基于城镇用地和最小时间成本的城市影响区划分及其人口分析

以宁蒙沿黄地带为案例,基于城镇用地和最小交通时间成本划分城市影响区,分区统计影响区人口,将其与城市行政区非农人口的增速差进行统计分析。结果表明：基于城镇用地和最小交通时间成本的城市影响区划分边界更接近于行政区界;考虑城镇用地后大城市影响区扩展,考虑最小交通时间成本后小城市影响区相对扩展;以东胜区-伊旗为中心的地区非农人口增速始终显著高于潜在服务人口增速,这类城市应增强对周边县的扩散作用;以大武口-惠农区为中心的地区非农人口增速始终显著低于潜在服务人口增速,这类城市应加速产业与非农人口集聚。     

基于农户调研的中国农村居民点空心化程度研究

基于中国范围的乡村人居环境调研数据,分析了中国农村宅基地空心现象。结果表明：① 中国农村宅基地空心化严重,93.5%的调研村庄有空心化现象,平均空心化率达到10.2%。② 省域农村宅基地空心化差异明显,其中华北、华东、华中地区普遍较高;③ 多种因素导致农村宅基地空心化,认为是“外出务工”、“户口迁移”、“房屋年久失修”及“一户多宅” 的受访者分别占39.94%,19.51%,25.73%和14.82%。④ 中国农村空心化宅基地再利用潜力巨大,但再利用难度大,需要从改革城乡二元体制和乡村空间重构的角度进行空心村整治。     

旅游引导的新型农村城镇化研究——以丹霞山瑶塘村与断石村为例

采用质性研究方法,揭示1980~2014年间丹霞山瑶塘村和断石村在旅游引导下实现农村城镇化的过程特征和机制。研究发现,在旅游驱动下,地方政府、农村社区、外来力量等多元主体共同作用下两村逐步实现了“以人为核心”的新型农村城镇化;地方政府的有效管理和资金扶持,有力保障了农村公共设施建设和旅游企业发展,防止“公地悲剧”和“虚假城镇化”现象发生;农村社区以土地、资金和劳动力等要素主动参与旅游经营和社区建设,实现了产业、就业和生活方式的非农化,是农村城镇化的主导力量;以外来资本、旅游移民和旅游者等为主的外来力量为农村城镇化提供了资金、劳动力、文化和信息等支持,其作用随着旅游市场规模的扩大而逐步加大。研究认为,当前旅游驱动型农村城镇化并非传统意义上农民空间、职业和身份都发生转化的城镇化,而是农民通过参与旅游就地转变生产和生活方式的内生型城镇化,未来可通过“村改居”方式逐步向区域城镇化转换。     

云南省城镇上山压力指标体系测算与分析

在提出城镇上山压力概念的同时构建了城镇上山压力指标体系,并进一步运用层次分析法、德尔菲法和综合模糊评价法测算和分析了2020年云南各州(市)的压力等级。研究结果表明:1由于耕地资源、人口、经济发展水平、农村社会发展不同,云南省城镇上山压力存在明显的空间非均衡性;2将云南城镇上山压力分为4个等级:Ⅰ等超高压主要位于滇中中部地区,Ⅱ等高压主要分布于滇中西部和东部、滇东南西部以及滇西南南部,Ⅲ等中压主要分布于滇中中部、滇西南大部分地区、滇西北的东部地区和滇东北北部,Ⅳ等低压主要分布于滇东南的东部和滇西北的西北部;3通过差异化的上山政策可以缩小城镇上山压力的非均衡性差距,云南省未来城镇上山的重点区域主要集中在滇中中东部、滇东南西部以及滇西南南部。     

Vertical differentiation in urban space: A case of Aizawl city

Cities are characterized by sociospatial differentiation. Intra‐urban inequality is found in cities across the world. Cities in the ‘peripheral south’ have been neglected in spite of their significant role in theoretical formulations and generalizations. The present paper attempts to argue that sociospatial differentiation is an inherent characteristic of cities, although the spatial form of inequality may vary depending on the specific culture and physical geography of the area. In the remote city of Aizawl in the eastern Himalayan region of India, multi‐storey buildings are cohabitated by higher and lower income classes ‐ the former were found at the top floors and the latter at the bottom floors. The vertical arrangement of income classes within a single building is seen as an adjustment strategy of the increasingly urbanized ‘tribal’ society in the hilly terrain of the city.     

国产资源三号测绘卫星DSM数据质量评价--以高海拔山区为例

为了评价国产资源三号测绘卫星DSM数据精度,在顾及地貌类型的情况下,以涵盖平原、台地、丘陵等地貌的高海拔山区为研究案例,并以1∶1万实测地形图DEM为假定真值,以90m分辨率SRTM DEM为评价参照,从高程精度和地形描述精度两个方面,对15m分辨率ZY-3DSM进行精度评价分析。研究结果表明:ZY-3DSM高程精度优于SRTM DEM,前者高程中误差仅为后者的1/6;就地形描述精度来讲,ZY-3DSM与SRTM DEM相比,其地形描述精度更接近理论值,前者RMS Et实际值仅为理论值0.99倍,而后者的实际值却是理论值5.13倍。由此看来,ZY-3DSM数据精度整体上高于SRTM DEM。     

中国海域及邻区含油气盆地生物礁的对比研究

本文阐述了中国海域及邻区含油气盆地生物礁形成环境,分布、时代、与发育演化特征,进而提出三种成礁模式。指出在东海,渤海湾盆地存在发现礁油气田的可能性及工作建议。     

Numerical simulation of larval shrimp dispersion in the Northern Region of the Gulf of California

The trajectories of shrimp larvae in the northern part of the Gulf of California were studied from a Lagrangian point of view using a three-dimensional numerical model. The advection of particles was carried out over fortnightly periods starting at spring and neap tides. The northernmost region of the gulf has important shrimp fisheries and nursery areas have been located off the coast of Baja California at San Felipe (SF) and off the Sonora coast at Santa Clara (SC). Though the reproduction zone is believed to be south of these nursery areas, there is much that remains unknown about the zone and the routes used by shrimps to reach these areas. Passive and active simulations of shrimp larvae drift were carried out in order to study the possible areas of shrimp spawning and their migratory routes. The active migration schemes were based on assumptions that the larvae can be advected only: (1) during the day, (2) at night or (3) when the currents flow in the northward direction toward the nursery areas. It was found that the larvae in Santa Clara and San Felipe came from different production zones. No differences were found between the spring and neap tide scenarios except for the diurnal migration experiments. The distance traveled by shrimp larvae was always less than 40–50 km, except in the cases when the larvae selected the appropriate direction to the nursery areas when the larvae travel 140 km to SC and 95 km to SF.