《Meteorological and Environmental Research》 CAS 2011年第6期19-23,共5页
[Objective] The research aimed to analyze a regional rainstorm weather process in north-central Henan Province. [Method] Based on the conventional meteorological observation data and the rainfall data of Henan Meteoro... [Objective] The research aimed to analyze a regional rainstorm weather process in north-central Henan Province. [Method] Based on the conventional meteorological observation data and the rainfall data of Henan Meteorological Station, the diagnostic analysis of atmospheric thermodynamics and dynamics on a rainstorm weather process in north-central Henan Province on July 19, 2010 was carried out. The characteristics of physical quantity field and the evolution of weather situation in north-central Henan Province when the rainstorm happened were studied. [Result] Western Pacific subtropical high strengthened to extend westward. The dynamic uplifting of low vortex at the middle and low layers, the strong water vapor transportation of southwest low-level jet caused the regional rainstorm weather process in north-central Henan Province. The diagnostic results of physical quantity showed that the deep, thick wet layer and the sustained water vapor convergence provided the abundant water vapor for rainstorm generation. The positive vorticity advection center developed and spread from northwest to southeast, which was favorable for the development of vertical movement. The structure maintenance of positive vorticity at the middle and low layers, negative vorticity at the middle and high levels provided the power condition for the regional rainstorm generation. The pumping effect of convergence at the middle and low layers, divergence at the high layer was favorable for the strengthening of vertical ascending motion at the low layer. The uplifting effect of dew point front at the middle and low layers triggered the release of unstable energy. The confrontation of warm and cold air was one of the important reasons for the regional rainstorm. TBB characteristic analysis showed that TBB was from -60 to -50 ℃ in north-central Henan Province in the whole strong precipitation time, and the moving speed was equivalent to that of southwest vortex. The low-value belt of TBB corresponded with the rainstorm occurrence zone in Henan, and the minimum-value center of TBB was basically consistent with the strongest center of precipitation. [Conclusion] The research provided the scientific basis for the short-term forecast of rainstorm. 展开更多
关键词 North-central Henan province regional rainstorm Weather process Diagnostic analysis China
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Late Carboniferous-Early Permian Volcanic Event Deposits and Stratigraphic Correlation in Shandong Province and Its Adjacent Regions 被引量:3
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作者 Zhong Rong, Institute of Geomechanics, Chinese Academy of Geological Sciences, BeijingSun Shanping and Fu Zeming China University of Geosciences, Beijing Xu Niansheng, Xu Heling and Zhong Rong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1996年第4期380-394,453,共16页
Deposits of 10 volcanic events of 6 stages have been discovered by the authors after detailed field and lab studies of the Benxi and Taiyuan Formations in Shandong Province and its adjacent regions. They show certain ... Deposits of 10 volcanic events of 6 stages have been discovered by the authors after detailed field and lab studies of the Benxi and Taiyuan Formations in Shandong Province and its adjacent regions. They show certain temporal-spatial distribution characteristics. Volcanic fragments were probably derived from two different volcanic sources north and south of the North China Platform, while the magma of the two volcanic sources was probably derived from the lower crust. A new stratigraphic correlation scheme is put forward for the Benxi and Taiyuan Formations in this region on the basis of previous biostratigraphic work with the regionally widespread volcanic event layers as the marker bed for the isochronous stratigraphic correlation on a super-regional scale and in conjunction with the maximum transgressive event layers. 展开更多
关键词 volcanic event deposits Late Carboniferous-Early Permian Benxi and Taiyuan Formations stratigraphic correlation volcanic source shandong province and its adjacent regions
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基于REOF分析的山东省年降水区域特征及趋势分析
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作者 任建成 谷山青 卢晓宁 《水土保持研究》 CSCD 北大核心 2024年第1期224-231,共8页
[目的]探究山东省不同气候分区年降水量的时空特征,为该地区气候分析、防灾减灾提供更加区域性的参考依据。[方法]根据山东省95个国家地面气象观测站1991—2020年降水年值数据,首先对山东省年降水场进行气候分区,然后通过相关统计方法... [目的]探究山东省不同气候分区年降水量的时空特征,为该地区气候分析、防灾减灾提供更加区域性的参考依据。[方法]根据山东省95个国家地面气象观测站1991—2020年降水年值数据,首先对山东省年降水场进行气候分区,然后通过相关统计方法分析各分区降水的时空变化特征。[结果](1)山东省各降水模态降水偏少的年份更多,降水偏多的年份降水强度更大,年代际变化均较为明显,但各模态降水偏多偏少的年份分布及强度变化有所不同。(2)山东省年降水量大致由东南向西北递减,年降水场划分为东南沿海区(Ⅰ区)、西北平原区(Ⅱ区)和中部山地区(Ⅲ区)3个区域,各降水分区年降水均呈不显著增加趋势,趋势率各不相同,突变均不明显。(3)山东省各降水分区年降水量均具有较为明显的周期性特征,东南沿海区年降水场存在2个较为明显的能量中心,中心尺度均为2~3 a,未来变化具有强持续性;西北平原区年降水场存在3个较为明显的能量中心,中心尺度分别为5~7 a, 3 a和2~3 a,未来变化具有持续性;中部山地区年降水场存在2个较为明显的能量中心,中心尺度分别为2~3 a, 6 a,未来变化具有强持续性。[结论]山东省降水偏少的年份更多,降水偏多的年份降水强度更大,年降水场大致可分为3个分区,各分区年降水量均呈不显著增加趋势,均具有较为明显的周期性特征,且未来变化均具有持续性。 展开更多
关键词 年降水 区域特征 旋转经验正交函数 重标极差分析法 山东省
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Reconstructing Spatial Distribution of Historical Cropland in China′s Traditional Cultivated Region: Methods and Case Study 被引量:4
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作者 YANG Xuhong GUO Beibei +2 位作者 JIN Xiaobin LONG Ying ZHOU Yinkang 《Chinese Geographical Science》 SCIE CSCD 2015年第5期629-643,共15页
As an important part of land use/cover change(LUCC), historical LUCC in long time series attracts much more attention from scholars. Currently, based on the view of combining the overall control of cropland area and ... As an important part of land use/cover change(LUCC), historical LUCC in long time series attracts much more attention from scholars. Currently, based on the view of combining the overall control of cropland area and ′top-down′ decision-making behaviors, here are two global historical land-use datasets, generally referred as the Sustainability and the Global Environment datasets(SAGE datasets) and History Database of the Global Environment datasets(HYDE datasets). However, at the regional level, these global datasets have coarse resolutions and inevitable errors. Considering various factors that influenced cropland distribution, including cropland connectivity and the limitation of natural and human factors, this study developed a reconstruction model of historical cropland based on constrained Cellular Automaton(CA) of ′bottom-up′. Then, an available labor force index is used as a proxy for the amount of cropland to inspect and calibrate these spatial patterns. Applied the reconstruction model to Shandong Province, we reconstructed its spatial distribution of cropland during 8 periods. The reconstructed results show that: 1) it is properly suitable for constrained CA to simulate and reconstruct the spatial distribution of cropland in traditional cultivated region of China; 2) compared with ′SAGE datasets′ and ′HYDE datasets′, this study have formed higher-resolution Boolean spatial distribution datasets of historical cropland with a more definitive concept of spatial pattern in terms of fractional format. 展开更多
关键词 traditional cultivated region historical cropland reconstruction constrained Cellular Automaton (CA) shandong province
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Influencing Factors on Farming System Development in Shandong Province 被引量:1
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作者 LIU Yan1,NING Tang-yuan1,ZHOU Xun-bo1,2 1.State Key Laboratory of Crop Biology,Shandong Key Laboratory of Crop Biology,Shandong Agricultural University,Taian 271018,China 2.Key Laboratory of Ecosystem Network Observation and Modeling,Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China 《Asian Agricultural Research》 2010年第10期60-64,共5页
The developmental situation of the farming system in Shandong Province is introduced.At present,Shandong Province is at the semi-intensive,semi-commercial and semi-sufficiency level of farming system.Eastern coast and... The developmental situation of the farming system in Shandong Province is introduced.At present,Shandong Province is at the semi-intensive,semi-commercial and semi-sufficiency level of farming system.Eastern coast and central Shandong agricultural zones are moving in the direction of modern farming system,having formed a preliminary new pattern of the coordinated development of grain,feedstuff,economic and other crops.Influencing factors on the development of farming system in Shandong Province is analyzed,which are agricultural production condition and input level,population and food,policy measures,development of natural resources and regions,agricultural industrialization and urbanization level,and scientific and technological level.Total population will be within 100 million at the year 2020;per capita annual share of grain will be 475 kilograms;and there is great pressure on grain production.Therefore,we must change the pattern of agricultural development and accelerate the establishment of modern farming system.Agricultural machinery,water conservancy projects,and chemical fertilizer application have greatly affected the development of farming system.Improvement of production conditions has promoted the adjustment of agricultural structure,increased the planting ratio of winter wheat-summer maize,and improved multiple-cropping index.Development of agricultural industrialization has promoted the transfer of rural labor force and the establishment of modern farming system;while the unbalanced development of cities has restricted the establishment of modern farming system.Therefore,the appropriate policy,scientific and rational regional distribution,and advanced science and technology can help to set up the modern farming system in Shandong Province. 展开更多
关键词 shandong province STRUCTURE adjustment regionAL DE
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Characteristics of mantle branch structure in western Shandong and its roles in minerogenesis and ore-controlling 被引量:4
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作者 孙爱群 胡华斌 +4 位作者 牛树银 毛景文 王宝德 李英平 王来明 《Chinese Journal Of Geochemistry》 EI CAS 2006年第4期340-353,共14页
This work deals with the characteristics of mantle branch structure in western Shandong Province, China, with respect to the distribution characteristics and ages of the regional strata, the development of ring-like a... This work deals with the characteristics of mantle branch structure in western Shandong Province, China, with respect to the distribution characteristics and ages of the regional strata, the development of ring-like and radial faults, the development of gently inclined detachment-slip structures in the axial part, mantle-source magmatic activities, regional petrology, petrochemistry and isotope geology. The study indicated that the N-W sharply plunged ductile shear zone in the region of western Shandong cuts through the mantle rocks detached from the deep-seated North China mantle sub-plume, hence leading to unloading in response to depressurization and thereafter the formation of anatexis magma. The intense and complete magmatic evolution series not only manifests a variation trend of alkalinity of magma from high to low and its intrusive depth from deep to shallow, but also reflects that the wall-rock alteration shows a general evolution trend from strong to weak. The evolution of mantle structure played an important role in controlling endo-mineralogenesis, accompanied with the rise of the country rocks. As a result, typical mantle branch structures were formed as observed in western Shandong. At the top of the mantle branch structure was developed an obvious detachment-tilt fault block, and some endogenic ores, at the same time, were uplifted onto the shallow levels. 展开更多
关键词 地幔分支结构 地幔热流柱 地球物理学 地质学
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山东省大豆生产地域格局变化及影响因素分析
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作者 刘锋 赵鑫喆 +4 位作者 殷芳 杨萍 郭征华 张惠莉 张晓艳 《大豆科学》 CAS CSCD 北大核心 2024年第6期793-804,共12页
为给山东省大豆生产的可持续发展提供科学决策依据,本研究运用数理统计和区域比较优势测算方法,分析了山东省大豆生产地域格局的变化特征及其影响因素。结果表明:山东省大豆播种面积从1949年的191.54万hm^(2)下降到2022年的21.496万hm^(... 为给山东省大豆生产的可持续发展提供科学决策依据,本研究运用数理统计和区域比较优势测算方法,分析了山东省大豆生产地域格局的变化特征及其影响因素。结果表明:山东省大豆播种面积从1949年的191.54万hm^(2)下降到2022年的21.496万hm^(2),降幅达88.78%,自2000年以来,降幅为53.09%;大豆总产量从1949年的93.4万t下降到2022年的58.10万t,降幅为37.79%,自2000年以来,降幅为44.43%;山东省大豆单产水平明显高于全国平均水平,1978—2022年,单产增幅为163.01%,高出全国76.06%。山东大豆种植区域,由主要分布在除了滨州的沿海地市及菏泽、枣庄和临沂、济宁等地市,向鲁中地区转移,主要原因是耕地面积的减少、大豆生产的人工成本较高、净利润为负值且低于同期作物。山东省在具有生产大豆的优势背景下,也存在大豆种植收益比较低、产品竞争力弱、单产水平提高难度加大等挑战,文中最后提出了山东省发展大豆产业的对策建议。 展开更多
关键词 山东省 大豆生产特征 地域格局变化 影响因素
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湘中北晚二叠世石煤元素地球化学特征
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作者 张卫国 杨建业 +2 位作者 侯恩科 周佳瑞 李书琳 《西安科技大学学报》 CAS 北大核心 2024年第4期738-747,共10页
湘中北地区晚二叠世吴家坪组赋存少量石煤,其属性特征鲜明。为揭示湘中北地区石煤元素地球化学特征,采集4个湘中北地区晚二叠世石煤样品,利用X射线衍射仪、带能谱的扫描电镜、X射线荧光光谱仪、电感耦合等离子质谱仪和逐级化学提取试验... 湘中北地区晚二叠世吴家坪组赋存少量石煤,其属性特征鲜明。为揭示湘中北地区石煤元素地球化学特征,采集4个湘中北地区晚二叠世石煤样品,利用X射线衍射仪、带能谱的扫描电镜、X射线荧光光谱仪、电感耦合等离子质谱仪和逐级化学提取试验,测定了石煤样品的矿物成分、常量元素和微量元素含量,进行了微量元素赋存状态分析。结果表明:湘中北地区晚二叠世石煤高灰特征显著,石煤全硫含量差异性大,以硫化铁为主,有机硫次之;石煤矿物种类较少,以石英为主,陆源碎屑输入量极大;石煤高度富集V、Cr、As、Cd、Mo和Sb,其中Cd达到了上地壳丰度的555倍;石煤微量元素赋存特征复杂,其中Ni、Zn、Sr、Mo、Cd赋存状态多样,Li、V、Cr、Cu、Rb、Zr、Ba、U和REEs赋存状态相对简单;根据湘中北晚二叠世石煤元素地球化学特征认为石煤沉积于被动大陆边缘区域,接受陆源碎屑输入,沉积物源区以长英质酸性岩为主。石煤具有海相环境沉积物特征,沉积过程受海水影响强烈,相对稳定的缺氧环境,为V、Mo等元素自生富集提供了条件。 展开更多
关键词 湘中北 石煤 元素 地球化学
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基于GIS分析的鲁中南低山丘陵区地质灾害风险评价
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作者 王华锋 陈洪海 +5 位作者 贾琛 马龙 亓贞才 张晓飞 马建伟 张晔 《山东国土资源》 2024年第10期66-72,共7页
为更好地开展山东省鲁中南低山丘陵区地质灾害综合防治工作,本文在地质灾害风险普查的基础上,运用信息量模型,结合GIS分析建立了区域地质灾害易发性和风险性评价体系。本次评价体系选取了地形坡度、起伏度等8个不同的评价指标,得出了地... 为更好地开展山东省鲁中南低山丘陵区地质灾害综合防治工作,本文在地质灾害风险普查的基础上,运用信息量模型,结合GIS分析建立了区域地质灾害易发性和风险性评价体系。本次评价体系选取了地形坡度、起伏度等8个不同的评价指标,得出了地质灾害的易发性分级及分布范围。叠加研究区利用皮尔逊三型水文模型得到的不同重现期下的降水强度,进行危险性评价。危险性叠加易损性,得到风险性评价,为研究区地质灾害防治提供科学依据。结果显示,随着降水量的增大,地质灾害发生的概率就越大。 展开更多
关键词 GIS 易发性评价 危险性评价 风险性评价 鲁中南
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太行林蛙地理分布厘定 被引量:1
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作者 邱显淳 周圣博 +11 位作者 齐硕 王锦泽 周瑜 陆宇燕 徐克阳 袁静 梁咏亮 朱亚超 李静尧 王兴哲 史静耸 李丕鹏 《四川动物》 北大核心 2024年第3期326-335,共10页
太行林蛙Rana taihangensis目前已知分布在河南、河北、北京和辽宁等地。根据采自宁夏固原和山东青岛的标本,报道宁夏回族自治区和山东省太行林蛙新分布记录。根据采集自内蒙古通辽和辽宁阜新的太行林蛙标本对其进行形态学补充描述。基... 太行林蛙Rana taihangensis目前已知分布在河南、河北、北京和辽宁等地。根据采自宁夏固原和山东青岛的标本,报道宁夏回族自治区和山东省太行林蛙新分布记录。根据采集自内蒙古通辽和辽宁阜新的太行林蛙标本对其进行形态学补充描述。基于不同地区蛙属Rana标本线粒体cyt b基因的分子系统发育分析结果显示,山西省和陕西省为此前尚未记录的太行林蛙分布区。由此可将太行林蛙在中国的分布范围增加4个省(自治区),目前太行林蛙的分布范围则包括河南省、河北省、北京市、天津市、辽宁省、山东省、山西省、陕西省、宁夏回族自治区和内蒙古自治区。 展开更多
关键词 宁夏回族自治区 山东省 无尾目 分布新记录种 中国林蛙
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鲁中南山区侵蚀性降雨及典型作物对坡面产流产沙影响研究 被引量:2
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作者 张哲 方政 +4 位作者 董智 吴其聪 潘嘉琛 刘超 安淳淳 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期69-76,共8页
为研究降雨量、降雨历时、降雨强度等降雨因素及典型作物对坡面产流产沙的影响,基于K-均值聚类分析法对山东省泰安市东周小流域2014-2020年77次侵蚀性降雨进行分类,并进一步分析不同降雨类型下不同作物产流产沙特征及对各降雨指标的响应... 为研究降雨量、降雨历时、降雨强度等降雨因素及典型作物对坡面产流产沙的影响,基于K-均值聚类分析法对山东省泰安市东周小流域2014-2020年77次侵蚀性降雨进行分类,并进一步分析不同降雨类型下不同作物产流产沙特征及对各降雨指标的响应.结果表明:①研究区侵蚀性降雨可以分为Ⅰ型(小雨量、短历时、大雨强)、Ⅱ型(大雨量、长历时、小雨强)、Ⅲ型(中雨量、中历时、小雨强)3类.各降雨频率为67.53%,3.9%,28.57%,占研究期内总降雨量的44.2%,14.02%,41.78%.②各径流小区产流和土壤流失量从大到小依次为大豆、裸地、地瓜、花生,花生和地瓜对径流和泥沙的削减效果相对较好.在Ⅱ型条件下,各小区产流产沙量最大,Ⅲ型次之,Ⅰ型最小;但当Ⅰ型和Ⅲ型雨频率较高时,产流产沙量也较大.③对坡面产流产沙影响最大的因素为降雨量,当作物种类不同时,影响次之的因素有所差别.径流对降雨因素的响应程度高于土壤流失量,控制产流发生可在一定程度上有效降低土壤流失量. 展开更多
关键词 侵蚀性降雨 典型作物 产流 产沙 鲁中南山区
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鄂中丘陵区不同林龄马尾松人工林林下植物多样性与土壤理化性质关系
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作者 陈会玲 勾蒙蒙 +5 位作者 刘常富 雷蕾 胡建文 朱粟锋 斛如媛 肖文发 《生态环境学报》 CSCD 北大核心 2024年第10期1525-1533,共9页
为深入了解马尾松人工林林下植物多样性与土壤理化性质的关系,采用“空间代时间”法在鄂中丘陵区选取不同林龄(5、12、28、37、56 a)马尾松(Pinus massoniana)人工林样地,通过分析林下灌草层物种丰富度、Shannon-Wiener多样性、Simpson... 为深入了解马尾松人工林林下植物多样性与土壤理化性质的关系,采用“空间代时间”法在鄂中丘陵区选取不同林龄(5、12、28、37、56 a)马尾松(Pinus massoniana)人工林样地,通过分析林下灌草层物种丰富度、Shannon-Wiener多样性、Simpson优势度和Pielou均匀度及土壤(0-10 cm)理化性质的差异及彼此间的相关性,探索土壤理化性质对林下植物多样性的影响。结果表明:不同林龄灌草层植物多样性差异显著,灌木层植物多样性随林龄的增加而先增加后减少再增加,28 a的Shannon-Wiener多样性和Pielou均匀度分别高于5 a的92.02%和86.67%;草本层各植物多样性随林龄的增加而先减后增,5 a显著高于其他林龄。灌木层物种丰富度、Shannon-wiener多样性、Simpson优势度和Pielou均匀度显著高于草本层(5 a除外)。不同林龄土壤理化性质差异显著,pH、含水量、全量养分和速效钾含量随林龄的增加而先减后增,pH、全磷和全钾含量在5 a显著高于其他林龄。有机碳与碱解氮随林龄的增加而先增后减,37 a的显著高于5、12和28 a的。不同林龄马尾松林下灌草层植物多样性与pH、全磷和全钾含量显著相关。冗余分析表明土壤理化性质分别解释灌木层和草本层植物多样性的89.1%和78.5%。逐步回归分析表明增加全磷含量可提高草本层植物多样性,pH、全磷、全钾和林分密度可调控灌木层植物多样性。综上,马尾松人工林林下植物多样性受土壤理化性质的影响,全磷是调控该地区林下植物多样性的关键因子,加强磷肥的管理可提升林下植物多样性。 展开更多
关键词 马尾松人工林 林龄 植物多样性 土壤理化性质 鄂中丘陵区
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山东企业OFDI的区域差异及其影响因素分析 被引量:3
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作者 袁其刚 郜晨 张伟 《重庆交通大学学报(社会科学版)》 2018年第6期73-82,共10页
不同地区企业对外直接投资行为的差异有诸多原因。首先按照OFDI流量和经济发展水平将山东省十七地市分成发达和欠发达两大区域,基于2006—2015年这十七地市对外直接投资的面板数据,利用泰尔指数衡量山东省OFDI区域间差异和区域内差异的... 不同地区企业对外直接投资行为的差异有诸多原因。首先按照OFDI流量和经济发展水平将山东省十七地市分成发达和欠发达两大区域,基于2006—2015年这十七地市对外直接投资的面板数据,利用泰尔指数衡量山东省OFDI区域间差异和区域内差异的程度以及各自的贡献率,再对各区域OFDI的影响因素进行实证研究。结果表明:经济发展水平和金融发展水平对山东省企业OFDI有促进作用;工业化程度和研发水平对发达区域影响显著,而对欠发达区域影响均不显著;文化发展水平对发达区域影响不显著,而对欠发达区域影响显著;外商直接投资对这两型区域对外直接投资的影响均不显著。最后,对山东省各区域OFDI的影响因素进行总结并为其发展提出相关建议。 展开更多
关键词 山东省 ofDI 区域差异 泰尔指数
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山东省交通运输-区域经济-生态环境耦合协调时空演变研究
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作者 来逢波 孙婷 +3 位作者 李庆军 刘明 杨禛 程钰 《济南大学学报(自然科学版)》 CAS 北大核心 2024年第5期526-532,540,共8页
为了研究山东省交通运输、区域经济和生态环境3个子系统发展水平及其耦合协调发展状态时空分异特征,基于2011—2020年山东省交通运输、区域经济和生态环境的面板数据,运用熵值法、耦合协调度模型和核密度估计方法,研究山东省交通运输-... 为了研究山东省交通运输、区域经济和生态环境3个子系统发展水平及其耦合协调发展状态时空分异特征,基于2011—2020年山东省交通运输、区域经济和生态环境的面板数据,运用熵值法、耦合协调度模型和核密度估计方法,研究山东省交通运输-区域经济-生态环境的耦合协调度的时空分异特征及其演化规律。结果表明:山东省交通运输、区域经济、生态环境系统的耦合协调度处于稳步上升趋势,生态环境的综合评价水平始终领先于交通运输综合发展水平和区域经济综合发展水平;全省各地市的交通运输、区域经济以及生态环境发展不均衡,在空间上形成双核心和“中心-外围”空间分布特征,青岛、济南在交通运输-区域经济-生态环境系统的耦合协调度上一直保持高位,其他城市耦合协调度发展水平呈现逐渐上升的趋势;全省耦合协调度高低分布格局较为稳定,虽然各地市发展存在分级,但地区发展差异有减小的趋势。 展开更多
关键词 耦合协调度 时空演变 交通运输 区域经济 生态环境 山东省
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