Holocene sea level trend on the west coast of Bohai Bay,China: reanalysis and standardization

Using 110 newly revised Holocene sea level indicators categorized into three types, sediments (67), shelly cheniers (27) and oyster reefs (16), this paper firstly provides a Holocene relative sea level curve, based on multiple approaches of litho- and biostratigraphies and sedimentary faces analysis, for the west coast of Bohai Bay, China. Following considerations, including indicative meaning, the paleo tidal pattern and range and conversion from mean tidal level to mean sea level, an apparent relative mean sea level (RMSL) curve was further reconstructed. After systematical calibration using CALIB, those of the 48 reworked samples were further corrected for the residence-time effect. Similarly, the younger ages for another 35 samples were chosen at the subsample level. These result in a younger-oriented shift for about 0.5 ka. Three local spatial factors, including neotectonic subsidence (average rate about 0.1 mm/a), self-compaction of unconsolidated sediments (between a few decimeters to about 6 m) and subsidence due to groundwater withdrawal (between a few centimeters to about 2.5 m), were quantitatively corrected. Finally, the amended RMSL curve after eliminating all these local temporo-spatial factors is very likely to show non-existence of mid-Holocene highstand and imply potential influences of both ice-volume equivalent sea level and regional glacial isostatic adjustment. Although it is still unable to divide both global and regional factors, the slowdown of sea level rise, in 7.5–6.8 ka with a maximum height less than +1 m, may constrain the model effort in the near future.     

Tibetan Lake Expansion from a Pastoral Perspective: Local Observations and Coping Strategies for a Changing Environment

Global climate change is causing the majority of large lakes on the Tibetan Plateau to expand. While these rising lake levels and their causes have been investigated by hydrologists and glaciologists, their impacts on local pastoral communities have mostly been ignored. Our interviews with pastoralists in central Tibet reveal their observations and beliefs about Lake Serling’s expansion, as well as how its effects are interacting with current rangeland management policies. Interviewees reported that the most negative effects on their livelihoods have been reduced livestock populations and productivity due to the inundation of high-quality pastures by saline lake water. However, pastoralists’ collective efforts based on traditional values and norms of sharing, assistance, and reciprocity have helped them cope with these climate change impacts. These local, traditional coping strategies are particularly worthy of attention now, given that the transformation of traditional pastoralism is a goal of current government development initiatives.     

中国地方政府财政赤字率的时空演变——地理监视的应用

运用重心模型、时空跃迁和地理监视揭示了中国地市财政赤字率的时空演变规律与空间相互作用。① 赤字率重心西移,地域不均衡。② 赤字率分布具有路径依赖和空间溢出效应。③ 经济越落后赤字风险越高,赤字冷点区集中于沿海且消退;热点区东扩且风险上升。④ 赤字累积风险顺地势阶梯递减。⑤ 广大中东部地市为非预警区,继续积极财政政策,但支出需偏向社会福利,依靠内需拉动经济增长;预警区多为中西部工业城市,应增强内生动力以实现财政与经济长期协调发展;调控区集中于青藏高原及边缘,中央应加大扶持民生,减轻地方压力。     

西方教育地理学研究评述与本土反思

近20 a来,西方教育地理学受马克思主义地理学以及社会文化地理学思想的影响,重新审视教育空间与社会结构的关联,从多维度进一步认识教育空间建构过程中的政治经济与社会文化机制。对西方教育地理学的产生和发展演变进行分析,并尝试从政治经济和社会文化两大视角,总结和归纳当前西方教育地理学研究的主要成果和内容。教育地理学是一门新兴而又发展迅猛的人文地理学分支,但该学科的理论和实证发展尚处于以西方为主导的阶段,强势的西方话语体系还未充分涉及和理解非西方国家背景下的教育现象。当前是非西方国家建构自身教育地理学理论特色,并与西方教育地理学研究展开理论和实践对话的重要机遇和窗口。中国拥有世界规模最大的教育群体,当前社会经济发展的转型和人口结构的改变也进一步塑造了教育空间的多样性和特殊性。总之,加深教育与空间关系的研究,增强教育地理学研究的中西对话,构建中国化的教育地理学研究体系,使教育空间成为考察中国社会经济转型的重要视角,是中国教育地理学研究未来应努力的方向。     

基于多源数据的武汉市多中心空间结构识别

研究城市不同要素空间集聚水平与层级差异、明确城市各职能中心分布,对城市多中心空间结构的发展引导和规划调控具有重要意义。论文分别采用兴趣点(points of interest, POI)、夜间灯光和路网3种数据,利用局部等值线树算法,识别武汉市多中心空间结构。研究表明：① 武汉不同城市要素的总体集聚水平不均衡,其中在汉阳集聚水平较低,在汉口和武昌集聚水平较高,特别是二环以内区域;② 武汉中央活动区发展比较均衡,内部各城市要素高度集聚,随着向外扩展,部分城市要素易于在局部集聚形成城市中心;③ 结合武汉圈层发展布局,城市中心沿环线的“商-住-工”职能分布模式逐步确立,其中内环以及二环区域已形成稳定的商服中心;二环附近综合组团内部出现了较具代表性的居住中心;三环外的沌口和武钢主导发展工业,是典型的工业中心。     

基于DEM的对称13点局部窗口坡度算法分析

局部曲面拟合法是基于DEM的计算坡度的常用方法之一,采用不同的拟合曲面和局部移动窗口将得到不同精度的计算模型,探索不同的局部窗口类型可以丰富局部曲面拟合法在数字地形分析中的应用。本文考虑不同距离临近点的高程信息,基于3×3局部窗口提出了一种由两种不同倍率、与主轴(x轴、y轴)呈45°夹角的格网点构成的新窗口——对称13点局部窗口,推导了三阶曲面拟合该窗口的坡度计算公式,并利用典型数学曲面对该模型的计算精度进行了分析。研究分析认为,相对于现有的坡度计算模型,三阶曲面拟合对称13点窗口模型能显著地提高坡度计算精度,但对误差的平滑能力较差,适用于高精度DEM。本文的研究扩展了曲面拟合法在数字地形分析中的应用。     

A visualization approach for discovering colocation patterns

Colocation mining is one of the major spatial data mining tasks. When discovering colocation patterns, spatial statistics or data mining approaches are commonly used. Colocation mining results are typically presented in a textual form and do not provide any spatial information; thus, the results lack an intuitive approach to obtain cognition of colocation rules. Here, we propose a visualization approach to discover colocation patterns for two independent point distributions and generate visual results. This approach makes use of the ability of human color perception. For two geographic features, our approach first generates density surfaces of the input features and then visualizes the density surfaces using a red or green light with different intensities. Then, based on the law of additive color mixing, our approach mixes the colors of the two density surfaces to generate a colocation rule map. The visualization approach can also provide local details of colocation and be used for local colocation analysis. Users can detect colocation patterns and their distribution from the colocation rule maps. We use both synthetic data and real data to test the performance of our approach.     

A response to ‘A comment on geographically weighted regression with parameter-specific distance metrics’

In this article, we respond to ‘A comment on geographically weighted regression with parameter-specific distance metrics’ by Oshan et al. (2019), published in this journal, where several concerns on the parameter-specific distance metric geographically weighted regression (PSDM GWR) technique are raised. In doing so, we review the developmental timeline of the multiscale geographically weighed regression modelling framework with related and equivalent models, including flexible bandwidth GWR, conditional GWR and PSDM GWR. In our response, we have tried to answer all the concerns raised in terms of applicability, veracity, interpretability and computational efficiency of the PSDM GWR model.     

本土产业发展视角下的乡村地方性重构——基于阳美玉器产业的文化经济地理分析

以广东揭阳的玉器生产专业村阳美村为例,从文化经济地理学视角解读本土产业发展中地方性的嵌入与重构。研究发现：本土产业在地方性多方要素的驱动与支撑下产生,在多重尺度政治经济过程作用与地方主体的响应下发展。地方性是本土产业产生并建立对外功能联系的初始条件,也是主体响应结构变动所做战略选择和地方营销的依托。在地方性嵌入产业发展的同时,生产、生活和宗教等地方活动被强化了与玉器生产相关的功能和意义,民居、街巷、宗祠等空间形制因传统功能被挤压而出现重塑。地方活动与景观的变化并未弱化地方意义,村民的地方依赖和依恋因本土产业提供了更好的发展机会与荣誉感而增强。     

多星中天时角法精密测定天文方位角

在高精度天文方位角测定方法中,北极星任意时角法只适用于北半球中纬度地区,子午星对法则受限于选星配对条件.提出可适用于全球地区的多星中天时角法,观测多颗任意中天位置的南星和北星,通过线性回归模型修正测站经度误差和计时误差对方位角解算的影响.该方法只需已知测站的概略位置,对观测天体的中天位置没有限制.实测数据表明,与北极星任意时角法相比,在相同精度指标要求下,观测量可以减少一半.