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1.
利用树木车轮资料重建西藏中部过去气候的初步尝试   总被引:2,自引:0,他引:2  
为较可靠地利用年轮气候学方法重建过去气候,本文依据西藏中部,四个经过合适取样和精确定年的树木年轮年表,首先确立了它们各自生长状况对气候要素的响应函数,进一步明确年轮宽度与气候变化的关系。接着,选择可被重建的气候因子,并建立包括前期生长在内的、经过正交变换的转换函数,达到重建过去气温和降水的目的。此外,还划出不同的校准期和验证期,采用统计方法和其它类型代用资料进行检验。  相似文献   

2.
This is the third in a series of reports on Japanese geographic research prepared in cooperation with the Association of Japanese Geographers (AJG). Like the two previous reports, which appeared in the August and November issues, it has been modified for the English-speaking readership of THE PROFESSIONAL GEOGRAPHER. However, unlike the previous articles, each of which aimed at providing data regarding Japanese research on specific geographic topics, this paper is intended to supply the reader with an inventory of those materials that will be needed for the conduct of research in Japan. —H. Jesse Walker, Member, U.S. National Committee, IGU.  相似文献   

3.
A regret frequently expressed at International Geographical Congresses concerns the lack of summary information about the nature of geographic research in the host country. During a discussion of this point with members of the Association of Japanese Geographers, the idea of publishing a series of reports on various aspects of Japanese research surfaced. The concept was later enthusiastically supported by the United States National Committee for the International Geographical Union. This first report, “Historical Geography in Japan,” has been modified for the benefit of the English-speaking readers of THE PROFESSIONAL GEOGRAPHER. Although the reports will be of particular interest to those planning to attend the 1980 IGC in Tokyo, they should prove of general interest as well.—H. Jesse Walker, Member, U.S. National Committee, IGU.  相似文献   

4.
1991年,“海洋四号”科学考察船在南极布兰斯菲尔德海峡采集了大量的地球物理资料。本文在利用地震调查资料的基础上,根据现有的重力测量数据,研究引起重力异常的各种地质因素,对实测剖面重力异常进行正演拟合,建立了布兰斯菲尔德盆地的密度模型,并推导出该地区莫霍面深度-布格异常关系表达式,绘制出盆地的莫霍面深度图。  相似文献   

5.

This is the third in a series of reports on Japanese geographic research prepared in cooperation with the Association of Japanese Geographers (AJG). Like the two previous reports, which appeared in the August and November issues, it has been modified for the English-speaking readership of THE PROFESSIONAL GEOGRAPHER. However, unlike the previous articles, each of which aimed at providing data regarding Japanese research on specific geographic topics, this paper is intended to supply the reader with an inventory of those materials that will be needed for the conduct of research in Japan. —H. Jesse Walker, Member, U.S. National Committee, IGU.  相似文献   

6.
This is the second in a series of reports on Japanese geographic research prepared in cooperation with the Association of Japanese Geographers (AJG). Like the report on historical geography, which appeared in the August issue, this report on geomorphology has been modified for the English-speaking readership of THE PROFESSIONAL GEOGRAPHER. As an indication of the relative importance of geomorphology in Japanese geography, at the April 1979 annual meeting of the AJG in Tokyo 30 percent of the 138 papers presented were devoted to geomorphology.—H. Jesse Walker, Member, U.S. National Committee, IGU  相似文献   

7.
温家宝总理说过“土地是中华民族的生命线”,用地问题人们一直在密切关注着。江苏省在城镇化发展过程中已经积累了土地节约利用、优化布局等土地利用经验,但是目前江苏省在建设新农村背景下城镇发展过程中土地利用方面存在的小城镇建设用地秩序紊乱,园区建设规划不科学,基建用地量不断增加,征地成本偏低农民利益受损等一系列问题,由此提出创新优化调整园区建设用地,挖掘现有建设用地的空间,城镇化用地和农村用地相协调匹配,借用市场力量抑止土地浪费,清查整顿城镇发展而超标的土地等浅薄建议。  相似文献   

8.
沙坡头地区黄河阶地发育与地貌演化   总被引:5,自引:0,他引:5  
阎满存  董光荣 《中国沙漠》1997,17(4):369-376
沙坡头地区地处阿拉善地块、鄂尔多斯地块与祁连山褶皱带之间的一个复杂的边界带。青藏高原的隆升及其向东北的强烈挤压致使该区形成一系列向东北凸出的弧形挤压构造带,从而制约和影响了该区的地貌格局、演变和趋势。通过对沙坡头地区黄河阶地分布规律、地层结构、沉积相等的调查和研究,并结合室内年代测定、粒度和重矿物等分析,重建了沙坡头地区黄河演变的过程,讨论了黄河演变与沙漠形成发育的关系  相似文献   

9.

This is the second in a series of reports on Japanese geographic research prepared in cooperation with the Association of Japanese Geographers (AJG). Like the report on historical geography, which appeared in the August issue, this report on geomorphology has been modified for the English-speaking readership of THE PROFESSIONAL GEOGRAPHER. As an indication of the relative importance of geomorphology in Japanese geography, at the April 1979 annual meeting of the AJG in Tokyo 30 percent of the 138 papers presented were devoted to geomorphology.—H. Jesse Walker, Member, U.S. National Committee, IGU  相似文献   

10.
中国绿洲研究之进展   总被引:41,自引:2,他引:39  
韩德林 《地理科学》1999,19(4):313-319
绿洲是干旱区独具特色的生态景观。近10多年来,中国绿洲研究取得长足进展,在绿洲与绿洲系统、绿洲形成演变,绿洲的建设,调控与可持续发展等研究领域取得一批重要成果。要明确其研究对象与学科性质,紧紧围绕主要研究内容,进一步推动我 洲研究向更层次发展,愉占居国际前沿阵地。  相似文献   

11.
安徽省人居环境空间差异分析   总被引:5,自引:1,他引:5  
当今世界,随着城市化、工业化的高度发展,人们的生活水平不断提高,但一系列环境问题也随之出现并严重威胁着人类的健康和生存.人居环境的建设逐步成为学术界关注的焦点与重点领域之一.笔者选取安徽省13个城市,利用主成分分析和聚类分析的方法对安徽省的人居环境进行评价,建立了人居环境综合评价指标体系.经过分析,将13个城市分为4个类型,最后根据问题提出对策.  相似文献   

12.
苏州水网系列水质模型   总被引:1,自引:0,他引:1  
高维真 《地理学报》1989,44(1):47-56
为适应苏州水网水污染综合防治规划时进行水质预测的需要,本文提出苏州水网的非稳态系列水质模型,包括(1)网块水质模型,用于预测苏州网块水体水质年内(季节)变化;(2)分段水质模型,用于预测苏州城河逐段水质空间变化;(3)河网水质模型,用于预测苏州城河任一段面昼夜(逐时)水质变化。这些模型经过验证,获得满意的结果,并作了苏州水网的水质模拟和预测。  相似文献   

13.
香港的土地利用与环境保护   总被引:1,自引:0,他引:1  
陈朝辉 《热带地理》1997,17(2):149-156
香港地区地域狭小,地形崎岖,可利用地少,人口众多,用地紧张,但严谨的用地政策、规划用地和严格管地,使城镇有序,城乡结合协调,基础设施完善,做到合理用地,有效用地和高效用地,从而成为一座名副其实、整洁、美丽的现代化国际大都市。  相似文献   

14.
王强  么枕生 《地理学报》1990,45(3):363-372
本文从理论上推导了谱分析中最大后延M的取值,并且从理论和实际计算中得出了样本长度和其隐含周期之间的关系。只要抽样是平稳的,样本长度并非一定要求太长,仅略为超过其隐含周期的长度即可。但谱分析绝非是万能的。如果样本中仅含有两个波动,且当这两个波动的周期相差一个整数倍或更大时,这两个波动才可以通过谱分析分辨出,反之就会歪曲了其隐含周期。由此可见,在具体应用时,应作一些滤波和去掉趋势是必要的。因而这将对广大气象、地理科学工作者以及其它相邻学科的科研工作者具有重要的参考价值。  相似文献   

15.
云南气象台站迁址造成的气候"突变"分析   总被引:4,自引:0,他引:4  
气象观测资料是天气预报和气候变化分析的重要基础资料,观测环境的改变造成了资料的不连续。分析了云南元阳、西盟气象站因县城滑坡迁址引起的显著气候“突变”现象,从而导致云南两项气候极值记录的改变,引起了云南气候极值点的地理转移。采用Cramer、Yamamot和Mann-Kendall法检验了两站资料序列气候“突变”事实的存在。在短期气候预测、气候影响评价等业务中对两站资料的特殊性须做谨慎处理,采用短序列的新站址气候平均值更为重要。  相似文献   

16.
华薇娜  张洁  刘芳  邓三鸿 《极地研究》2009,21(2):124-140
通过美国的核心期刊数据库,收集了中国作者自1982年以来在世界核心期刊上所发表的有关南北极研究方面的文章,在此基础上进行了基本的文献计量学分析,包括各年文献量、期刊、著者、地区、机构、研究主题、引文等,以期从一个侧面来反映中国南北极研究方面的科研生产率、核心机构、核心人员、核心期刊、主要的研究领域、具有国际影响力的研究成果、发展趋势等信息,便于人们通过定量数据来了解中国南北极研究的现状、布局和实力。  相似文献   

17.
This paper argues for the incorporation of community environmental knowledge systems in modem land resource surveys. Such surveys, usually carried out by specialists from outside traditional communities, oftem do not incorporate the communities’ concepts and knowledge which modulate land use practices. They are therefore not helpful to the small farmers who are the primary land users. Recent studies have confirmed the viability of indigenous knowledge systems. In Swaziland, the farmers’ concepts of soil and slope unit systems have been validated and are found to be similar to the modem survey concepts of “soil series” and “land slope”. They have also employed other land attributes (such as animal life and vegetation elements) as indicators of land quality. The time has come when land resource surveys must take account of such indigenous knowledge systems so that the goals of improved land management and increased production may be achieved.  相似文献   

18.
嶂石岩地貌之发现及其旅游开发价值   总被引:29,自引:0,他引:29  
郭康 《地理学报》1992,47(5):461-471
本文在与有关地貌类型进行比较研究的基础上,提出了一种新型的地貌类型——峰石岩地貌,分析了它的特点、成因,研究了发育模式和形态分类,并对其景观旅游开发价值做了分析,给予较高的评价,认为它是一种重要的山岳型风景资源。目前已有多处被批准为国家级或省级风景名胜区,并取得显著的经济效益。  相似文献   

19.
The effect of peak shifts on the performance of a Kalman filter multicomponent analysis algorithm hasbeen investigated.A series of Gaussian test systems were employed to characterize the concentrationestimation errors and the morphology of the on-line residuals(the innovations sequence).Both forwardand reverse filters were used in the generation of the innovations sequences.It was found that thedifference between the forward and reverse innovations sequences gave an accurate indication of thedirection and magnitude of the peak shift.A series of overlapped two-component systems were alsoinvestigated.Again,a correlation between the difference innovations and the degree of the responseshift was observed.The behavior of the Katman filter in fitting the shifted fluorescence emissionspectrum of benzo[a]pyrene was also examined.The response for henzo[a]pyrene in cyclohexanesolution was compared to that obtained on the surface of a reversed phase thin layer chromatographyplate.A red shift of 4 nm was detected for the surface spectrum by observing the difference innovationssequence.This approach holds promise for correction of response shifts in multicomponent systems.  相似文献   

20.
刘慧屏 《热带地理》1998,18(3):279-285
中国地图科学工作者在继承和发扬祖国地图科学光辉传统的同时,吸取地球科学,空间技术和信息工程等学科的现代成就,使当代地图科学技术取得长足的进展,几十年来,航空摄影与系列制图,航天遥感与动态制图,计算机制图与电子地图,地理信息系统与制印一体化等先进科学技术已取得瞩目成绩,专题地图集的编制与信息时代相呼应,出现一些新观念,新技术,随着地球信息科学新学科的兴起,地图科学将出现新机遇,新挑战。  相似文献   

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