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471.
DISTRIBUTIVETENDENCYOFELEMENTCONCENTRATIONSINLIMESTONESOILSINEASTERNCHINAWenYanmao(温琰茂);ZengShuiquan(曾水泉);PanShurong(潘树荣);Luo... 相似文献
472.
PROBLEMSOFTHEAQUATICENVIRONMENTANDCOUNTERMEASURESINRAPIDECONOMICDEVELOPMENTINTHEZHUJIANGRIVERDELTA¥WenYanmao(温琰茂);ChengGuopei... 相似文献
473.
关于地理环境的理解和运用问题 总被引:1,自引:0,他引:1
管文 《云南地理环境研究》1991,3(1):58-65
本文借助语言、逻辑知识,从“偏正结构”、“相关词义”、“派生概念”三方面,阐明了地理环境的确切含义和实际运用问题。笔者在分析、探讨地理环境问题时,提出了一些与当今辞书和重要著述相悖的定义。作者认为,长期以来,围绕地理环境及其派生概念“决定论”所开展的一切无端之争,除立场、观点和历史局限外,无不与下列问题的认识、理解不一有关:关于历史与现代决定论问题;关于决定与决定论问题;关于内外环境决定论问题。 相似文献
474.
The genetic diversity of both wild and reared Pseudosciaena crocea (Richardson) col-lected from Guan-Jing-Yang in Ningde, China in May 1999 was investigated by random amplified poly-morphic DNA (RAPD) in the present study. The polymorphism and mean difference of the wild popula-tion as revealed by RAPD were 18.9% and 0.0960 respectively, and those of the reared stocks were rel-atively lower, with 16.7% in polymorphism and 0.0747 in mean difference. The genetic distance be-tween the two stocks was 0.0041. From the comprehensive investigation, the main reasons for the loss of genetic diversity were probably overilshing, small number of parents as broodstocks and the debatable arti-ficial ranching. Results from this study also showed that the large yellow croaker populations distributed along Fujian coastal waters including Guan-Jing-Yang still potentially wide genetic variability. It is sug-gested that genetic management and prevention should be scientifically conducted in order to maintain and improve the genetic diversity of the P. crocea population. 相似文献
475.
A preliminary application GIS in glaciological research along the traverse route from Zhongshan Station to Dome A, Antarctica 总被引:1,自引:0,他引:1
1 IntroductionGeographicalinformationsystem (GIS)isanefficientwayandimportanttechniquetomanage,displayandanalyzeAntarcticspatialdata.GIScanbeusedtomakeandre newmapproductsquickly ,evaluateenvironment,supportlogisticmanagementandfieldoperation,providechancetoextractnewknowledge,andtopromoteinformationex changeamongnationsunderthedemandoftheMadridProtocol(AADC 2 0 0 1 ;MAGIC1 998;1 999) .WorkingGroupofGeodesyandGeographicInformation (WG GGI)ofScientificCommitteeonAntarcticResearch (… 相似文献
476.
Wu Chaoyuan Li Jiajun Xia Enzhan Peng Zhuosheng Tan Shuzhi Li Jun Wen Zongcun Huang Xiaohang Cai Zulin Chen Guojun 《中国海洋湖沼学报》1989,7(4):327-334
A 2-year study onKappaphycus alvarezii (Doty) Doty introduced to Hainan Island from the Philippines in 1985 showed promising results. The average daily growth in
weight reached 10% at a favourable temperature of about 26°C. Experimental results showed that timely cutting of the plant
was an effective way to obtain new cuttings for cultivation and accelerate growth. New cuttings 0.05 kg in weight are suggested
to be used as “seeds” and the old plant should be harvested. At present, artificial cultivation with a type of underwater
raft applicable in places where there is strong wind will expand cultivation to more regions in Hainan Province.
This paper was originally published in Chinese inOceanologia et Limnologia Sinica
19(5): 410–418, 1988. The plant under discussion wasEucheuma alvarezii Doty which was previously calledE. striatum in the article, and which now becomesKappaphycus alvarezii (Doty) Doty. To the original title, “in China” was added. Only the essence of the original article was presented. 相似文献
477.
Average slip rate,earthquake rupturing segmentation and recurrence behavior on the Litang fault zone,western Sichuan Province,China 总被引:3,自引:0,他引:3
XU Xiwei WEN Xueze YU Guihua ZHENG Rongzhang LUO Haiyuan & ZHENG Bin . Institute of Geology China Earthquake Administration Beijing China . Earthquake Administration of Sichuan Province Chengdu China 《中国科学D辑(英文版)》2005,48(8):1183-1196
The Litang fault zone (LFZ) is an important active fault within the northwestern Sichuan sub-block. To-gether with the Garzê-Yushu, Xianshuihe, and An-ninghe fault zones on its northern, eastern and south-eastern sides, the LFZ constitutes the lateral extrusion tectonic system in the southeastern part of the Qing-hai-Tibetan Plateau[1,2] (Fig. 1). According to instru-mental records, historical recordings and field investi- gation, an earthquake (Ms7.3) occurred on its middle to south se… 相似文献
478.
WEN Lingjuan LU Huayu & QIANG Xiaoke State Key Laboratory of Loess Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China 《中国科学D辑(英文版)》2005,48(9):1452-1462
In recent years, the Red Clay deposits underlying Quaternary loess on the Chinese Loess Plateau (north China) have attracted more attention because they show a direct and continuous record of past atmos- pheric circulation and palaeoclimatic change. Investiga- tions on Red Clay deposits through multidisciplinary methods have demonstrated an aeolian origin for the Red Clay, like the overlying Quaternary loess. The Red Clay formed during the Miocene and Pliocene[1―13]. However, the type o… 相似文献
479.
Perspectives on Chinese ground water resources 总被引:1,自引:0,他引:1
480.
本文提出了我国核电发展的 4项策略 ,明确了近中远兼顾的 3个层次的发展目标及相关的重点工程。 相似文献