An elephant in the planning room: Political demography and its influence on sustainable land-use planning in drylands     

D.E. Orenstein  L. JiangS.P. Hamburg 《Journal of Arid Environments》2011,75(6):596-611

Two distinct, conflicting, land-use planning paradigms affect drylands: one seeking environmentally sustainable outcomes and one addressing political-demographic concerns. The environmental paradigm is relatively new and is couched in the lexicon of sustainable development, combating desertification and biodiversity conservation. These concerns proscribe planning principles that allow for human settlement in drylands while minimizing its environmental impact. The latter paradigm has a longer history, born in central governments’ desire to secure sovereignty over outlying regions. These concerns result in planning goals that conflict with environmental goals. The environmental paradigm encourages compact development and efficient land-use, while the political-demographic one encourages in-migration of ‘friendly’ populations and the establishment of a physical presence on a maximum amount of land. Using Israel’s Negev Desert and China’s Xinjiang region as case studies, we suggest that successful implementation of sustainable dryland management depends on recognizing the challenge presented by political-demographic planning motivations. As such, successful implementation of environmental planning requires resolution of existing political conflicts. Since drylands are characteristically geographic and demographic frontiers, they are ideal settings in which to study the conflict between environmental and political-demographic goals and they provide an opportunity to better understand how this conflict creates a barrier to sustainable development.  相似文献   

基于OCCI的空间数据库几何对象实现方法   总被引：1，自引：1，他引：0  

吴杰 陆锋汤井田  程昌秀袁正午 《地球信息科学学报》2003,5(4):16-21

海量空间数据的高效访问和操作是 GIS平台和应用系统开发的核心技术。本文分析了 Oracle数据库管理系统所提供的访问接口 OCI、OCCI及对象类型转换工具 OTT的特性 ,基于 OCCI和 OTT技术提出了一种面向对象的访问及操作 SDO几何对象的方法 ,并通过实例讨论了实现过程。该方法利用 SDO几何模型作为 Oracle服务端的几何对象载体 ,在客户端通过继承 SDO几何对象实现自定义几何对象模型 ,避免了 SDO几何对象与用户定义几何对象之间的空间数据转换过程 ,有利于扩展自定义空间数据模型。同时 ,自定义几何对象可以充分利用Oracle Spatial提供的空间操作与整合功能 ,加速 GIS软件平台研发过程。  相似文献   

Perturbation of the Plane-Wave Reflectivity of A Depth-Dependent Elastic Medium By Weak Inhomogeneities     

M. Dietrich  F. Kormendi 《Geophysical Journal International》1990,100(2):203-214

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Evaluation of a water equivalent of snow cover map in a small catchment area using a geostatistical approach     

Jürg Hosang  Katrin Dettwiler 《水文研究》1991,5(3):283-290

We describe an objective method for evaluating the spatial distribution of water equivalents of the snow cover within a small catchment. Regression analysis is used to quantify the relationship between elevation, presence or absence of forest, and potential direct solar radiation as independent variables and water equivalent as measured at a number of sites. First, this regression relationship is used to interpolate water equivalent data all over the basin area. Then we interpolate the residuals of the regression using a geostatistical approach. Superimposing the results obtained by interpolating the regression relationship and the interpolated residuals eventually yields the water equivalent distribution over the test area. The advantages of the interpolation method used lie in the optimal (effective, unbiased) estimation of the interpolated values as well as in the possibility to quantify the associated estimation variances.  相似文献   

新密大平—超化滑动构造特征分析     

李诗芳  刘淑红  姚巧芝  刘建周 《河南国土资源》2001,(2)

本文从边界构造、滑动形态特征与力学性质、滑动系统、下伏系统、运动方向等方面 ,系统地分析研究了新密大平—超化滑动构造的总体特征。新密大平—超化滑动构造南北以背斜为界 ,东西受断层切割 ;滑面具有穿层现象且次级滑面发育 ;其力学性质为压扭性 ,南翼还兼有张性 ;滑动系统总体表现为向斜构造 ;滑动方向晚期呈现出先南后北的特征。  相似文献   

山区公路测设长度综合变形问题的研究     

刘传志 《测绘工程》2007,16(4):60-62

在分析公路控制测量长度综合变形来源、允许数值及国家统一坐标系统适用程度和范围的基础上,结合山区公路测量的特殊性,以贵州省板坝至江底公路某合同段坐标系选择为例,提出了山区公路测量坐标系选择方法,能较好地满足工程实际需求。  相似文献   

北京市建设项目竣工测量数据库研究与建立   总被引：1，自引：1，他引：0  

刘忠卿  秦学秀  任海英 《北京测绘》2007,(4):6-8,27

在分析空间数据库技术和ArcSDE数据存储技术的基础上,探讨了如何建立竣工测量成果数据库。对数据库结构和数据加工工艺进行了详细分析和说明。该数据库的建立可实现城市规划建设项目监督测量成果的计算机存储、管理和共享,有效提高竣工测量数据的利用率。  相似文献   

一种邻接区域平面元融合的桥面分割方法     

张兴岩  李琦  梁栋  蒲洁 《大地测量与地球动力学》2022,42(8):863-869

针对桥梁点云的桥面分割问题,提出一种邻接区域平面元融合的桥面分割方法。首先对点云进行体素化处理获得体素点云,利用超体素空间和法线约束准则进行桥梁点云过分割;然后利用面片法线的方向和模长进行面片过滤,获得包含桥面的候选面片;最后对候选面片进行邻接区域平面元融合,使用统计分布方法筛选融合区域,获得桥面点云。实验证明,该方法可以有效分割桥梁点云的桥面,稳定性较高且能保留体素化前的原始数据。相较于区域生长法和超体素区域生长法,该方法在跨区域融合方面有较好的抑制作用,更适用于桥梁点云的桥面分割。  相似文献   

准噶尔盆地车排子凸起东缘下切谷特征及其形成机制     

秦磊  李小刚  邱子瑶  李志军  徐少华  李仪汶  陈岑  汪佳蓓  文思奇 《现代地质》2021,35(3):832-840

下切谷是层序地层学研究的重要内容之一,同时也是寻找地层、岩性等圈闭的有利地区。综合利用钻测井、三维地震资料以及地震平面属性信息,在车排子凸起至红—车断裂带区域识别出下切谷沉积体系,对下切谷的发育特征以及形成机制进行分析,结果表明:地震振幅绝对值之和属性体显示研究区发育4条近东西流向的下切谷,主要表现为分支型和单一型的平面形态特征。在地震剖面上,几何形态以V形和U形为主,谷内沉积物充填样式有双向上超充填型和侧向加积充填型,同时具有加积、前积和上超等地震反射特征,属于“顺源堆积”与“溯源堆积”的交互沉积。结合准噶尔盆地车排子凸起中生代构造及气候演化特征分析认为,凸起东缘下切谷形成于晚侏罗世。该时期车排子凸起强烈隆升,相对湖平面急剧下降,河流侵蚀下伏地层导致下切谷形成。下切谷内沉积充填阶段发生在白垩纪。该时期车排子凸起剧烈下沉,相对湖平面上升,下切谷持续性的接受沉积充填。  相似文献   

Study on Retrieving Key Ecological Parameters in Mountainous Regions by Remote Sensing Methods and Evaluating Their Spatio-temporal Representativeness     

Ainong Li  Jinhu Bian  Gaofei Yin  Huaan Jin  Wei Zhao  Zhengjian Zhang  Xi Nan  Guangbin Lei 《地球科学进展》2018,33(2):141-151

Focusing on the Key Project of National Natural Science Foundation of China “A study on retrieving key ecological parameters in mountainous regions by remote sensing methods and evaluating their spatio-temporal representativeness”, this paper introduced the project background, objectives, research status, the key scientific questions, main contents of the research, the overall methodology and the deliverables. Choosing different topographic gradient and vegetation background, this project will conduct researches on retrieving key ecological parameters such as LAI and NPP in mountainous areas, evaluating their spatio-temporal representativeness, analyzing the influence of complex terrain on remote sensing signals and the remote sensing products, and finally trying to make a breakthrough in the theory and methodology of ecological parameters retrieving in mountains area.  相似文献