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中国城市土地利用效率及其溢出效应与影响因素   总被引:12,自引:2,他引:10  
王良健  李辉  石川 《地理学报》2015,70(11):1788-1799
基于C-D函数剔除城市经济非期望产出构建随机生产函数模型,以地均投入产出技术效率表征城市土地利用效率,采用2003-2012年282个地级以上市面板数据测算了中国城市土地利用效率,并建立空间滞后计量模型分析了城市土地利用效率的溢出效应与影响因素的区域差异。结果表明:① 中国城市土地利用效率有所提升,且存在明显的空间特征与区域差异。空间特征显示,效率较高的城市主要集中在珠三角、湖南、湖北、河南南部、安徽东部、山东与江苏交界处。区域差异显示,中部地区城市土地利用效率最高而东北地区最低,西北地区城市土地利用效率增速最快而西南地区较低且增速最慢;② 中国城市土地利用效率存在显著为正的溢出效应,其中在中部、东北、西北地区较高,而在西南地区最低;③ 影响因素在各区域对城市土地利用效率的作用存在明显差异,有必要采取具有区域针对性的措施提升城市土地利用效率。  相似文献   

3.
Land-use/land-cover changes (LUCCs) have links to both human and nature inter- actions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year inter- vals from the late 1980s to 2010, with standard procedures based on Landsat TM/ETM+ im- ages. A land-use dynamic regionalization method was proposed to analyze major land-use conversions. The spatiotemporal characteristics, differences, and causes of land-use changes at a national scale were then examined. The main findings are summarized as fol- lows. Land-use changes (LUCs) across China indicated a significant variation in spatial and temporal characteristics in the last 20 years (1990-2010). The area of cropland change de- creased in the south and increased in the north, but the total area remained almost un- changed. The reclaimed cropland was shifted from the northeast to the northwest. The built-up lands expanded rapidly, were mainly distributed in the east, and gradually spread out to central and western China. Woodland decreased first, and then increased, but desert area was the opposite. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included (1) an accelerated expansion of built-up land in the Huang-Huai-Hai region, the southeastern coastal areas, the midstream area of the Yangtze River, and the Sichuan Basin; (2) shifted land reclamation in the north from northeast China and eastern Inner Mongolia to the oasis agricultural areas in northwest China; (3) continuous transformation from rain-fed farmlands in northeast China to paddy fields; and (4) effective- ness of the "Grain for Green" project in the southern agricultural-pastoral ecotones of Inner Mongolia, the Loess Plateau, and southwestern mountainous areas. In the last two decades, although climate change in the north affected the change in cropland, policy regulation and economic driving forces were still the primary causes of LUC across China. During the first decade of the 21st century, the anthropogenic factors that drove variations in land-use pat- terns have shifted the emphasis from one-way land development to both development and conservation. The "dynamic regionalization method" was used to analyze changes in the spatial patterns of zoning boundaries, the internal characteristics of zones, and the growth and decrease of units. The results revealed "the pattern of the change process," namely the process of LUC and regional differences in characteristics at different stages. The growth and decrease of zones during this dynamic LUC zoning, variations in unit boundaries, and the characteristics of change intensities between the former and latter decades were examined. The patterns of alternative transformation between the "pattern" and "process" of land use and the causes for changes in different types and different regions of land use were explored.  相似文献   

4.
Land-use/land-cover changes (LUCCs) have links to both human and nature interactions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year intervals from the late 1980s to 2010,with standard procedures based on Landsat TM\ETM+ images. A land-use dynamic regionalization method was proposed to analyze major land-use conversions. The spatiotemporal characteristics,differences,and causes of land-use changes at a national scale were then examined. The main findings are summarized as follows. Land-use changes (LUCs) across China indicated a significant variation in spatial and temporal characteristics in the last 20 years (1990-2010). The area of cropland change decreased in the south and increased in the north,but the total area remained almost unchanged. The reclaimed cropland was shifted from the northeast to the northwest. The built-up lands expanded rapidly,were mainly distributed in the east,and gradually spread out to central and western China. Woodland decreased first,and then increased,but desert area was the opposite. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included (1) an accelerated expansion of built-up land in the Huang-Huai-Hai region,the southeastern coastal areas,the midstream area of the Yangtze River,and the Sichuan Basin;(2) shifted land reclamation in the north from northeast China and eastern Inner Mongolia to the oasis agricultural areas in northwest China;(3) continuous transformation from rain-fed farmlands in northeast China to paddy fields;and (4) effectiveness of the "Grain for Green" project in the southern agricultural-pastoral ecotones of Inner Mongolia,the Loess Plateau,and southwestern mountainous areas. In the last two decades,although climate change in the north affected the change in cropland,policy regulation and economic driving forces were still the primary causes of LUC across China. During the first decade of the 21st century,the anthropogenic factors that drove variations in land-use patterns have shifted the emphasis from one-way land development to both development and conservation.The "dynamic regionalization method" was used to analyze changes in the spatial patterns of zoning boundaries,the internal characteristics of zones,and the growth and decrease of units. The results revealed "the pattern of the change process," namely the process of LUC and regional differences in characteristics at different stages. The growth and decrease of zones during this dynamic LUC zoning,variations in unit boundaries,and the characteristics of change intensities between the former and latter decades were examined. The patterns of alternative transformation between the "pattern" and "process" of land use and the causes for changes in different types and different regions of land use were explored.  相似文献   

5.
Resettlement of people displaced by dam projects is an important development issue. Land lost due to the Three Gorges reservoir inundation and the adjustment of land-use policy in China resulted in land-use changes, and impacted on the human carrying capacity of the land and the land availability for resettlement. The Chinese government has implemented a ‘development-oriented resettlement’ policy and a ‘near resettlement’ approach to relocating rural dwellers affected by the Three Gorges Project (TGP). Based on recent land-use survey and population data of the case study area and using GIS-based multi-criteria analysis in land-use planning, this study analyses the characteristics and changes of land use in both the inundation and resettlement areas. Undeveloped land is scarce in both areas. The non-flooded cultivated land is distributed mainly on steep slopes (over 25 degrees). There is a discrepancy between the amount of land required by those being resettled and what is available in the designated resettlement communities. This study suggests that resettlement should consider the human carrying capacity of the land and, from a community standpoint, sheds light on the interplay between land-use planning and resettlement, and provides constructive suggestions for TGP resettlement strategies.  相似文献   

6.
White Rock Lake reservoir in Dallas, Texas contains a 150-cm sediment record of silty clay that documents land-use changes since its construction in 1912. Pollen analysis corroborates historical evidence that between 1912 and 1950 the watershed was primarily agricultural. Land disturbance by plowing coupled with strong and variable spring precipitation caused large amounts of sediment to enter the lake during this period. Diatoms were not preserved at this time probably because of low productivity compared to diatom dissolution by warm, alkaline water prior to burial in the sediments. After 1956, the watershed became progressively urbanized. Erosion decreased, land stabilized, and pollen of riparian trees increased as the lake water became somewhat less turbid. By 1986 the sediment record indicates that diatom productivity had increased beyond rates of diatom destruction. Neither increased nutrients nor reduced pesticides can account for increased diatom productivity, but grain size studies imply that before 1986 diatoms were light limited by high levels of turbidity. This study documents how reservoirs may relate to land-use practices and how watershed management could extend reservoir life and improve water quality.  相似文献   

7.
The paper presents a computationally efficient meta-modeling approach to spatially explicit uncertainty and sensitivity analysis in a cellular automata (CA) urban growth and land-use simulation model. The uncertainty and sensitivity of the model parameters are approximated using a meta-modeling method called polynomial chaos expansion (PCE). The parameter uncertainty and sensitivity measures obtained with PCE are compared with traditional Monte Carlo simulation results. The meta-modeling approach was found to reduce the number of model simulations necessary to arrive at stable sensitivity estimates. The quality of the results is comparable to the full-order modeling approach, which is computationally costly. The study shows that the meta-modeling approach can significantly reduce the computational effort of carrying out spatially explicit uncertainty and sensitivity analysis in the application of spatio-temporal models.  相似文献   

8.
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   

9.
近30年中国东北地区玉米种植体系的时空动态分析(英文)   总被引:4,自引:1,他引:4  
Understanding crop patterns and their changes on regional scale is a critical requirement for projecting agro-ecosystem dynamics. However, tools and methods for mapping the distribution of crop area and yield are still lacking. Based on the cross-entropy theory, a spatial production allocation model(SPAM) has been developed for presenting spatio-temporal dynamics of maize cropping system in Northeast China during 1980–2010. The simulated results indicated that(1) maize sown area expanded northwards to 48°N before 2000, after that the increased sown area mainly occurred in the central and southern parts of Northeast China. Meanwhile, maize also expanded eastwards to 127°E and lower elevation(less than 100 m) as well as higher elevation(mainly distributed between 200 m and 350 m);(2) maize yield has been greatly promoted for most planted area of Northeast China, especially in the planted zone between 42°N and 48°N, while the yield increase was relatively homogeneous without obvious longitudinal variations for whole region;(3) maize planting density increased gradually to a moderately high level over the investigated period, which reflected the trend of aggregation of maize cultivation driven by market demand.  相似文献   

10.
基于作物空间分配模型的东北三省春玉米时空分布特征   总被引:3,自引:0,他引:3  
利用1980-2010 年东北三省分县玉米播种面积与产量统计、耕地分布、农业灌溉分布以及作物适宜性分布等多源数据,结合基于交叉信息熵原理的作物空间分配模型(Spatial Production Allocation Model,SPAM),在5'×5'的像元尺度模拟了春玉米种植面积与产量的时空分布,并重点分析了两者在纬向、经向,以及高程上的时空变化规律。结果显示:(1)玉米种植面积在2000 年前向北扩展至北纬44°~48°间,2000 年后在中南部出现大规模发展(北纬42°~44°),并进一步向东扩展至东经123°~127°间,同时还表现为向低海拔(高程100 m以下)和较高海拔(高程200~350 m)扩展的态势;(2)单产在纬向上的增加区主要集中在北纬42°~48°,经向上的单产增加则相对均匀,高程上单产提升区主要集中在海拔350 m以下。(3)像元内玉米种植比例整体上由中低种植比例为主逐步演变为中高比例占据主体,并且中高种植比例像元对应的玉米单产水平整体上较高,反映了市场经济驱动下的玉米种植集聚化和规模化的发展趋势。  相似文献   

11.
公平导向的学校分配空间优化——以北京石景山区为例   总被引:6,自引:0,他引:6  
戴特奇  廖聪  胡科  张文新  刘正兵 《地理学报》2017,72(8):1476-1485
空间优化正从地理学的一个研究方向成为学科分支,但公平导向的公共服务空间分配优化研究还较薄弱。学区配置是这方面的一个典型问题,受到社会的广泛关注。针对“多校划片”的随机入学方式,以各居住小区所获得的教育质量期望值的方差来定义入学指标空间分配的公平程度,构建了以该方差最小化为目标、包含最大上学距离约束的二次规划模型,探求各小区对所获得指标进行随机抽签的情景下,各校入学指标在各小区的公平最大化分配,并以北京市石景山区为案例进行了应用研究。结果表明,在维持学校布局和师资配置现状的前提下,与“就近入学”相比,公平最大化的“多校划片”能以有限的上学距离代价,显著降低教育分配的空间差异。在最大上学距离为5 km的约束下,各小区教育质量期望值的方差降幅高达99%,教育质量期望值有所提升的小区或学生比例高达约2/3;付出的上学距离代价较显著但可接受,平均上学距离增加到3.99倍,达到3.20 km,仍低于案例区实际平均上学距离。当模型的最大上学距离参数从5 km逐步增至8 km时,教育公平的改善呈指数增长,平均上学距离呈算数增长;当距离为7 km时,各小区教育质量期望值的方差趋近于0,可基本实现上学机会的空间均等化。本文进一步讨论了优化结果对入学政策的启示。  相似文献   

12.
杨庆媛  毕国华  陈展图  曾黎  杨人豪 《地理学报》2018,73(11):2250-2266
实行耕地轮作休耕不仅是促进耕地休养生息、加快生态文明建设的重要任务,也是提高农业供给体系质量、实现农业与社会经济可持续发展的重要途径。本文从喀斯特生态脆弱区的人地关系特点出发,围绕休耕的目标导向及约束条件,厘定休耕地空间配置的逻辑内涵,在此基础上以国家休耕试点县——贵州省晴隆县为例,综合运用VSD脆弱性评估框架、灰色预测模型GM(1, 1)和GIS空间分析等方法,通过休耕地初判、休耕地修正、休耕地优选三个步骤实现休耕地的分区布局,据此探讨喀斯特生态脆弱区休耕地空间配置的实现路径与技术方法。结果表明:① 晴隆县耕地生态系统脆弱性较强,全县70%以上的耕地非常脆弱甚至极度脆弱,急需优化耕地利用方式,促进耕地生态修复。② 以粮食安全约束下的耕地保有量作为休耕规模的约束条件,依据耕地生态系统脆弱性由大到小进行筛选,得出晴隆县2015-2020年可休耕耕地规模共计13540.05 hm2,占全县耕地面积的37.18%。③ 根据休耕规模、耕地质量、地形地貌、交通区位、社会经济发展水平等方面的差异,晴隆县休耕地可按“三级五类”进行分区布局,具体布局休耕项目时要因地制宜,制定差异化的休耕模式及休耕组织方式。④ 休耕地的空间配置是一个“对象”和“规模”双重约束下的休耕地块优选问题,在此过程中,休耕对象诊断是基础,规模预测是约束,休耕项目布局是最终落脚点。  相似文献   

13.
主体功能区规划是新世纪以来我国在地域空间规划方面的一次重大创新和实践,"十二五"规划上升为国土空间开发和区域协调发展领域的国家战略之一。本文从改革开放以来我国区域发展失衡的三大主要问题:区域发展差距扩大、城镇化盲目、国土开发无序的分析入手,论述了通过地域空间规划确定合理的地域功能格局和国土空间开发结构的客观需求。进而探讨了地域功能的科学内涵和形成机制,揭示了自然生态本底功能和人类活动需求功能复合形成地域功能的过程;并结合主体功能区规划编制中的关键科学问题,如主体功能识别的指标体系选择、功能区的空间组织以及功能开发导向的确定等关键科学问题,探究了解决的具体路径和相关方案,并就支撑主体功能区规划实施的相关政策导向和改革框架进行了阐述。最后,从规划职责体系、空间规划体系和科技支撑体系三个方面对今后的实施、发展和完善主体功能区战略进行了讨论。  相似文献   

14.
A combined mineral magnetic and scaled chrysophyte study of lake sediments from Lake Lacawac and Lake Giles in northeastern Pennsylvania was conducted to determine the effects of land-use and sediment source changes on the variation of pH, conductivity, and alkalinity inferred from biotic changes. Ten 30–40 cm long gravity cores were collected from Lake Lacawac and three from Lake Giles. Isothermal remanent magnetizations (IRMs) were given to the lake sediments in a 1.3 T magnetic field to measure magnetic mineral concentration variations. IRM acquisition experiments were conducted to identify magnetic mineralogy. The bedrock, soils and a peat bog on the shores of Lake Lacawac were also sampled for magnetic analysis to determine possible lake sediment sources. The top 10 cm of sediment collected from Lakes Lacawac and Giles was two to four times more magnetic than deeper sediment. 210Pb dating suggests that this intensity increase commenced circa 1900. SEM images of magnetic extracts from the highly magnetic sediments indicates the presence of magnetic fly ash microspheres from fossil fuel burning electric power generation plants. The similarity in magnetic coercivity in the top 8 cm lake sediments and in the peat bog supports an atmospheric source for some of the magnetic minerals in the youngest lake sediments. The highly magnetic sediments also contain an antiferromagnetic mineral in two cores closest to Lake Lacawacs southeastern shore. This magnetic mineral is only present deep in the soil profile and would suggest erosion and significant land-use changes in the Lacawac watershed as another cause for the high magnetic intensities (concentrations) in the top 10 cm of the lake sediments. The most significant changes in the scaled chrysophyte flora occurred immediately above the 10 cm level and were used to infer a doubling of the specific conductivity between circa 1910 and 1929. These variations also support land-use changes in the Lacawac catchment at this time. A similar shift in the scaled chrysophte flora was not observed in the top of Lake Giles, however, distinct changes were found in the deeper sections of the core coupled with a smaller peak in magnetic concentration. Fourier analysis of the 210Pb-dated lake sediment magnetics indicates the presence of a 50 year period, low amplitude variation in the Lake Lacawac, Lake Giles, and Lake Waynewood (Lott et al., 1994) magnetic concentration records. After removal of the land-use/fly ash magnetic concentration peak by Gaussian filtering, the 50 year variation correlates strongly from lake to lake even though the lakes are in different watersheds separated by up to 30 km. When this magnetic variation is compared with Gaussian-filtered rainfall variations observed in New York City and Philadelphia over the past 120–250 years there is a strong correlation suggesting that magnetic concentration variations can record regional rainfall variations with an approximately 50 year period. This result indicates that magnetics could be used to document regional variations in climatic change.  相似文献   

15.
The implementation of integrated landscape management to support local and regional human well-being is crucial in arid regions,but its application to date is very limited.Although analytical frameworks have been established to maximize ecosystem services via trade-offs between different landscape configurations,consumption factors such as water resources are rarely and weakly considered in such frameworks.In this paper,an improved integrated landscape-management analysis framework,called the Consumption-integrated Landscape Management to Ecosystem Service(CLMES),is proposed.In this framework,consumption factors are integrated at the same level as ecosystem services.The improved analytical framework is then used to assess and optimize landscape design in the Ejina Oasis,an extremely arid region in western China.Three landscape conditions(past,current,and future)are evaluated,based on the CLMES.Our results indicate that the Heihe River water-allocation program effectively promoted ecosystem services in the Ejina Oasis from 2000 to 2011.However,the excessive expansion of cropland led to a slight decline in habitat quality.An optimized landscape configuration and policy suggestions are proposed,which may be beneficial to the improvement of total water-use efficiency,oasis stability,and resilience of the ecological?social system in the Ejina Oasis.  相似文献   

16.
黄土丘陵沟壑区水土流失的影响因素有气候、植被、土壤、地形等,而乔灌草植物在空间上的不合理配置是造成该区水土流失严重的主要原因之一。本文选择研究区内限制植物生长与分布的4个关键环境因子 (高程、坡度、坡向和降雨量),利用多属性决策分析(MCDA)的方法,探讨乔灌草植物在空间上的优化配置,将整个研究区划分为5类乔灌草植物空间优化配置主模式和18类乔灌草植物空间优化配置子模式;同时,应用GIS聚类分析与统计分析方法,对所划分的乔灌草植物空间优化配置模式进行空间布局分析。结果显示:农民赖以生存的经济林/农林复合配置模式和农田/庭院经济配置模式是研究区的主要配置模式,占配置模式总面积的76.02%。  相似文献   

17.
北上广深城市人口预测及其资源配置   总被引:2,自引:2,他引:2  
王勇  解延京  刘荣  张昊 《地理学报》2021,76(2):352-366
人口数量持续增长是困扰超大型城市发展的重要因素,适度人口为研究人口增长下的城市资源合理分配提供了较好的思路.本文以适度人口为切人点,利用可能—满意度模型测算北京、上海、广州和深圳4座超大型城市2035年适度人口规模,同时利用灰色BP神经网络模型预测各市2035年常住人口规模,并基于适度人口规模测算和常住人口规模预测结果...  相似文献   

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李建春  高玉婷  曲衍波  关梅  张勇  王森 《地理科学》2022,42(7):1155-1165
充分识别陆海空间冲突并制定科学规划是实现陆海统筹的关键。基于陆海空间利用现状与规划,构建陆海空间冲突的理论分析框架,采用冲突识别矩阵、邻域冲突测度模型和社会网络分析等方法,以山东省莱州市为案例区,1 km格网为研究单元,分别从陆地对海洋、海洋对陆地2个方向定量识别陆海空间的现状冲突和规划冲突,并结合四象限模型对冲突进行分区。主要研究结果如下:① 从冲突范围与强度来看,莱州市陆地利用与规划越过海岸线的范围更大,陆海交互冲突范围将持续增加,陆海统筹应重视空间复合利用与跨系统交互影响。② 从冲突的类型来看,现状冲突中陆地的水域与湿地以及海洋的渔业用海等利用方式对海陆系统产生的影响较大;而在规划冲突中,陆地的一般农地区和其他用地区,海洋的农渔业区和港口航运区4类功能分区跨系统产生的影响较大。③ 现状与规划的耦合分区结果显示,相对独立的陆海空间规划对于控制和缓解空间冲突具有一定效果,然而陆海空间统筹利用与管理迫在眉睫,应结合系统观点根据不同分区特点进行优化。  相似文献   

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复杂网络视角下的城市人流空间概念模型与研究框架   总被引:1,自引:0,他引:1  
罗桑扎西  甄峰  张姗琪 《地理研究》2021,40(4):1195-1208
城市内人流特征研究一直是城市地理学和城市空间研究的重要领域之一.针对已有相关研究存在仅侧重于从人口规模、密度视角分析空间分布及格局特征,而对隐藏于空间分布背后,因人流动而建立的空间交互关系关注不足的问题.本文以流空间理论、复杂网络理论、空间行为交互理论为理论基础,立足基于流、网络剖析城市内部空间中各要素间的相互作用及关...  相似文献   

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