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1.
谢花林  李波 《地理研究》2008,27(2):294-304
本文以农牧交错带的典型区域——内蒙古翁牛特旗为例,考虑土地利用变化过程的空间变量,建立了不同土地利用变化过程的logistic回归模型。结果表明:模型中转为耕地的主要解释变量是到农村居民点的距离和农业气候区;转为草地的主要解释变量是到农村居民点的距离、土壤表层有机质含量和到乡镇中心的距离;转为林地的主要解释变量是到农村居民点的距离和海拔;空间异质性和土地利用变化过程的时间变量共同影响着使用logistic回归模型来解释土地利用变化驱动力的能力;通过对草地logistic回归模型的检验,得出空间统计模型能较好地揭示不同土地利用变化过程的主要驱动力及其作用机理。  相似文献   

2.
Quantitative measures of accessibility are increasingly used in land cover change modeling and in assessing human pressure on the environment. In riverine Amazonia the significance of physical accessibility for biodiversity, land use patterns and economic livelihoods is widely acknowledged, but attempts to quantify accessibility in practice have been few in number. In this study we compare different distance- and frequency-based measures of spatial accessibility and develop a quantitative model of accessibility patterns for the north-eastern Peruvian Amazonia where rivers form the core of the transportation network. We model accessibility between the rural areas of the Loreto region and the capital city of Iquitos, using different distance algorithms in a geographic information system, and complement the distance model with information on river boat frequencies and transport capacities. Patterns of accessibility are visualized in terms of potential production zones for different types of agricultural and non-timber forest products.This study demonstrates how results from different accessibility measures vary considerably. The mean Euclidean distance to Iquitos is almost 270 km, the mean network distance nearly 760 km and the mean travel time 70 h. Observed network distances from validation points to Iquitos are on average 1.6 times longer than Euclidean distances, and for the whole study area, the average ratio between modeled network distances and Euclidean distances is 3.1. The correlation between network distances and time distances is very strong, but time distances are relatively shorter along the major channels where boat traffic is considerably faster than along narrow, tightly meandering rivers. Measures of boat frequency and transport capacity show that availability of transport possibilities is highly varying across the region. These measures provide insights into the ’thickness’ of trade, indicating the level of market integration for riverine settlements. We conclude that quantifying accessibility in an environment like Peruvian Amazonia requires measures that take into account the spatial structure and dynamic nature of the riverine transportation network. Time as a unit of distance provides the most relevant measure of accessibility in the Amazonian context, where many human actions and traditional livelihoods are controlled by travel times between the regional core and the hinterland.  相似文献   

3.
北京市土地利用空间格局演化模拟及预测   总被引:5,自引:2,他引:3  
土地利用空间格局的演化模拟可定量地从空间尺度揭示区域土地利用变化的驱动因素,是厘清未来时期内土地变化的重要途径。基于CLUE-S模型,以北京市为研究案例,结合1985、2000和2010年三期土地利用数据,运用Logistic逐步回归方法识别了北京市各种土地利用类型演化的驱动因素,对北京市土地利用空间格局进行模拟。在此基础上,基于北京市社会经济发展、土地利用规划、资源禀赋及生态保护等不同情景,对北京市2020年土地利用空间分布格局进行模拟及预测。结果表明:①不同的时期内,驱动因子对不同土地利用类型的影响呈现差异性,其中交通因素及社会经济因素对土地利用类型的转化率影响较显著,坡度对各个土地利用类型的影响较大。②通过对2010年北京市土地利用变化的模拟结果来看,Kappa指数为87.03%,说明预测结果与实际土地利用情况有较好的一致性。③预测结果显示,北京市的城市发展均表现为继续向外扩展,且以东南、东北为主要扩展方向,但扩张的程度存在差异。  相似文献   

4.
张新长  刘涛  张文江 《热带地理》2005,25(4):351-355
对研究区内不同年份的土地利用图进行叠置等空间信息处理运算,获得3个时段土地利用的空间变化图,将一个网格图层分别与3个时段的土地利用变化图叠加,分析各空间单元的年均变化强度指数,得到土地利用的空间变化结果.然后对年均变化强度指数进行分级统计后得到二级用地类型的土地利用空间变化情况,并结合社会经济因素加以分析,得到研究区3个不同时段的土地利用空间变化趋势.最后对主要二级用地类型的时空结构演变情况进行概括性的分析和评价.  相似文献   

5.
This study is proposed to reconstruct a high-resolution spatial distribution of historical land use pattern with all land use types to overcome low-accuracy and/or the monotonic land use type in current historical land use reconstruction studies. The year of 1820 is set as the temporal section and the administrative area of Jiangsu Province is the study area. Land use types being reconstructed include farmland, residential land (including both urban land and rural residential land), water body, and other land (including forest land, grassland, and unused land). Data sources mainly refer to historical documents, historical geographic research outcomes, contemporary statistics, and natural environmental data. With great considerations over regional natural resources and social and economic conditions, a few theoretical assumptions have been proposed to facilitate the adjustment on prefecture farmland, urban land, and rural residential land. Upholding the idea that the contemporary land use pattern has been inherently in sequence with the historical land use pattern as well as the land use pattern shall be consistent to its accessibility, this study reconstructs the land use pattern in Jiangsu Province in 1820 with 100 m*100 m grids based on accessibility analysis and comprehensive evaluation. The outcome has been tested as valid by regionalization and correlation analysis. The resulted spatial distribution shows that back in 1820 in Jiangsu Province: (1) farmland, urban land, rural residential land, water body, and other land take about 48.49%, 4.46%, 0.16%, 15.03%, and 31.86% of the total land area respectively; (2) the land use pattern features high proportion of land in farming while low-proportion land in non-farming uses while population, topography, and the density of water body lead to great spatial variations; and (3) the reconstruction methodology has been tested as reasonable based on significant positive correlations between 1820 data and 1985 for both farmland and rural residential land at the prefecture level.  相似文献   

6.
乡镇土地利用总体规划对农村居民出行可达性的影响研究   总被引:4,自引:0,他引:4  
可达性是反映区域土地利用状况、居民生活质量和社会公平性的重要指标。提出适用于乡镇土地利用总体规划的农村居民出行可达性分析方法以及GIS支持的实现思路,以浙江省临安市太湖源镇土地利用总体规划方案为例,分析规划前后农村居民出行的可达性情况,并评价规划对农村居民出行可达性的影响。  相似文献   

7.
黄土高原地区乡村性空间特征及其与可达性格局关系   总被引:1,自引:0,他引:1  
吕敏娟  曹小曙 《地理科学》2020,40(2):248-260
在乡村转型重构的关键时期以及城乡融合背景下,可达性作为驱动乡村地域特征改变的直接媒介,对乡村减贫及可持续发展产生重要影响。以县域为基本空间单元,构建了刻画乡村性和可达性的指标体系,定量测度了1990年、2000年、2010年、2015年黄土高原地区243个县域乡村性与可达性指数,探索黄土高原地区县域乡村性和可达性的时空演变特征,采用探索性空间数据方法,引入空间计量经济模型,对乡村性与可达性的集聚特征及关系进行计量分析。结果显示:研究区乡村性整体呈减弱态势、差异不断增大,呈现“西高东低”分布格局;可达性整体呈增强趋势、差异不断缩小,“东高西低”的分布格局基本不变。乡村性与可达性空间分布均呈较强的正空间自相关,以“榆林-庆阳”一线为界分布,但集聚态势总体不断减弱;其次,可达性的提升对乡村性呈负向影响且波动增强,低可达性-高乡村性类型主要分布在西北的青海、甘肃、宁夏境内,高可达性-低乡村性类型主要分布在东部经济发展水平较高的地级市周边县市。乡村性的空间溢出效应显著,表现出显著的空间滞后和空间误差溢出效应,区域乡村性会受到周边地区乡村性的显著影响;可达性的提升会使得乡村人口变化率、一产产值比重降低;使农业劳动生产率、农村人均纯收入、农业土地生产率提高,且可达性对农业土地生产率的影响最大,而对农村居民人均纯收入的影响提升最大。  相似文献   

8.
闽东北沿海罗源县土地利用空间分布格局的 多尺度分析   总被引:4,自引:0,他引:4  
在不同的空间尺度上,制约土地利用空间分布的影响因子及其影响程度并不相同,因此区域空间分布格局 分析应优先考虑制约空间分布的影响因子识别及其影响程度的尺度依赖性的研究。本文以闽东沿海的罗源县为研 究区域,采样统计方法与GIS 技术,选取20 个候选影响因子,研究了该县主要土地利用空间分布格局的影响因子 及其空间尺度相关性。研究表明模型的解释能力、影响因子及其影响系数均会随研究尺度发生不同程度的变化,回 归模型的解释能力以及主要影响因子的制约程度总体上均随研究尺度增大呈增强趋势。除受坡度、海拔高程等地 形条件的严格制约外,罗源县主要地类均在一定程度上受到人口因素以及若干可达性因素的影响。  相似文献   

9.
This study is proposed to reconstruct a high-resolution spatial distribution of historical land use pattern with all land use types to overcome low-accuracy and/or the monotonic land use type in current historical land use reconstruction studies. The year of 1820 is set as the temporal section and the administrative area of Jiangsu Province is the study area. Land use types being reconstructed include farmland, residential land(including both urban land and rural residential land), water body, and other land(including forest land, grassland, and unused land). Data sources mainly refer to historical documents, historical geographic research outcomes, contemporary statistics, and natural environmental data. With great considerations over regional natural resources and social and economic conditions, a few theoretical assumptions have been proposed to facilitate the adjustment on prefecture farmland, urban land, and rural residential land. Upholding the idea that the contemporary land use pattern has been inherently in sequence with the historical land use pattern as well as the land use pattern shall be consistent to its accessibility, this study reconstructs the land use pattern in Jiangsu Province in 1820 with 100 m*100 m grids based on accessibility analysis and comprehensive evaluation. The outcome has been tested as valid by regionalization and correlation analysis. The resulted spatial distribution shows that back in 1820 in Jiangsu Province:(1) farmland, urban land, rural residential land, water body, and other land take about 48.49%, 4.46%, 0.16%, 15.03%, and 31.86% of the total land area respectively;(2) the land use pattern features high proportion of land in farming while low-proportion land in non-farming uses while population, topography, and the density of water body lead to great spatial variations; and(3) the reconstruction methodology has been tested as reasonable based on significant positive correlations between 1820 data and 1985 for both farmland and rural residential land at the prefecture level.  相似文献   

10.
Geographic variations in spatial accessibility to public resources, such as health care services, raise important questions about the efficiencies and inequities of the processes that determine where these services are located. Spatial accessibility can be measured many different ways, but many of methods in use today involve some measure of travel cost (in time or distance). In this study we explore a simple methodological question: how much are models of spatial accessibility influenced by the precise metric of travel cost? We address this question by comparing spatial accessibility to primary care physicians for two different methods of calculating travel cost (in time) on a street network: free-flow travel time and congested with turn penalties travel time—which augments free-flow travel times with the burden of traffic congestion and traffic intersection controls. We consider the effect of these two metrics of travel cost on a gravity-based measure of spatial accessibility to primary health care services in Edmonton, Alberta, Canada. Our results suggest that while travel times between locations of demand and locations of primary care providers greatly differ based on how travel cost is calculated, the gravity-based measure of spatial accessibility provides similar information for both travel cost metrics. Using congested with turn penalties travel time can be an onerous addition to the analysis of spatial accessibility, and is more useful for measuring absolute travel time rather than modeling relative spatial accessibility.  相似文献   

11.
土地利用/ 土地覆被变化(LUCC) 是当前研究全球变化的重要内容, 而区域土地利用 格局模拟是LUCC 研究的核心内容之一。以张家界市永定区为研究单元, 根据由2005 年土地 利用现状图和数字高程模型数据源得到的土地利用、地形、河流以及道路等空间数据, 对区 域土地利用类型空间格局的空间自相关性特征进行了建模研究, 并通过在传统Logistic 模型 中引入描述空间自相关性的成份, 实现了能够考虑自相关性因素的回归分析模型 (AutoLogistic 模型), 同时应用该模型对区域土地利用格局进行了模拟和分析。结果显示, 通 过与没有考虑空间自相关性的回归模型(传统Logistic 模型) 相比较, 该模型显示了更好的拟 合优度和更高的拟合准确率(耕地、林地、建设用地及未利用地的ROC 值分别从0.851、 0.913、0.877 和0.852 提高到0.893、0.940、0.907 和0.863)。研究结果说明了基于 AutoLogistic 方法的土地利用格局的相关性建模在一定意义上是合理的。同时研究结果也可以 为永定区及其相似地区的土地利用规划决策提供更为科学的依据。  相似文献   

12.
改革开放以来,珠三角地区的工业迅速发展,村镇土地利用快速非农化,其中以东莞、中山、佛山3市最为典型。论文以3市为案例,探讨2010年来珠三角村镇建成区空间型态。研究数据主要包括广东省2015年土地利用现状数据和2009—2015年间3市的土地利用数据。首先,通过斑块密度、空间离散度、空间均匀度、平均斑块面积、分形维数、景观破碎度、缓冲区分析、Moran's I指数这8个指标,分析建设用地的空间形态特征。其次,分析工业用地与非工业建设用地、建设用地与交通道路的空间分布关系,比较并总结3市的村镇建成区空间类型。最后,基于灰色关联分析法,探讨影响空间类型的产业发展因素。研究发现,东莞村镇建设用地呈现高度破碎均匀分布型,佛山呈现团状离散型,中山介于二者之间,为中度碎化分散型;3市的产业发展能较大程度上影响其形成不同的建成区空间型态。未来,基于产业经济作为村镇建成区空间特征变化的主因,珠三角可以结合粤港澳大湾区规划建设,通过调整产业结构、布局以及交通和土地利用,优化村镇空间布局。  相似文献   

13.
This paper examines the relationship between different street centralities and land-use types in Stockholm. Major centrality measures of closeness, betweenness, and straightness are calculated at both global and local levels in both the primary and dual representations of the urban street network. Adaptive kernel density estimation is adopted to transform all unevenly distributed datasets to one continuous raster framework for further analysis. After computing statistical and spatial distribution of each centrality and land-use density map, we find that the density of each street centrality is highly correlated with one type of land use. Results imply that various centralities representing street properties from different aspects can capture the land development patterns of different land-use types by reflecting human activities, and are consequently important indicators to describe urban structure.  相似文献   

14.
公共医疗设施配置合理与否影响城乡居民健康和福祉,科学客观测算乡村地区公共医疗设施公平可达性具有重要意义。乡村地区人口规模较小且分散居住,居民就医行为有别于城市居民,2SFCA或3SFCA方法难以客观揭示乡村地区人口分布规律和就医出行特征,导致评估乡村地区医疗设施可达性时效果不佳。论文根据海口市乡村居民就医出行规律选择距离衰减函数,格网化研究区形成人口需求点,考虑不同等级医疗机构对居民就医的吸引,改进了3SFCA算法,建立乡村地区公共医疗设施可达性与空间公平性评估方法体系,并以海口市为案例进行实证分析。结果表明:① 基于改进3SFCA法建立的可达性评价模型可以获得更精准客观的评价结果;② 海口市乡村地区公共医疗设施可达性整体较差且空间分异明显,高值区分布在东部的三江、云龙及甲子镇,低值区主要集中在研究区西部;③ 海口市乡村地区公共医疗设施配置的公平性不佳,少量的高和较高公平等级区域均位于中低人口密度区,而低和极低公平等级区域覆盖了广大的高人口密度区,医疗资源配置的公平性亟需改善。  相似文献   

15.
胡瑞山  董锁成  胡浩 《地理科学进展》2012,31(12):1600-1607
精确评价医疗设施可达性的空间分异样状况是合理配置医疗资源的前提。本文在回顾国内外关于医疗空间可达性研究的基础上, 采用两步移动搜索法, 以江苏省贫困县--东海县为案例, 以行政村和医院为分析单元, 基于迪卡斯特拉算法计算出各村到医院(卫生院)的最短通行时间, 进而分析各村医疗空间可达性分异情况。采用不用服务时间阈值范围进行空间敏感性分析, 综合研判缺医地区分布特点。与传统的医卫人员和人口比值的方法相比, 两步移动搜索法能有效显示县域范围内医疗可达性的空间分异情况。采用较大的时间阈值, 医疗空间可达性分异较为平滑, 采用较小服务阈值则空间分异显著, 缺医范围也较大。东海县医疗空间可达性整体呈单核结构, 并沿主要交通线延伸, 缺医地区多分布于边缘乡镇。提高边缘乡镇的行政村的甲级卫生院等级和乡村道路等级将会改善边缘乡镇的就医可达性。  相似文献   

16.
山东省乡村转型发展时空格局   总被引:13,自引:4,他引:9  
李婷婷  龙花楼 《地理研究》2014,33(3):490-500
依据乡村转型度、“人口-土地-产业”乡村发展三要素的两两协调度及乡村协调度,定量刻画了山东省乡村转型发展类型,揭示了1990-2009年期间各转型发展类型的特征和时空分布格局。结果表明:①山东省乡村转型发展普遍存在5种类型,依次为:产业低速转型低度协调型、要素平稳转型较低协调型、产业转型趋近土地转型中度协调型、产业转型超越土地转型较高协调型与土地和产业加速转型高度协调型。②乡村转型度与乡村协调度随协调转型度的增加呈现出对称分布特点;乡村转型度与乡村协调度呈现出局部周期性变动、总体趋势增加的变化特征。③产业转型与土地转型表现出很高的协调性;人口转型与土地转型之间的协调性及人口转型与产业转型之间的协调性均随转型程度加深而同步上升。④山东省乡村转型发展时空格局表现为:“八五”时期,山东省乡村地区加速转型,以乡镇企业快速发展为该时期主要特征;“九五”时期乡村转型发展类型普遍向转型速度较低的类型转变;“十五”时期乡村转型发展速度呈现出中心地区较低、边缘地区较高的特点;“十一五”时期乡村转型发展呈现空间均质化的稳定转型态势。  相似文献   

17.
朱琳  黎磊  刘素  李裕瑞 《地理研究》2019,38(3):535-549
村域是我国农村社会经济活动的基本单元,村域土地利用功能的合理发挥对于实现乡村振兴多元目标具有重要的理论和现实意义。本文首先对村域土地利用功能变化及影响机制进行了理论探究,然后以成都市郊区江家堰村为例,定量揭示了其发展转型过程中的土地利用功能变化、影响机制,提出了土地多功能利用助推乡村振兴途径。结果表明:① 土地利用功能因土地利用类型和土地利用方式变更发生变化,并受自然资源禀赋、社会经济条件、区域政策等间接影响,不同类型乡村其土地利用功能变化趋势往往不同;② 江家堰村经历了乡村旅游发展阶段、土地综合整治和生态建设阶段,其土地利用功能变化主要表现为生产功能转化为生产-生态复合功能,生活功能转化为生产-生活复合功能,土地利用功能呈现多元化和复合化特征;③ 大城市郊区乡村土地利用功能变化受自然因素、区位条件、产业转型、区域政策及土地利用主体等因素的综合影响。乡村振兴过程中,应充分发挥土地利用的多功能属性,促进乡村价值提升。  相似文献   

18.
Understanding and analysis of drivers of land-use and -cover change (LUCC) is a requisite to reduce and manage impacts and consequences of LUCC. The aim of the present study is to analyze drivers of LUCC in Southern Mexico and to see how these are used by different conceptual and methodological approaches for generating transition potential maps and how this influences the effectiveness to produce reliable LUCC models. Spatial factors were tested for their relation to main LUCC processes, and their importance as drivers for the periods 1993–2002 and 2002–2007 was evaluated by hierarchical partitioning analysis and logistic regression models. Tested variables included environmental and biophysical variables, location measures of infrastructure and of existing land use, fragmentation, and demographic and social variables. The most important factors show a marked persistence over time: deforestation is mainly driven by the distance of existing land uses; degradation and regeneration by the distance of existing disturbed forests. Nevertheless, the overall number of important factors decreases slightly for the second period. These drivers were used to produce transition potential maps calibrated with the 1993–2002 data by two different approaches: (1) weights of evidence (WoE) to represent the probabilities of dominant change processes, namely deforestation, forest degradation, and forest regeneration for temperate and tropical forests and (2) logistic RM that show the suitability regarding the different land-use and -cover (LUC) classes. Validation of the transition potential maps with the 2002–2007 data indicates a low precision with large differences between LUCC processes and methods. Areas of change evaluated by difference in potential showed that WoE produce transition potential maps that are more accurate for predicting LUCC than those produced with RM. Relative operating characteristic (ROC) statistics show that transition potential models based on RM do usually better predict areas of no change, but the difference is rather small. The poor performance of maps based on RM could be attributed to their too general representation of suitability for certain LUC classes when the goal is modeling complex LUCC and the LUC classes participate in several transitions. The application of a multimodel approach enables to better understand the relations of drivers to LUCC and the evaluation of model calibration based on spatial explanatory factors. This improved understanding of the capacity of LUCC models to produce accurate predictions is important for making better informed policy assessments and management recommendations to reduce deforestation.  相似文献   

19.
CLUE-S模型是一个基于经验统计原理的模拟多土地利用类型空间变化的动态模拟模型,它在世界多个国家和地区的区域尺度农业、森林为主的土地利用变化模拟中得到应用。作者对CLUE-S模型进行了改进,改进后的模型 (CLUE-SII) 引入了动态计算的邻域分析因子,可以对土地利用变化中的自发过程、自组织过程和土地利用类型间的竞争进行模拟,还可以根据研究区域特点构建不同的模拟方案,在这些模拟方案中,局地因子和邻域因子在土地利用变化中的作用方式不同。应用CLUE-SII对北京市海淀区1991~2001年土地利用变化进行了多方案模拟,结果表明邻域因子对城镇用地变化具有重要作用,其中将邻域因子看作自发过程放大因子的模拟方案获得了较好的模拟结果,整图符合比达到77%,其中城镇用地符合比达到82%,Kappa值达到0.754。CLUE-SII在北京市海淀区的应用实例表明,该模型可以对高分辨率和多土地利用类型下的城市扩展进行有效模拟,扩展了CLUE-S的应用领域;通过构建多模拟方案,不但可以探索最佳的模拟结果,还可以研究和分析不同土地利用驱动因子在土地利用变化中的作用模式。  相似文献   

20.
This paper examines the potential spatial impact of grocery store closures and their impact on the food accessibility of the population of one rural county in Southern Illinois. Additionally, we offer public health officials a simple method for locating populations at particular risk of food inaccessibility in the event of a grocery store closure. A model is introduced for weighting different types of food outlets based on the types of food products offered to potential customers. By using a weighted system for measuring different types of food outlets, individual addresses, and a novel method of visualizing food access, we find an improved means of locating areas of risk in a fluid food-access landscape.  相似文献   

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