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1.
为进一步分析上海市郊区农村居民点空间布局模式,以上海市松江区为典型区域进行实证研究,采用GIS查询统计和Voronoi图Cv值相结合的分析方法,通过计算点状目标的Voronoi多边形面积的变异系数(Cv值)方法来分析点状目标的空间分布特征。基于农村居民点不同类型的空间分布,提出布局优化措施。  相似文献   

2.
以典型喀斯特地区广西平果市的农村居民点为研究对象,运用GIS空间分析方法、Voronoi图和景观格局指数分析方法,揭示平果市喀斯特地区不同岩性上农村居民点的空间分布特征.结果表明:(1)平果市农村居民点总面积为4825.15 hm2,喀斯特地区与非喀斯特地区的农村居民面积比值约为2.8:1;(2)平果市的农村居民点属于...  相似文献   

3.
以福建省松溪县为例,对其下辖9个乡(镇)的农村居民点用地现状与特征进行了分析,并对全县农村居民点整治潜力进行了估算,认为该县农村居民点整治潜力较大。并以此为基础,提出了按照空心村整治模式、村庄归并模式、地质灾害区异地迁移安置模式、低山荒地整治模式、改造整理模式等农村居民点整治思路。  相似文献   

4.
选取喀斯特槽谷地区——重庆市石柱土家族自治县鱼池镇团结村农村居民点为研究对象,借助ArcGIS空间分析和地统计法,综合应用地貌-面积频度分布指数和信息熵分析了不同海拔、坡度、坡向、地形起伏度、地表粗糙度、剖面曲率和平面曲率7个地貌形态要素间农村居民点的分布特征。结果表明:①农村居民点分布的优势地形位分别为高程956.2~1000m,坡度5°~15°,坡向SW、W、NW和E,地形起伏度0~1m,地表粗糙度1.0~1.1,剖面曲率和平面曲率0°~5°的低地形位上;②在槽谷谷底,农村居民点信息熵的最大值为1.15,最小值为0.02,说明农村居民点在低地形位上分布的有序性较高。   相似文献   

5.
从西安市农村居民点的时空演变分析入手,通过分析西安市2010年、2015年和2020年的土地利用状况,提取西安市农村居民点分布图,分析了影响西安市农村居民点演化的相关因素,提出了农村居民点布局优化的对策。研究结果表明:西安市农村居民点呈现出由城市中心向外围扩散和由西北向东南迁移的趋势,而且数量增多、不断集聚;距离主城区的位置对农村居民点的分布具有影响,近年来农村居民点呈现向中长距离集中分布的趋势,城镇化率和经济发展水平与农村居民点的演化存在闭环循环促进机制,常住人口和人口密度的增加促进西安市农村居民点面积的增加,行政区划的变革,尤其是自然村和社区数量的变化,使得西安市农村居民点呈现出明显的集聚变化。据此提出强化集聚、改变经济理念和加强耕地保护的西安市农村居民点布局优化等对策建议。  相似文献   

6.
结合国内外土地整理研究动态分析了农村居民点用地整理的必要性及意义,介绍了农村居民点整理潜力分析的计算方法,并对山西省沁水县农村居民点整理潜力进行了分析及探讨了农村居民点的整理措施。结果表明,山西省沁水县2010年农村居民点整理总潜力为642 hm2,占农村居民点总面积的19.02%,主要来源于河谷平川、低山丘陵地区的宅基地超标面积,废弃建筑物压占,建筑废弃地以及居民点内的零星农用地。  相似文献   

7.
刘晓燕  刘峰  夏英晓  李刚 《山东地质》2011,(2):35-37,41
以烟台市牟平区为例,选用人均建设用地标准法、户均宅基地标准法和农村居民点内部土地闲置率法3种方法,对农村居民点土地整理潜力测算方法进行了比较研究。指出农村居民点整理潜力测算方法的选择要根据测算区域内农村居民点的用地结构、发展状况等实际情况进行确定。  相似文献   

8.
农村居民点整理是一项复杂的系统工程,整理潜力分析和效益评价是农村居民点整理项目投资前期工作的中心环节.是项目决策的依据。该文在分析睢宁县农村居民点整理潜力的基础上,对整理后的效益进行分析.为东部经济父发达地区的农村居民点整理提供了参考。  相似文献   

9.
基于环境经济领域的脱钩理论,对安徽省池州市近年来城镇建设用地与农村居民点变化的脱钩关系进行分析。运用脱钩指数计算模型与脱钩状态类型,构建脱钩模型,计算脱钩弹性系数。研究结果表明:脱钩形态不稳定,大部分年期没有表现出最理想的绝对脱钩形态;从动态演变来看,平稳过渡期脱钩形态是现实与理论相吻合的理想状态,剧烈波动期和预期理想脱钩形态不是理想状态;脱钩形态变化主要受农村人口和农村居民点变化影响;通过实施农村土地综合整治减少农村居民点规模,推进农业转移人口市民化,实现农村居民点和农村人口"双减",进而可以保持绝对脱钩形态;基于新型城镇化发展要求,应加大城镇土地节约集约利用力度,坚持城镇理性与精明增长理念,通过科学的村庄规划引领农村居民点合理布局,继续推进实施农村土地综合整治,并基于新型城镇化发展要求,稳定、有序推进农业转移人口市民化,促进土地城镇化与人口城镇化协调同步。  相似文献   

10.
以ArcGIS为平台,对汪清县农村居民点构建泰森多边形,形成Voronoi图,计算其面积的变异系数(Cv值),从村域尺度分析汪清县农村居民点的分布特征。结果显示:①汪清县东光镇、复兴镇、春阳镇和罗子沟镇属于集群分布类型;百草沟镇、大兴沟镇和天桥岭镇属于随机分布类型;鸡冠乡镇、汪清镇属于均匀分布类型。②农村居民点的分布与地形地貌、交通条件和河流水域等因素关系密切。从地形坡度上看,汪清县居民点随坡度升高,分布呈降低趋势;从道路交通上看,汪清县居民点随公路距离增大,分布密度降低;从河流水域上看,汪清县居民点随河流距离增加,分布密度降低。  相似文献   

11.
International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen.  相似文献   

12.
The Global Stratotype Section and Point (GSSP) for the base of the Silurian System was defined in 1985. Since that time, a number of researchers have suggested that this section has serious deficiencies for use as a GSSP. As a result, in 2000, the Subcommission on Silurian Stratigraphy (SSS) proposed undertaking a formal restu@ of this GSSP, which was subsequently approved by the International Commission of Stratigraphy (ICS). The result of this restudy was the formal proposal that the current GSSP, at 1.6 m above the base of the Birkhill Shale, at Dob's Linn, Scotland, should be maintained as the same locality and stratigraphic level, but the bios- tratigraphical definition of the boundary should be revised. The previously defined, basal Silurian grapto- lite zone, the Parakidograptus acuminatus Zone, should be subdivided into a lower Akidograptus ascensus Zone and a higher E acuminatus Zone. The base of the A. ascensus Zone, marked by the first appearance of A. ascensus, should be regarded as the biostratigraphic mark for the base of the Silurian. This proposal has now been formally approved by the SSS and ICS, and ratified by International Union of Geological Sciences. This is the first GSSP to undergo formal restudy and redefini- tion, and the proposal also included a recommended procedure for restudy of GSSPs.  相似文献   

13.
It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T 3 = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″.  相似文献   

14.
Important tendencies in development of the world mineral-resources sector at the beginning of the 21st century were an increase in production and consumption of mineral materials differentiated by types of metals and nonmetallic mineral raw materials, by countries and regions, as well as the concentration of the production of mineral raw materials in a small number of countries, and a reduction in industrial reserves of minerals in the world economy, even at the current stage of their extraction. These tendencies should be taken into account in working out a strategy for development of the Russian mineral raw-material base.  相似文献   

15.
Taking the example of W Sudan, an analysis of the climatic incidents leading to the two recent famine disasters is made. On this natural background, the human side is investigated. Focus is directed towards the fragile economic structure of the famine-prone population groups. An early-warning system for famine in the Sahelian Zone is proposed taking grain production and storage, livestock development and the relationship between the prices of livestock and grain as major indicators.  相似文献   

16.
东濮凹陷北部沙三中亚段广泛发育盐岩和烃源岩,这两个看似不能共存的物质却在这里互层共生。该时期研究区沉积特征为多盐韵律与多层烃源岩互层共生、连续沉积,单个盐韵律厚度从几米到十几米,烃源岩有机质丰度高、类型好。平面上,两者在湖盆沉积沉降中心共生;垂向上,高有机质丰度、好干酪根类型与高盐度地层具有较好的对应关系。因而成为恢复古气候和古环境的重要研究对象。通过岩石学、古生物学以及Sr/Ba、B/Ga、(V+Ni+Mn)、Fe/Mn、Sr/Cu、Mg/Ca、V/(V+Ni)、稀土元素含量和氯同位素等方法对凹陷北部沙三中亚段的沉积环境进行研究。结果表明,凹陷北部沙三中亚段为深水沉积的还原环境,古盐度较高,达到半咸水-咸水沉积;微量元素和孢粉化石特征表明研究区沙三中亚段为温暖潮湿的环境。  相似文献   

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The structure of the eastern Pyrenees consists mainly of south-directed thrusts involving basement and cover rocks. An antiformal stack developed by the piling up of basement thrust sheets which outcrop in the Axial zone. These structures account for a thin-skinned thrust model rather than a vertical fault model in which the Axial zone would be essentially autochthonous, and the North-Pyrenean fault the axial plane of a fan thrust system. New data from the Eastern Pyrenees and the thin-skinned model suggest that(1) the structure east of the Pedraforca nappe is similar to that of the Central Pyrenees; (2) the cover rocks of the South-Pyrenean units and of the Axial zone-after restoration—built up a northwards-thickening prism consistent with the existence of a unique Pyrenean sedimentary basin during Mesozoic time; (3) the Axial zone is only a complex antiformal stack developed as a part of South-Pyrenean system related to the Paleogene thrusting-tectonics. The Axial zone palaeogeographic area had no special meaning during Mesozoic time.  相似文献   

20.
In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning.  相似文献   

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