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1.
平泉县生态功能区划与主体功能区划研究   总被引:4,自引:0,他引:4  
探讨生态功能区划和主体功能区划的内涵及其相互关系,对主体功能区划的思路、指标、技术方法等进行探索性研究,并应用于县级区划实践。结论如下:1)生态功能区划与主体功能区划既相互区别又相互联系,前者以保护生态环境为主要功能,后者以调控和规范区域开发行为为主要功能,作用范围更广且作用力更强。2)建立主体功能区划的5个约束性指标,即生态系统弹性力、资源承载力、环境承载力、现有开发密度和未来社会经济发展潜力;提出"反规划"的区划方法和技术路线,即按照禁止开发、限制开发、优化开发和重点开发的顺序进行主体功能区划。3)首次对平泉县进行两区划的同步编制,将全县划分为2个一级生态功能区和7个二级生态功能区,在此基础上进行4类主体功能区划分,并提出相应的空间管制措施。  相似文献   

2.
Territory or zone design processes entail partitioning a geographic space, organized as a set of areal units, into different regions or zones according to a specific set of criteria that are dependent on the application context. In most cases, the aim is to create zones of approximately equal sizes (zones with equal numbers of inhabitants, same average sales, etc.). However, some of the new applications that have emerged, particularly in the context of sustainable development policies, are aimed at defining zones of a predetermined, though not necessarily similar, size. In addition, the zones should be built around a given set of seeds. This type of partitioning has not been sufficiently researched; therefore, there are no known approaches for automated zone delimitation. This study proposes a new method based on a discrete version of the adaptive additively weighted Voronoi diagram that makes it possible to partition a two-dimensional space into zones of specific sizes, taking both the position and the weight of each seed into account. The method consists of repeatedly solving a traditional additively weighted Voronoi diagram, so that each seed's weight is updated at every iteration. The zones are geographically connected using a metric based on the shortest path. Tests conducted on the extensive farming system of three municipalities in Castile-La Mancha (Spain) have established that the proposed heuristic procedure is valid for solving this type of partitioning problem. Nevertheless, these tests confirmed that the given seed position determines the spatial configuration the method must solve and this may have a great impact on the resulting partition.  相似文献   

3.
中国西北地区长期面临资源组合不匹配、区域发展不平衡的问题,而空间区位又决定了其具备促进区域协调、沟通国际国内、调整经济结构、筑牢生态屏障的战略地位。建设具有引领作用的生态经济枢纽区,将有助于改善西北及全国的生态环境问题、提升全域生态安全水平,同时也对国家经济发展具有推动作用。本文立足中国西北“水三线”空间格局,依据国家战略定位与生态经济功能,基于对研究区人地环境、城市群与城镇发展体系、人口布局与民族构成的全面解析,解读生态经济枢纽区的基本内涵,其可归纳为生态功能区、经济枢纽区、文化融生区、深陆通道区四个方面。进一步,本文综合宏观布局、资源禀赋、生态环境、陆海统筹等视角,阐明了生态经济枢纽区建设的功能定位,构建了西北“水三线”地区极点带动、轴带支撑的总体空间布局。并提出河西、兰西、天山北坡、环塔里木盆地绿洲四大生态经济枢纽区的建设格局与发展途径,探索了生态经济枢纽区与国家战略布局的互动关系。以期助力中国新时期西部大开发形成新格局,为中国“一带一路”的“深陆”研究提供科学依据。  相似文献   

4.
唐承丽  吴艳  周国华 《地理研究》2018,37(2):292-306
城市群、产业集群与开发区的协同发展是实现城市群地区可持续快速发展的重要手段。在已有文献研究的基础上,基于宏观与微观相结合的视角,梳理了城市群、产业集群与开发区三者之间的关系及互动机制。认为城市群是新型城镇化的主体形态,是产业集群和开发区发展的空间载体,城市群为开发区和产业集群发展提供生产要素、服务和市场;开发区是城市群的创新创业高地与产业集聚、集群发展的重要场所,是城市群的重要生产功能区;产业集群是产业发展的重要组织形式,是推动开发区和城市群发展的重要驱动力。产业集群与开发区共享着城市群的资源与服务,开发区通过产业集聚与创新,产业集群通过产业链延伸、耦合与创新,与城市群形成生产要素、市场交易、创新与服务等方面的多维度相互作用,最终实现三者的协同发展。基于城市群、产业集群与开发区规模、结构、职能和创新等4个方面的17个指标,采用典型相关分析法,以长株潭城市群为案例区,对城市群、产业集群与开发区两大变量组进行了互动因素与强度的量化分析,结果表明:① 长株潭城市群、产业集群与开发区已形成有效互动。其中,城市群通过经济规模、城市结构、创新投入与产出、服务职能的发展,促进产业集群的经济规模、产业集聚、经济效益与产业创新,以及开发区的建设品质、产业集聚与产业效率的发展。开发区通过产业集聚与创新效率的提高,产业集群通过产业规模、效益协同开发区效率的提升,强化了城市群规模、结构、创新与职能的发展。② 长株潭城市群通过经济规模、结构、创新与服务四类因子,对产业集群与开发区产生了全面的促进作用,但产业集群与开发区并未完全协同地促进城市群发展。③ 要进一步提升产业集群的效益与开发区的效率,加强其对城市群发展与繁荣的支撑作用,全面实现三者的多维良性互动,提高城市群的核心竞争力。  相似文献   

5.
境外经贸合作区已经成为中国实施“走出去”战略和建设“一带一路”的重要平台和空间策略。文章在总结中国境外经贸合作区发展特点基础上,采用实地调研与深度访谈的方法分析了中国-老挝万象赛色塔综合开发区的开发模式,并基于企业视角分析了该开发区的优劣势。结果发现:1)园区是采取“项目建设+土地抵偿”的形式进行开发的典型项目,以符合东道国国情与需要为发展定位,主要通过土地增值、为跨国企业提供厂地的方式获取收益;2)园区发展优势表现在:受到双边政府的大力支持,税收优惠力度大,区位优势明显;园区发展劣势表现在:产业链体系不完整、企业境外融资难度大、企业在当地的根植性弱、企业间凝聚力不足、劳动力资源匮乏、劳动技能与效率尚待提高、投资汇回利润存在一定风险、市场开发尚且不足。在此基础上,提出未来研究应重点关注中国境外经贸合作区的区位选择与产业布局、本地嵌入机制、经济地理影响等方面,并探讨了本案例对中国境外经贸合作区建设的政策启示,即,加强政府间磋商、契合东道国发展需要,加强对本地劳动力的职业培训是保障中国境外经贸合作区顺利发展的关键。  相似文献   

6.
京津冀协同发展和北京市非首都功能疏解政策实施状况是当前学术界和政府关注的热点。城市功能的分布和互动格局是刻画城市群协同发展和治理策略成效的重要内容。本文在阐述城市群内城市功能之间互动原理基础上,引入偏离—份额分析模型、改进土地生态位模型、扩展引力模型和GIS技术,耦合构建了新的城市功能互动模型。以京津冀城市群为研究对象,基于2010年、2016年、2019年3期POI大数据提取不同类别城市功能区,从时空两个维度揭示京津冀城市群功能的互动格局特征,分析协同发展和北京市非首都功能疏解政策实施状况,并有针对性地提出了治理策略。结论显示:① 2010—2019年间城市群建成区城市功能区总面积增加1.5倍,其中混合功能区增长最快,增加1.7倍;② 北京市工业功能、商业功能正在稳步疏解,但是居住功能、科教文化功能、公共服务功能仍在聚集与强化;③ 廊坊市、唐山市、天津市、保定市等中部城市在非首都功能疏解中发挥了“二传手”作用,成为功能互动的主要驱动城市;④ 石家庄市吸纳的疏解功能主要来源于天津市和廊坊市,具有接力特征;⑤ 京津冀城市群城市功能疏解在治理策略上需要关注功能互动格局演化趋势来进行精准施策。上述结论表明本文构建的城市功能互动模型可以较好地揭示和解释京津冀城市群城市功能互动格局的变化特征。  相似文献   

7.
Safety zones are areas where firefighters can retreat to in order to avoid bodily harm when threatened by burnover or entrapment from wildland fire. At present, safety zones are primarily designated by firefighting personnel as part of daily fire management activities. Though critical to safety zone assessment, the effectiveness of this approach is inherently limited by the individual firefighter’s or crew boss’s ability to accurately and consistently interpret vegetation conditions, topography, and spatial characteristics of potential safety zones (e.g. area and geometry of a forest clearing). In order to facilitate the safety zone identification and characterization process, this study introduces a new metric for safety zone evaluation: the Safe Separation Distance Score (SSDS). The SSDS is a numerical representation of the relative suitability of a given area as a safety zone according to its size, geometry, and surrounding vegetation height. This paper describes an algorithm for calculating pixel-based and polygon-based SSDS from lidar data. SSDS is calculated for every potential safety zone within a lidar dataset covering Tahoe National Forest, California, USA. A total of 2367 potential safety zones with an SSDS ≥1 were mapped, representing areas that are suitable for fires burning in low wind and low slope conditions. The highest SSDS calculated within the study area was 9.65, a score that represents suitability in the highest wind-steepest slope conditions. Potential safety zones were clustered in space, with areas in the northern and eastern portions of the National Forest containing an abundance of safety zones while areas to the south and west were completely devoid of them. SSDS can be calculated for potential safety zones in advance of firefighting, and can allow firefighters to carefully compare and select safety zones based on their location, terrain, and wind conditions. This technique shows promise as a standard method for objectively identifying and ranking safety zones on a spatial basis.  相似文献   

8.
We invert differential SdS-SS traveltime residuals measured from stacked waveforms and finite-frequency sensitivity kernels for topography on the 410- and 660-km discontinuities. This approach yields higher resolution images of transition zone thickness than previous stacking methods, which simply average/smooth over topographic features. Apparent structure measured using simple stacking is highly dependent upon the bin size of each stack. By inverting for discontinuity topography with a variety of bin sizes, we can more accurately calculate the true structure. The inverted transition zone model is similar to simple stack models with an average thickness of 242 km, but the lateral variations in thickness are larger in amplitude and smaller in scale. Fast seismic velocities in 3-D mantle models such as SB4L18 correlate with areas of thicker transition zone. The elongated curvilinear regions of thickened transition zone that occur near subduction zones are narrow and high amplitude, which suggests relatively little lateral spreading and warming of subducted lithosphere within the transition zone. The anomalously thin transition zone regions are laterally narrow, and not broadly continuous. If these variations in transition zone thickness are interpreted as thermal in nature, then this model suggests significant temperature variations on small lateral scales.  相似文献   

9.
以宁夏盐池县为例,基于前期宁夏限制开发生态区主体功能细分方案,利用农户调查数据,采用Logistic回归模型分析了农户生态补偿的参与意愿及影响因素。结论包括:(1)农户对生态补偿政策的满意度较高,不同类型区农户对政策的满意度有明显差异。(2)农户对政策的认知不高,弱限制开发区农户对生态补偿政策的认知最高,中限制开发区、禁止开发区农户的认知水平次之,强限制开发区农户的认知水平最低。(3)农户生态补偿的参与意愿较高,各类型区在空间上具有明显差异。(4)前期政策满意度、人均耕地面积、人均草地面积、羊只存栏量、户主年龄、农户家庭收入情况、非农收入比重等指标对农户参与生态补偿政策的意愿有显著影响。其中,先期政策满意度、农户家庭收入情况、非农收入比重等指标具有正向作用,其他指标具有负向作用。  相似文献   

10.
周道玮  王婷  王智颖  李强  黄迎新 《地理科学》2020,40(10):1731-1741
为了草地农业区域优化发展,依W Koppen世界气候分类途径,进行了中国气候分类及草地农业气候分区,依据相应途径,制作了中国饲草寒冷度分区图和中国饲草炎热度分区图,分析了各饲草气候区适宜的饲草作物种类及管理对策。中国气候及草地农业气候有17个类型,归并为6个饲草气候系统,中国饲草寒冷度分11个区,中国饲草炎热度分8个区。每个气候系统及寒冷度分区和炎热度分区内,分别有适宜的饲草作物,其评价标准为:生态适应、生长状态正常、发挥潜在遗传产量、有经济效益。干旱饲草气候系统发展低密度放牧饲养,湿润饲草气候系统发展规模化集约饲养,为中国草地畜牧业生产模式的基本理论选择。  相似文献   

11.
南迦巴瓦峰与托木尔峰山地垂直自然带的比较   总被引:2,自引:0,他引:2  
徐慧  彭补拙 《山地学报》2002,20(4):432-437
南迦巴瓦峰地处喜马拉雅山脉东端雅鲁藏布江大拐弯的内侧,托木尔峰地处天山山脉的西端,二者独特的自然地理特征及其高大的山体为山地垂直自然带谱的形成和发展提从了十分有利的自然环境,发育了相当完整的山地垂直系列。比较二者的垂直带谱,可以发现无论在垂直带谱的形成条件,基带,性质和结构类型,还是景观特征,垂直分异影响因素及南北坡差异程度等方面,都存在着较大的差异。南峰垂直带谱为以森林-草原-荒漠土壤系列为特征的季风性湿润,法湿润带谱系统,垂直分异的主导因素为温度;托峰垂直带谱为以荒漠--草原-荒漠土壤系列为特征的大陆性干旱带谱系统,垂直分异的主导因素为湿度。不同的垂直自然带特征决定了不同的资源开发利用和保护措施。  相似文献   

12.
基于GIS的耕地改良利用分区研究——以山东章丘市为例   总被引:3,自引:0,他引:3  
以山东章丘市为研究区,运用GIS技术,在确定耕地改良利用分区因子和标准的前提下,对区域内全部耕地状况及其障碍因素进行定量分析,划分耕地改良利用类型区.按照因地制宜、因土适用的原则,提出相应的改良利用措施,旨在摸清研究区域耕地改良利用因素的现状水平及制约耕地利用的障碍性因素,进一步提高其高产田的生产能力,挖掘中低产田的生产潜力,探索耕地改良利用的新思路和新方法,为其它区域耕地资源的科学管理和可持续利用提供指导和借鉴作用.  相似文献   

13.
东亚地区森林植被带的三维空间分布   总被引:10,自引:3,他引:10  
方精云 《地理学报》1995,50(2):160-167
东亚森林植被带主要由热带亚热带雨林(季雨林)、暖温带常绿阔叶林、冷温带落中阔叶林和亚寒带针叶林组成。这些植被带的垂直分布高度随纬度(温度梯度)和经度(干湿度梯度)的不同而变化,本文根据大量的地植物学资料,从生态气候学的角度研究了这种变化的规律性并给予了定理的表达。结果表明,在湿润气候区,各森林植被带的分布高度随纬度的增加而下降,下降趋势能用多级正弦函数来表达,随着经度的增加(由内陆向沿海变化),各  相似文献   

14.
Reasonable development and utilization of spatial resources in the coastal zone not only affects the development quality of the marine economy but also impacts the utilization efficiency of spatial resources,playing an important role in regional sustainable development.Depending on the natural,economic,and societal characteristics of a region,research topics such as using relevant methods to divide the coastline,proper spatial development of the coast,protecting coastal zones,and achieving higher spatial resource distribution efficiency have recently become hot topics in geographic research.Most of the scholars construct the evaluation index system from the perspective of economic and ecological factors and undertake some exploration of the division methods.However,the selection of indicators for a coastal zone needs a different and more scientific approach.There is a need for emphasizing the overall strategy of land-ocean integration in developing spatial resources in a coastal zone.Taking the coastal zone in Ningbo as an example,this paper develops a new evaluation framework and spatial function regionalization method that is used to divide the coastline and coastal zone.Based on the perspective of overall strategy for the land and ocean,we evaluate the suitability of coastline development.We then propose the spatial function regionalization of the coastal zone.Finally,based on the status quo of spatial development in Ningbo,we divide the coastal zone into ecological space,production space and living space,and propose adjustment directions and control requirements for the different types of spatial layouts.  相似文献   

15.
Reasonable development and utilization of spatial resources in the coastal zone not only affects the development quality of the marine economy but also impacts the utilization efficiency of spatial resources, playing an important role in regional sustainable development. Depending on the natural, economic, and societal characteristics of a region, research topics such as using relevant methods to divide the coastline, proper spatial development of the coast, protecting coastal zones, and achieving higher spatial resource distribution efficiency have recently become hot topics in geographic research. Most of the scholars construct the evaluation index system from the perspective of economic and ecological factors and undertake some exploration of the division methods. However, the selection of indicators for a coastal zone needs a different and more scientific approach. There is a need for emphasizing the overall strategy of land-ocean integration in developing spatial resources in a coastal zone. Taking the coastal zone in Ningbo as an example, this paper develops a new evaluation framework and spatial function regionalization method that is used to divide the coastline and coastal zone. Based on the perspective of overall strategy for the land and ocean, we evaluate the suitability of coastline development. We then propose the spatial function regionalization of the coastal zone. Finally, based on the status quo of spatial development in Ningbo, we divide the coastal zone into ecological space, production space and living space, and propose adjustment directions and control requirements for the different types of spatial layouts.  相似文献   

16.
南极冰盖的融化对全球海平面上升和气候环境变化具有重要影响,合成孔径雷达(SAR)用于划分南极冰盖冰川带及冻融探测具有不可替代的作用。本文以南极半岛地区为例,基于C波段星载SAR影像进行南极冰盖冻融探测方法研究。通过对于南极冰盖干雪带、渗浸带和湿雪带的后向散射特征的分析,采用基于后向散射因子阈值的决策树分类划分冰盖冰川带。统计分析表明,冰川带后向散射因子分布并不集中,尤其是融化强烈时的湿雪带受融化程度影响很大,与干雪带相近而不能仅从后向散射因子数值区分。为将冰盖的冰川带分类,引入干雪带分布和海拔高度作为辅助信息,分别发展了两种决策树分类方法并比较分析,同时利用微波辐射计冰盖冻融探测结果和自动气象站数据做验证。结果表明利用双极化SAR数据的后向散射因子基于两种决策树分类都能够有效地划分冰川带并区分冻融状态,实现高分辨率的冰盖冻融探测。  相似文献   

17.
李郇 《热带地理》2001,21(1):11-16
在论述经济技术开发区、高新技术开发与新型城区关系的基础上,依据城市空间自组织演化理论,提出按开放式的网络结构建设广州经济技术开发区与高新技术开发区新型城区的构想,并提出相应的创新网络、产业网络、基础设施网络和组织网络的建设策略。  相似文献   

18.
The Singapore River thematic zone: sustainable tourism in an urban context   总被引:5,自引:0,他引:5  
This paper explores the concept of sustainable tourism and how it applies to urban destinations such as Singapore. As tourism is an important industry in Singapore, in terms of employment, business activity and an income generator, the Singapore Tourism Board is continuously looking at potential avenues to make Singapore a competitive destination. We examine the use of thematic zones in Singapore as a strategy to achieve its ambition of becoming a tourism capital of the world. By focusing on a case study of the Singapore River thematic zone (one of the 11 thematic zones identified by the Singapore Tourism Board), we assess the viability of thematic zones in ensuring sustainable urban tourism. The paper closes with some theoretical reflections and policy implications arising from our key findings.  相似文献   

19.
Summary The thermomechanical differential equations governing deformation in viscous shear zones have been solved for both constant velocity and constant stress boundary conditions. The solutions show that the inertial term in these equations can be neglected everywhere.
The starting condition of the constant velocity model has been shown to be a constant velocity gradient and not a Heaviside function. The temperature anomaly produced by shear heating at the centre of the shear zone is shown to increase gradually and continuously with time, not reaching an asymptotic value. Conclusions for the constant velocity boundary condition are otherwise generally similar to those presented by Yuen et al , and agree with Fleitout & Froidevaux. The temperatures reached by constant velocity shears are sufficient for partial melting.
Constant stress boundary condition shear zone models show an initially broad shear zone with uniform shear velocity gradient. Depending on the level of applied shear stress and ambient temperature, localized intense shear heating may develop followed by thermal runaway. At lower ambient temperatures relatively high stresses are required to produce thermal runaway.
The broadening of the constant velocity shear zone proceeds more rapidly with increased ambient temperature. This can be used to show that shear zones broaden with depth. The merging of parallel shear zone pairs has been investigated and shear zones separated by distances of less than 10km coalesce to form a single shear zone within 3 Myr. Only shear zones separated by 50km or more remain distinct over periods of tens of millions of years.  相似文献   

20.
周娜  雷加强  王永东  尤源 《中国沙漠》2015,35(6):1683-1692
利用1973-2010年12个站点的年平均气温、降水量、风向、风速数据,对38 a来毛里塔尼亚气候变化和风况特征作了初步分析。结果表明:毛里塔尼亚沿海区域38 a来呈变暖趋势,北部荒漠区域和南部热带草原区域则呈现冷暖交替变化的趋势。20世纪60年代降雨量最多,70年代和80年代降雨量偏少,总体上降雨量略有减少。除沿海区域外,南部热带草原区域和北部荒漠区域少雨期和降温期相对应,多雨期与升温期相对应,降雨滞后于温度。1973-2010年月平均风速均呈现下降趋势,南部热带草原区域下降趋势较为明显,北部荒漠区域下降趋势不明显。月平均风速为春季、夏季较大,冬季次之,秋季最小。季节风热条件存在明显差异,北部风热同步,南部先同步后异步,沿海则完全不同步。各站点的年风向频率,沿海区域以北风为主,而北部荒漠区域及南部热带草原区域风向则介于东、北向之间。  相似文献   

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