中国柑橘生产空间变迁及其驱动因素   总被引：1，自引：0，他引：1  

林正雨  陈强  邓良基  李晓  何鹏  廖桂堂  费建波 《热带地理》2021,41(2):374-387

综合运用产业集中度、探索性数据分析（ESDA）、产业重心模型、空间杜宾模型等方法对中国柑橘生产空间演变特征,以及驱动因素进行实证分析。结果显示：1978－2015年中国柑橘生产空间呈现扩张态势,可分为急剧增长期（1978－1991年）、低速增长期（1992－2000年）、稳步增长期（2001－2015年）。中国柑橘生产空间主要集中在西南地区、中南地区、华东地区,具有“北冷南热”的空间结构。柑橘生产空间在省域尺度上具有显著的正向空间自相关特征,呈现显著的地理集聚现象,且集聚呈现先急剧下降,其后再波动上升的变化过程。自2000年起,生产空间重心持续性向西南向迁移,“西移南扩”的迁移趋势明显。中国柑橘生产空间从最初的自然驱动,逐步转向为“自然－社会”驱动。自然资源禀赋决定着中国柑橘生产的基础空间,社会经济因素是柑橘生产空间变迁的重要原因。在市场区位因素中,道路运输、水果消费对柑橘生产空间存在显著的正向效应,路网密度提高,提升了产区的经济区位,居民收入的提高扩大了柑橘消费需求,因此每提高1%,柑橘面积分别增加0.192%和0.107%。在生产要素中,劳动力投入、水利灌溉对柑橘生产空间存在正向效应,每提高1%,柑橘面积分别增加0.934%和0.094%。在社会经济因素中,非农就业机会引起的农村劳动力流失,对柑橘生产空间存在强烈的负向效应,每提高1%,柑橘面积减少1.365%。科技进步带来的新品种、新技术对柑橘生产空间存在正向效应,每提高1%,柑橘面积增加0.058%。人均粮食占有量的直接效应为负向效应,间接效应为正向效应,意味着在分配有限土地资源的博弈中,本地土地首先要满足粮食安全,因此抑制柑橘面积增加。而邻近地区人均粮食占有量的提高,通过粮食流通能够满足本地粮食安全,促进柑橘面积增加。  相似文献   

洞庭湖流域各季节旱涝及其与大气环流和关键区海温的关系     

刘仲藜  章新平  黎祖贤  贺新光  关华德 《热带地理》2021,41(5):987-999

利用逐月降水数据和NCEP/NCAR再分析数据,分析了洞庭湖流域春、夏、秋季57年来旱涝异常的年际变化以及典型旱涝异常年份的全球海温分布形势,并利用降尺度和趋势分析方法探究气象因子对ENSO和关键区海温的响应,以加强对流域旱涝前期影响因素的认识。结果表明：1）流域在春、秋季旱涝变化趋势不明显,在夏季较明显地变湿。2）前期冬、夏季ENSO事件分别对流域春、秋季旱涝产生显著影响,而与夏季呈不显著的统计特征。3）在消除前期ENSO信号后,阿留申群岛附近海域（S3）、澳大利亚东部海域（S4）海温和印度洋偶极子（Indian Ocean Dipole, IOD）现象仍分别为春、夏、秋季与流域旱涝有密切联系的海温因素。4）S3区SST对流域春季旱涝的影响通过西风带环流实现,S4区SST偏高似乎是东亚夏季风强度偏弱的表现,成熟的IOD现象为流域秋季旱涝的主导因子。  相似文献   

基于PPT战略的广东省乐昌市生态旅游扶贫模式探讨   总被引：1，自引：0，他引：1  

何继红  孙冰  施招婉  罗水兴  王旭  陈雷  熊鹰  林军  裴男才 《热带地理》2021,41(3):645-655

以贫困人口受益为出发点,基于有利于贫困人口发展的旅游（Pro-Poor Tourism, PPT）战略,以广东省乐昌市为例,开展适用于中国南方林区生态旅游扶贫开发的发展模式和旅游扶贫产业的发展路径研究。结果表明：1）政府部门、旅游企业、乡村社区和非营利社会组织都应在提升贫困人口参与度、减轻贫困和生态保护方面承担责任,具体为：政府部门应主导搭建平台和监管落实,旅游企业合理利用生态资源,乡村社区和非营利社会组织相互支持并协助以推进拟定的旅游扶贫发展模式;2）针对乐昌市“生态林木、高山名茶、特色蔬果”等3种特有生态资源,提出以“茶、林、蔬果”三大特色农林资源为抓手的生态旅游发展方式,并提炼出三条适用于乐昌市的产业发展路径,具体为：“休闲农业+特色林果产业+旅游电商产业”“林下休闲业+林下经济产业+林产品初加工”和“森林生态旅游+特色林业种植+自然生态教育”。基于PPT战略,旅游扶贫开发需协调好政府部门、旅游企业、乡村社区和非营利社会组织的关系,只有这四大参与主体共同兼顾生态旅游扶贫开发中的经济、社会和环境效益,才能最终实现PPT战略的经济发展、贫困社区发展、贫困人口与生态可持续发展这三大层次目标。  相似文献   

21世纪以来俄罗斯人口增长与空间分布格局变化     

初楠臣  张平宇  吴相利  李鹤  杨奇峰 《世界地理研究》2021,30(6):1115-1126

在“一带一路”与“中蒙俄经济走廊”倡议的背景下,利用人口增减变化率、人口重心、人口密度变化率、人口地理集中度、人口商度等研究21世纪以来俄罗斯的人口增长与空间分布格局变化。结果表明：（1）21世纪以来,俄罗斯人口经历了先降后增的变化过程;中央区的人口显著上升,伏尔加、西伯利亚与远东区均呈下降趋势;莫斯科、圣彼得堡、乌拉尔区、北高加索区南端的联邦主体人口快速增加,西伯利亚区多数联邦主体人口缓慢增加,远东东部、莫斯科外围地域、伏尔加区多数联邦主体的人口缓慢减少,西北区北端联邦主体的人口急剧减少。（2）俄人口空间分布格局变化主要受地区间人口迁移流动的影响。空间上,俄人口重心不断朝西北向迁移,莫斯科市与圣彼得堡市的人口密度快速增加,远东与东西伯利亚区的人口密度缓慢降低,强化了俄人口分界线——“圣彼得堡-图瓦线”。以“圣图线”为界,俄“西密东疏”“欧洲密、亚洲疏”的格局短期不会改变,整体呈“一横、四纵、两团”及若干区域人口集团的空间结构。  相似文献   

Plate convergence in the Indo-Pacific region     

Sun  Weidong  Zhang  Lipeng  Liao  Renqiang  Sun  Saijun  Li  Congying  Liu  He 《中国海洋湖沼学报》2020,38(4):1008-1017

The Indo-Pacific convergence region is the best target to solve the teo remaining challenge s of the plate tectonics theory,i.e.,subduction initiation and the driving force of plate tectonics.Recent studies proposed that the Izu-Bonin subduction initiation belongs to spontaneous initiation,which implies that it started from extension,followed by low angle subduction.Numerical geodynamic modeling suggests that the initiation of plate subduction likely occurred along a transform fault,which put the young spreading ridge in direct contact with old oceanic crust.This,however,does not explain the simultaneous subduction initiation in the west Pacific region in the Cenozoic.Namely,the subduction initiations in the Izu-BoninMariana,the Aleutian,and the Tonga-Kermadec trenches are associated with oceanic crusts of different ages,yet they occurred at roughly the same time,suggesting that they were all triggered by a maj or change in the Pacific plate.Moreover,low angle subduction induces compression rather than extension,which requires external compression forces.Given that the famous Hawaiian-Emperor bending occurred roughly at the same time with the onset of westward subductions in the west Pacific,we propose that these Cenozoic subductions were initiated by the steering of the Pacific plate,which are classified as induced initiation.Induced subduction initiation usually occurs in young ocean basins,forming single-track subduction.The closure s of Neo-Tethys Oceans were likely triggered by plume s in the south,forming northward subductions.Interestingly,the Indian plate kept on moving northward more than 50 Ma after the collision between the Indian and Eurasian continents and the break-off of the subducted oceanic slab attached to it.This strongly suggests that slab pull is not the main driving force of plate tectonics,whereas slab sliding is.  相似文献   

高精准度智能导航数据产品质量评价系统构建与示范     

黄鹤  邱冬炜  王柳 《北京测绘》2017,(3)

本文针对高精度智能导航地图数据产品的质量控制及评价检测率先开展技术研究,提出了针对车道及智能导航地图的精度评价方法,建立了理论模型和评估体系;研制了对公路要素数据分类分级精度验证模型和方法,解决了HAD和ADAS数据空间绝对精度和相对精度检测的难题;研发了高精度智能导航数据评价系统软件,实现了程序化、标准化和批量化。  相似文献   

Characteristics of systematic errors in the BDS Hatch–Melbourne–Wübbena combination and its influence on wide-lane ambiguity resolution     

Zhang  Xiaohong  He  Xiyang  Liu  Wanke 《GPS Solutions》2017,21(1):265-277

GPS Solutions - The Hatch–Melbourne–Wübbena (HMW) combination is a geometry-free and ionospheric-free (first-order) function that has been widely used for cycle slip detection and...  相似文献   

Multi‐scale approach to mining significant spatial co‐location patterns          下载免费PDF全文

Min Deng  Zhanjun He  Qiliang Liu  Jiannan Cai  Jianbo Tang 《Transactions in GIS》2017,21(5):1023-1039

Spatial co‐location pattern mining aims to discover a collection of Boolean spatial features, which are frequently located in close geographic proximity to each other. Existing methods for identifying spatial co‐location patterns usually require users to specify two thresholds, i.e. the prevalence threshold for measuring the prevalence of candidate co‐location patterns and distance threshold to search the spatial co‐location patterns. However, these two thresholds are difficult to determine in practice, and improper thresholds may lead to the misidentification of useful patterns and the incorrect reporting of meaningless patterns. The multi‐scale approach proposed in this study overcomes this limitation. Initially, the prevalence of candidate co‐location patterns is measured statistically by using a significance test, and a non‐parametric model is developed to construct the null distribution of features with the consideration of spatial auto‐correlation. Next, the spatial co‐location patterns are explored at multi‐scales instead of single scale (or distance threshold) discovery. The validity of the co‐location patterns is evaluated based on the concept of lifetime. Experiments on both synthetic and ecological datasets show that spatial co‐location patterns are discovered correctly and completely by using the proposed method; on the other hand, the subjectivity in discovery of spatial co‐location patterns is reduced significantly.  相似文献   

Housing differentiation and housing poverty in Chinese low-income urban neighborhoods under the confluence of State-market forces     

Shenjing He  Lin Liu  Gangbin Yang  Fenglong Wang 《Urban geography》2017,38(5):729-751

ABSTRACT

Based on a large-scale household survey conducted in six large Chinese cities, this study is among the first attempts to juxtapose factors related to institution, market, and demography to examine the complex patterns and mechanisms of housing differentiation and housing poverty in low-income neighborhoods, which are conventionally conceived as homogenous substandard settlements. Results of Theil indices and multivariate regression models convey several interesting findings. First, the forces of the market and the State have projected different impacts on various aspects of housing status. Institutional factors had significant impacts on some costly and durable housing indicators such as housing tenure and housing area, while market forces have swiftly transformed the most malleable aspects of housing conditions, such as housing facilities, and will eventually replace some institutional legacies. Second, within-group housing differentiation is more palpable than between-group housing differentiation, suggesting that low-income neighborhoods in large Chinese cities are fluid and heterogeneous. Third, different institutional elements have different impacts on housing poverty. The well-functioning market remuneration system helps reduce the risk of housing poverty, yet working poor remains a severe problem. These findings can inform policies promoting social mix and housing affordability.  相似文献   

民族文化资源的类型特征及成因分析——以格萨尔（果洛）文化生态保护实验区为例   总被引：2，自引：1，他引：1  

朱鹤  刘家明  桑子文  魏文栋  魏宗财 《地理学报》2017,72(6):1118-1132

由人类非物质文化遗产《格萨（斯）尔》史诗派生出的格萨尔文化是青藏高原地区独特的区域文化形态。文化资源是文化的载体和展示形式,具有价值性和不可替代性。研究格萨尔文化资源的分类、空间分布及成因对于探讨青藏高原地区人地关系,保护人类非物质遗产有非常重要的意义。果洛藏族自治州是格萨尔文化资源最为富集的区域,并于2014年被授予格萨尔文化生态保护实验区。本文首先对格萨尔文化资源进行界定和分类,并以果洛为例,探讨格萨尔文化资源的空间分布特征及与自然地理条件（高程、水源、坡度、坡向、可达性）的关系,并分析影响文化资源分布的原因,得出以下结论：① 格萨尔文化资源可以分为4大类,11个亚类和60个子类,果洛的格萨尔文化资源覆盖全部类型,共1189个;② 果洛格萨尔文化资源空间分布具有聚集性,其中A类文化人（团体）类集聚程度最高,并通过最近邻分析和密度分析对各类文化资源的集聚空间进行识别;③ 格萨尔文化资源的空间分布与自然地理条件有关,多位于海拔相对较低、距水源地较近的位置,不同类型的文化资源分布对坡度、坡向和可达性的关系不同。  相似文献