地方小吃空间扩散格局与模式——基于中国四大知名地方小吃POI数据的研究

以中国四大知名地方小吃门店兴趣点（POI）大数据为主要数据源,基于密度、距离与加权平均中心方法分析地方小吃空间集聚与扩散格局,采用空间自相关、聚类和异常值分析以及热点分析方法研究地方小吃空间集聚关联特征以及空间扩散模式。结果表明：① 地方小吃在不同尺度上的空间扩散格局存在显著差异,东部地区和中西部省会城市是地方小吃的主要集聚地;② 地方小吃的空间集聚表现出自相关特征,邻域扩散、等级扩散和跳跃式扩散等扩散模式相互融合;③ 地方小吃空间扩散的冷热点集聚区分异明显,反映出不同小吃认可群体范围的差异以及中国各地饮食习惯的空间分异;④ 饮食文化扩散与人口迁移扩散具有空间重合性,经济发展水平较高、人口净流入地区对不同饮食文化的包容性较强。     

高中生在线学习问题的案例研究——以“地理高考专题复习”慕课为例

新冠疫情防控时期,我国开展了大规模在线教学的试验,目前亟需对在线教学效果进行总结与反思。本文基于疫情期间“地理高考专题复习”慕课的1.6万多名全样本在线学习日志,利用大数据分析方法,结合访谈调查,证实学生自主化、个性化的在线学习存在着行为参与度低、认知水平浅、情意品质低等问题,并着重分析了问题的主要成因,提出优化在线课程设计与管理、改进在线教学方式、提升师生信息素养等建议。     

绿色金融如何影响中国城市环境污染？——以雾霾污染为例

文章将绿色金融纳入环境规制的分析框架,以2016－2019年中国289个地级以上城市雾霾污染为例,使用空间杜宾模型探讨绿色金融、环境规制、产业结构、技术水平对雾霾治理的影响,侧重分析了绿色金融与其他因素的交互作用。结果表明：绿色金融具有空间溢出效应,本地绿色金融可以降低周边地区雾霾污染;绿色金融能够与环境规制协同互补,以优化产业结构、提升技术水平的方式促成雾霾治理。绿色金融的结构效应弱于环境规制,在中部地区并不显著;绿色金融的技术效应强于环境规制,能够激励不同地区技术创新。文章启示,绿色金融与环境规制能够相互增益,应建立区域间绿色金融合作机制,增强绿色金融的普惠性,助力区域产业转型和污染治理。     

DEM在湖泊水文变化研究中的应用进展

在全球变化背景下,湖泊水文的动态变化不仅是评估和预测气候与环境变化的重要指示剂,同时对社会可持续发展、水资源的开发与利用、生态文明建设等产生重要影响。湖泊水文的动态变化受到湖滨及湖底地形的控制,数字高程模型（DEM）成为湖泊水文研究的重要数据源。随着遥测技术的发展,高分辨率、区域/全球大尺度DEM数据的获取手段快速发展、数据源不断丰富,DEM对推动湖泊水文动态研究进展起到了关键作用。本文首先基于Web of Science平台对DEM在湖泊水文动态研究中的相关文献进行了分析,阐述了该主题现有研究在发文时间、发文数量增减态势、研究区域与热点地区、文献所涉及的DEM数据等方面的特点。接着,围绕着DEM在湖泊水文动态的研究中4个主要方向：湖泊水域变化、湖泊水位变化、湖泊水量变化、湖泊水文灾害情势,重点总结：DEM与其他遥感观测平台、实地观测及模型模拟等多源数据的融合策略,数字地形分析与水文学分析、遥感影像分析等方法的集成策略,以及DEM数据不确定性等对湖泊水文变化研究的影响。最后,本文论述了目前DEM在湖泊水文研究中存在的关键问题,并结合技术发展趋势和研究热点问题,提出了可能的解决路径和未来的研究前景。     

Provenance and Tectonic Implications of Paleozoic Strata in the South Yellow Sea Basin,China–Revealed from the Borehole CSDP-2

Well CSDP-2 is a fully coring deep drilling hole, penetrating the thick Paleozoic marine strata in the South Yellow Sea Basin(SYSB) in the lower Yangtze Block(LYB). Based on the petrological and geochemical analysis of 40 sandstone samples from the core CSDP-2, the provenance and tectonic features of Paleozoic detrital rocks from SYSB are analyzed and systematically delineated in this article. The results show that the Silurian – Carboniferous sandstones are mature sublitharenite, while the Permian sandstones are unstable feldspathic litharenite. The average CIA(chemical index of alteration) is 74.61, which reflects these sediments were derived from source rocks with moderate chemical weathering. The REE(rare earth element) patterns are characterized by LREE enrichment, flat HREE and obviously negative Eu anomaly, which are similar to that of the upper continental crust. Dickinson QFL discrimination results indicate the recycled orogeny provenance. Various diagrams for the discrimination of sedimentary provenance based on major and trace element data show all the sediments were derived predominantly from quartz sedimentary rocks, of which the Permian strata contain more felsic sedimentary rocks. Geochemical data for these detrital rocks suggest they occur at the passive continental margin and island arc settings, and the Permian sandstone presents active continental margin setting.     

地勘基金成果管理系统的设计与开发

本文在分析国内地质资料信息化服务现状的基础上,以地勘基金成果数据为管理对象,搭建了地勘基金成果管理系统,并以贵州省地勘基金成果数据为例,实现了该地区地勘基金项目、整装勘查项目地质数据的有效管理与查询,为地质资料的管理与应用提供了科学的决策支持.     

市县级国土资源信息化统筹推进的实践与探索

本文探讨了在全省范围内通过统一建设的方式,以国土云为核心,抓好顶层设计,统筹规划、统一建设推进基层国土资源信息化建设,对于加快国土资源部门基层信息化应用发展具有重要的参考价值.     

Stable isotopes and trace elements in modern ostracod shells: implications for reconstructing past environments on the Tibetan Plateau,China

Stable isotopes and trace elements in ostracod shells have been used widely in paleolimnological investigations of past lake hydrochemistry and climate because they provide insights into past water balance and solute evolution of lakes. Regional differences in lake characteristics and species-specific element fractionation, however, do not permit generalization of results from other regions or ostracod species to the southern Tibetan Plateau, in part because most common taxa from the southern Tibetan Plateau are endemic to the area. This study evaluated relations between present-day environmental conditions and the geochemical composition of modern ostracod shells from the southern Tibetan Plateau, to assess the suitability of using shell chemistry to infer hydrological conditions. We studied nine lakes and their catchments, located along a west–east transect in the south-central part of the Tibetan Plateau. Stable oxygen and carbon isotope values and trace element concentrations in recent shells from the four most abundant ostracod species (Leucocytherella sinensis, ?Leucocythere dorsotuberosa, Limnocythere inopinata, Tonnacypris gyirongensis) were measured, together with hydrochemical properties of host waters at the time of sampling. Results revealed significant between-species differences in stable isotope fractionation and trace element incorporation into shell calcite. Stable oxygen and carbon isotope values of ostracod shells were correlated significantly with the stable isotope composition of the respective water body \( \left( {\updelta^{18} {\text{O}}_{{{\text{H}}_{ 2} {\text{O}}}} \,{\text{and }}\updelta^{13} {\text{C}}_{{{\text{H}}_{ 2} {\text{O}}}} } \right) \), reflecting salinity and productivity, respectively. Offsets between δ¹⁸O_shell and δ¹³C_shell and inorganic calcite, the latter representing isotopic equilibrium, suggest shell formation of T. gyirongensis during spring melt. L. sinensis reproduces throughout the monsoon season until September and shows several consecutive generations, and L. inopinata molts to the adult stage after the monsoon season in August/September. The influence of pore water δ¹³C was displayed by L. inopinata, suggesting shell calcification within the sediment. Mg/Ca_shell is primarily influenced by water Mg/Ca ratios and salinity and confirms the use of this shell ratio as a proxy for precipitation-evaporation balance and lake level. In addition, Sr/Ca and Ba/Ca can be used to infer changes in salinity, at least in closed-basin lakes with calcite saturation. Observed effects of water Sr/Ca and salinity on Sr/Ca incorporation are biased by the presence of aragonite precipitation in the lakes, which removes bioavailable Sr from the host water, resulting in low Sr/Ca_shell values. Changes in carbonate mineralogy affect the bioavailability of trace elements, a process that should be considered in paleoclimate reconstructions. Oxygen isotopes and Mg/Ca_shell ratios were unaffected by water temperature. Positive correlations among Fe/Ca, Mn/Ca and U/Ca in ostracod shells, and their negative correlation with δ¹³C, which reflects organic matter decay, show the potential to infer changes in redox conditions that can be used to reconstruct past oxygen supply to bottom waters and thus past water-circulation changes within lakes. The intensity of microbial activity, associated with organic matter decomposition, can be inferred from U/Ca ratios in ostracod shells. These findings highlight the value of fossil ostracod records in lake deposits for inferring paleoenvironmental conditions on the southern Tibetan Plateau.     

中国入境旅游的经济增长效应与空间差异性研究

在旅游业与经济增长作用关系分析基础上,探究了旅游溢出理论,将其产生机制归纳为知识溢出、市场溢出和竞争效应3个方面。实证分析中,构建了包括入境旅游、物质资本、人力资本、科技创新和对外开放的分析框架,运用中国大陆31个省域2000~2014年面板数据对入境旅游的经济增长效应进行实证检验。全局分析得出中国入境旅游在邻近省市以集聚与合作为主,邻近省域入境旅游发展对本地经济增长具有辐射带动作用,且这种空间溢出效应大于直接效应;入境旅游业发达的地区,入境旅游的经济增长效应更大。局部分析发现,随着入境旅游的发展,入境旅游的经济增长效应不断强化,中部部分地区提升幅度最大;入境旅游的经济增长效应存在空间差异性,东部沿海地区贡献最大,西北地区相对最小。