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1.
ON THE HIGHWAY NATURAL REGIONALIZATION OF CHINA 总被引：2，自引：0，他引：2
《地理学报》1978,(1)
ABSTRACT
The Highway Regionalization of China, which has been approved and tentatively adopted by the Ministry of Communication, is the first of its kind in China in the area of applied complex natural regionalization. It aims to bring out the regional differentiation of the natural conditions relevant to highway construction, and to provide engineering parameters and basic information on natural conditions of each region. It is worked out according to the theory of geographical zonation. Both "dominant factor" and "multiple factors" are used in selecting the criteria for iden-tifying regions. 相似文献
2.
《地理学报(英文版)》1978,(1)
ABSTRACT
The Highway Regionalization of China, which has been approved and tentatively adopted by the Ministry of Communication, is the first of its kind in China in the area of applied complex natural regionalization. It aims to bring out the regional differentiation of the natural conditions relevant to highway construction, and to provide engineering parameters and basic information on natural conditions of each region. It is worked out according to the theory of geographical zonation. Both "dominant factor" and "multiple factors" are used in selecting the criteria for iden-tifying regions. 相似文献
3.
吉林省西部土地沙化动态变化 总被引：1，自引：0，他引：1
The sandy land of the western part of Jilin Province is located in the ecotone of semi-humid and semi-arid area in the temperate zone of China. The sandy desertification has widely spread in the region because of the vulnerable natural conditions and the unreasonable human activity; as a result of this, the precious land resources and the economic development in the area have been seriously impacted. In this paper, the sandy land ecologic environment geographic information system is established based on the multi-spectral, multi-temporal Landsat TM images and field investigation. The comprehensive indexes of sandy desertification extent assessment which include vegetation degradation, wind erosion extent and soil depth are presented to classify the sandy land in western Jilin into three levels--slight, moderate and severe sandy desertification with the support of GIS platform. The results demonstrate that the sandy desertification has been partly controlled in the past twenty years, except some small sites. However, this doesn‘t necessarily mean that there is nothing for more concern. The two main causes of sandy desertification have not been eliminated yet, one is its natural factor, especially the physical and chemical characters of sandy soil and dry climate; another is the immoderate economic activity of human being that has highly accelerated the sandy desertification process. 相似文献
4.
The importance of relative relief as a geographic factor is gradually being realized, but its significance in relation to both physiography and human activities has hardly been appreciated. The present paper tries to elucidate relative relief in its manifold relations, using Tsunyi District of Kweichow Province as an example. 相似文献
5.
S.P.Chen 《地理学报(英文版)》1947,(2)
The importance of relative relief as a geographic factor is gradually being realized, but its significance in relation to both physiography and human activities has hardly been appreciated. The present paper tries to elucidate relative relief in its manifold relations, using Tsunyi District of Kweichow Province as an example. 相似文献
6.
森林生态系统健康评价指标在中国的应用 总被引：1，自引：0，他引：1
1IntroductionDuring recent two decades, the idea of "health" as an appropriate paradigm to assess the condition of ecosystems, is watchword of contemporary ecosystem management. The phrase "forest ecosystem health" has been used with increasing frequency in the context of forestry and natural resource management. Many scientists give the definitions from socio-economic and ecological perspectives (Rapport, 1992; USDA Forest Service, 1993; O'Laughlin, 1996; Allen, 2001). Forest health is a … 相似文献
7.
三江平原沼泽湿地时空动态特征 总被引：3，自引：0，他引：3
1IntroductionThe wetland ecosystem is the latest one understood by humans and it is the most seriously damaged ecosystem (Williams, 1991). The Sanjiang Plain, located in northeast China, is the largest concentrated area of freshwater wetland in China. Since the 1950s, large-scale reclamation of the marsh in the Sanjiang Plain has been started. According to statistics, the natural marsh has lost about 80% of its total area. The marsh resources in the Sanjiang Plain decreased greatly and the… 相似文献
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There is less than a decade left to accomplish the goal of ending global poverty by 2030. This paper investigates global poverty dynamics and finds a shift in the world's poverty gravity center from South Asia to Africa in the period 1990–2015. Sub-Saharan Africa has become the main battlefield for poverty reduction in the world. Global poverty reduction has been accompanied by political instability and local conflicts, economic marginalization, rural decline, and natural hazards as well as climate change which are jointly impacting the least developed areas and making the world's poverty reduction vulnerable to external shocks. The "STAR" scheme, including maintaining political stability, promoting targeted poverty alleviation, implementing regular assessments of poverty reduction initiatives, and revitalizing rural and poverty-stricken areas, is proposed with specific measures to enhance the resilience capacity of poverty alleviation in the world. 相似文献
11.
The fractal theory put forward by American mathematician B B Mandelbrot (1967) supplies an effective approach to solve complex
problems. The complex problems in geography have become the main positive study field of fractal theory. Based on the works
of China’s geographers and the summarization of contents of fractal theory, the authors comment on the present situation of
its applications to almost every branch of geography and discuss the related problems and the prospects of fractal study in
geography. 相似文献
12.
分形理论在地理学中的应用研究进展 总被引：62，自引：2，他引：60
美国数学家Mandelbrot提出的分形理论为解决复杂性问题提供了有效方法。地理学的复杂性问题已成为分形理论的重要实证研究领域。本文根据国内已有的文献,在概括分形理论主要内容的基础上,对地理学各分支领域的应用研究现状及有关问题进行了评述,并就地理学分形研究的前景作了展望。 相似文献
13.
分形理论在人文地理学中的应用研究 总被引：1，自引：0，他引：1
简介分形理论 ,并给出了四种常见分形维数 :Hausdorff维数、盒子维数、信息维数和关联维数的定义 ,探讨它在人文地理学各分支学科 (城市地理学、经济地理学、交通地理学 )的应用及其地理意义。 相似文献
14.
分形论、界壳论与山地研究理论及地理学创新和发展 总被引：5，自引：1，他引：5
在概述分形论、界壳论基本概念的基础上，首先探讨了二者对系统自组织理论的完善以及对深化山地研究和地理学研究的方法论意义；其次，总结了分形论、界壳论在山地理论和地理学中的已有应用，最后针对应用现状，对山地理论和地理学中理论的应用创新和发展提出了若干对策。 相似文献
15.
基于分形理论的土地利用景观格局变化研究——以长乐市为例 总被引：1，自引：0，他引：1
分形理论对地理学中具高度复杂结构的不稳定现象的研究具有良好的效果，为土地利用景观格局的定量描述提供了一条新途径，以分形理论为指导，在地理信息系统技术的支持下，结合多样性、破碎度景观指数，分析了长乐市1990—2000年土地利用景观类型各指数的变化情况：交通用地的分形维数最大，居民点及工矿用地稳定性指数增加，居民点及工矿、园地等受人类活动影响较大的土地利用类型尽管形态简单，复杂性较低，但是稳定性很强，而受人类影响小的自然土地覆被稳定性普遍较差，由此可为区域土地资源的合理利用提供若干参考。 相似文献
16.
丘陵山区城镇体系的分形特征——以江西省赣州市为例 总被引：1，自引：0，他引：1
运用分形理论,对赣州市城镇体系的规模分布和空间结构的分形特征进行了实证分析,得到以下结论:(1)在城镇规模分布方面,中等位序的城市较多,人口分布比较均衡,认为是一种较低水平的均衡;(2)在城镇空间结构方面,城镇空间分布呈现出集聚性特征,城镇的空间关联程度不够紧密,空间相互作用强度不大。在上述结论的基础上对赣州市城镇体系建设提出了建议。 相似文献
17.
城市地理研究中的单分形、多分形和自仿射分形 总被引：1，自引：0，他引：1
分形几何学在城市地理研究中具有广泛的应用,然而很多基本概念却让初学者感到迷惑。如何区分单分形、自仿射分形与多分形,是一个基本而重要的问题。简单分形容易理解,而真实的地理现象很少是单分形的。城市生长过程具有自仿射特征,而城市空间格局却具有多分形性质。作者发现,各种分形的共性在于三个方面：标度律、分数维和熵守恒。论文基于标度、分维和熵守恒公式,借助隐喻城市生长的规则分形来区分单分形、多分形和自仿射分形,讨论分形系统演化的机理、分形与空间自相关和空间异质性的联系,同时澄清一些在地理分形研究中的常见错误概念。最后以城市位序-规模分布为例,说明并对比单分形和多分形在城市地理研究中的建模与应用思路。 相似文献
18.
以滇西南地区临沧市2003～2008年各山地小城镇的人口规模数据为基础,运用城市地理学中的位序-规模法则、城市首位律及不平衡指数和自组织理论中的分形理论相结合的方法,对临沧市城镇体系规模等级结构进行定量和定性分析,从计量分析和分形研究两个方面对临沧市城镇体系规模等级结构特征进行总结,结果表明,临沧市城镇体系规模等级结构具有分形特征,处于低级平衡状态,发育还不成熟,但有开始走向成熟的趋势。最后根据临沧市城镇体系规模结构的特征提出相应发展建议。 相似文献
19.
分形理论在湿地科学中的应用现状与前景展望 总被引：10，自引：1，他引：9
分形理论是解决复杂性问题的独特理论体系。该文概述分形理论及湿地科学的性质和学科体系,将分形理论在我国湿地科学中的应用归结为5个领域,即湿地生物与生态学、湿地景观学、湿地土壤学、湿地地貌学和湿地沉积学。鉴于分形理论自身的不完善性以及当前湿地分形研究内容的不均衡性、不广泛性和不深入性等,分形理论及其在湿地科学中的应用依然面临很大的机遇与挑战。最后就分形理论在湿地科学中的应用前景进行展望,指出它的应用必将促进湿地研究的纵深化,并为湿地科学学科体系的发展做出重要贡献。 相似文献
20.
基于生态足迹模型的大庆市可持续发展动态评估 总被引：3，自引：1，他引：2
生态足迹作为定量测度区域可持续发展程度的有效指标,其核心是测量人类对自然生态服务的需求和自然所提供的生态服务之间的差距,使人类认识到自身生存发展对生态系统构成的压力状况,进而协助人类做出明智的选择。该文以我国能源重化工基地大庆市为研究区域,对其1980—2001年的生态足迹计算分析得出,该市1980年人均生态盈余为0．329hm^2,1988年为0．106hm^2;1992年生态足迹人均赤字为0．670hm^2,1996年为2．080hm^2,2001年为2．331hm^2。大庆市20多年来生态足迹由盈余发展到严重的赤字,表明其人口消费需求超过了自然生态系统的承载能力,生态环境呈现逐步恶化的趋势,可持续发展状况不容乐观。最后提出大庆市实现可持续发展的战略对策。 相似文献