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1.
非平面应变状态下岩石体积变化的估算,一直是世界上悬而未决的问题。本文初步完善了实用于非平面应变状态下岩石体积变化的计算公式,并用这些公式计算了粤北新洲推覆体同推覆期的岩石体积变化。结果表明,在逆冲推覆时期,整个外来系统普遍发生了强烈的压溶-迁出作用.由此造成的岩石体积损耗平均达22.88%。同推覆期外来系统的巨大体耗,与同推覆期含金动力分异热液的形成和演化以及该区石英脉型金矿床成矿物质来源之间有着密切的内在联系.  相似文献   

2.
1INTRODUCTION The circular-economyisan efficient resources metabolic process, based on principles of ecology and system engi- neering.Withcoupledstructure andthe complex ecolo- gical and economic evolution, it has the characteristics of overall integrity, coordination, and circulation (WANG, 2005). Compared with the traditionalecono- mic model, the circular-economy requires the technical model of production process to be changed from the opening flow pattern that is "resourcesconsumption…  相似文献   

3.
Based on Tupu theory, this paper studied the dynamic changes, conversion modes, expansion intensity and landscape attributes of the saline-alkali lands in Changling County, Zhenlai County and Da'an City of the western Jilin Province in 1980-2000 with the help of GIS. The results show that the saline-alkali land rather sharply increased in Da'an during 1995-2000; the main conversion processes in the three counties were from grassland to saline-alkali land and from saline-alkali land to grassland; and the typical shapes, spatial expansion speed and mode, and landscape attributes of the saline-alkali land were different in the three counties, which were closely related to local topography, predominant wind orientation, water resources distribution, etc. The corresponding spatial expansion mode was marginality in Changling, random in Zhenlai and more kernels in Da'an, respectively. Landscape attributes also responded to the spatial-temporal dynamic changes of the saline-alkali land and the landscape indices of Da'an fluctuated greatly. The frame of this research may provide fundamental reference for landscape analysis and give some suggestions for regional sustainable development.  相似文献   

4.
It has been long believed there should be some relations between traffic system and urbanization,but the in-teraction between them,especially on the regional level,has been not in consideration due to the difficulty in quantitative analysis.Based on the development of Jilin Province during 1981-2003,the paper analyzed the relation with the grey-relation model which was adjusted to fit specific problem,and came to some conclusions.Firstly,there exists ob-vious and strong correlation between traffic system and urbanization.Secondly,urbanization responds to the develop-ment of traffic system mainly on the level of urbanization,such as population and developed area,however,less on urbanization quality.Thirdly,traffic system influences urbanization as a whole except for several peculiar factors,which means we should optimize the whole traffic system to promote urbanization.Based on those conclusions,the paper illustrated the mechanism of traffic system,promoting urbanization scale and urbanization quality.  相似文献   

5.
By establishing the interpreting elements, and applying supervised classification, the sandy desertification was interpreted and the desertified land areas of the counties in the western Jilin Province in 1986 and in 2000 were obtained. Taking Tongyu and Qian‘an as examples, the natural driving forces and man-made driving forces were analyzed. The paper comes the conclusions that the material sources and the warming and dry climate are the internal causes of potential land descrtification: the irrational human activities, such as destroying forest and reclaiming the grassland, are the external causes of potential land desertification; while more rational human activities, such as planting trees and restoring grassland can reverse the land desertification. Furthermore, the countermeasures and suggestions for the development of agriculture and animal husbandry in the western Jilin Province are put forward.  相似文献   

6.
1IN TR O D U C TIO NEco-security is the state in w hich the resources,envi-ronm entand ecosystem s thatconcern people are secure(M Aetal.,2004;SH Ietal.,2004).O therw ise,w e calliteco-security problem or ecologicalrisk.The eco-se-curity isdraw ing the in…  相似文献   

7.
THE EVALUATION AND ANALYSIS OF THE TOURISM RESOURCES IN JILIN PROVINCE   总被引:1,自引:0,他引:1  
This paper comprehensively evaluates and analyzes the tourism resources in Jilin Province,China.And it consists of three parts.The first two parts are on the resources evaluation and analysis.Based on the results of evaluation about the structural and spatial distribution of the tourism resources,it is found that ,the natural resources play fundamen-tal roles in Jilin,while the human and cultural resources are important complementary parts as well .In the spatial distribu-tion analysis,the resources show the characteristic of “six clusters“and “three belts “spatial relations.Four clusters are centered on the cities,which are Changchum,Jilin,Baicheng,Tonghua and Jiˊan;one cluster is around the Changbai Moutains and one cluster nears the frontier at Tumen between China,Russia and P.D.R.Korea.And the three belts are;1)The west belt.It contains Xianghai and Momoge natural protection region.The evident of this zone is its ecologi-cal and ethical tourism resources.2)The middle belt characterized by urban traveling and recreation,including Jilin and Changchum,together with their nearby Nongˊan and Siping.3)The last belt is also the most important one,which is the east zone.It covers the Changbai Mountains,the golden triangles of Tonghua and the Tumen River.This zone is remark-able for its abundant natural landscapes and unique folk-customs.In the last part the concept planning is briefly construct-ed for the tourism resources in Jilin Province according to the above evaluation and analysis.  相似文献   

8.
在吉林省黑土区系统的野外调查和土壤及玉米籽实样品采集、测试的基础上,采用地球化学分析方法及SPSS技术,研究了Cd元素的土壤地球化学特征,及其在土壤和作物籽实中的含量特征和相关性,用以揭示Cd元素在土壤-作物系统中的转化累积特征及影响因素,为粮食安全服务。研究表明:吉林省黑土区Cd元素全量高于吉林省及全国土壤背景值,但不存在污染,籽实中Cd含量低于国家安全标准。土壤中Cd元素有效态转化程度较高,受其全量控制,同时Zn、 Cu及P元素有效量对Cd转化的作用明显,偏酸性土壤更利于Cd元素的转化。玉米籽实对Cd吸收程度较低,主要取决于其自身的生物特性, Zn元素缺乏可能导致玉米籽实对Cd元素吸收增加。  相似文献   

9.
The data on the coal production and consumption in Jilin Province for the last ten years were collected,and the Grey System GM( 1,1) model and unary linear regression model were applied to predict the coal consumption of Jilin Production in 2014 and 2015. Through calculation,the predictive value on the coal consumption of Jilin Province was attained,namely consumption of 2014 is 114. 84 × 106 t and of 2015 is 117. 98 ×106t,respectively. Analysis of error data indicated that the predicted accuracy of Grey System GM( 1,1) model on the coal consumption in Jilin Province improved 0. 21% in comparison to unary linear regression model.  相似文献   

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