检索结果-南通市图书馆

Journal of Mountain Science 2004年第3期1卷 239-249页

作者： ZHOUYue LUXixi HUANGYing ZHUYunmei FacultyofEnvironmentalScienceandEngineering KunmingUniversityofScienceandTechnologyKunming650093China departmentofgeography UniversityofSingapore10KentRidgeCrescent119260Singapore BureauofHydrologyandWaterResourcesofYunnanProvince Kunming650093China

The sediment flux data, measured from a dry-hot valley of the Longchuan River, a tributary of the lower Jinsha River, were analyzed with Mann-Kendall test, Seasonal Mann-Kendall test and Sen’s test. In both the upper reaches (Xiaohekou) and the lower reaches (Xiaohuangguayuan), the sediment fluxes showed a significant increase from 1970 to 2001, despite the fact that the water discharge did not change significantly during the period and numerous reservoir constructions which contribute to the trap of sediment. This can be attributed to the intensification of human activities, especially the activities related to land surface disturbances such as deforestation and afforestation, expansion of agriculture land, and road constructions. This increase is more significant in the lower reaches of the river observed at the place of Xiaohuangguayuan due to the dry-hot climate. The profound increase in sediment flux has significant implications for effective management of the sedimentation problems of the on-going Three Gorges Reservoir.

关键词： Sediment flux dry-hot valley deforestation afforestation reservoir road construction

An Application of Dynamic Structure Model to SoilCorrosion Research

在线全文

学校读者我要写书评

暂无评论

Systems Science and Systems Engineering 1999年第1期9卷 90-95页

作者： ZHAO Bingdong GUAN Hua(department of geography,Hen an university, Kaifeng 475001, China)

Soil corrosion is a complex system which is difficult to be simulated with mathematicalmodels. Taking the mountainous areas in western henan Province as an example, this paper describesthe application of dynamic structure model to soil corrosion analysis. The primary component factors ofthe soil corrosion system and the causality of the factors are determined in this paper. The interactiverelations of the systematic variables is established with delphi method. The dynamic structure modelis selected to make the forecast of the soil corrosion system, the analysis of sensitivity of the variablesand the analysis of the system control.

关键词： mountainous areas in western henan province dynamic structure model soil corrosion system forecast

On the modes of urban-rural networking development in China

在线全文

学校读者我要写书评

暂无评论

Journal of Geographical Sciences 2000年第4期10卷 37-44页

作者： ZENG Ju-xin (department of geography, Huazhong Normal university, Wuhan 430079, China)

This essay tries to reveal the developmental regularity of urban-rural networking manifested by urbanization. The urban-rural networking is a reality and an inexorable trend of development. As a physical existence, the urban-rural networking reflects a result of the interaction between cities and rural areas; it is a necessary and sufficient condition for sustaining progress of cities and rural areas. As an objective developmental tendency, it reflects an urban-rural regional economic process. The author briefly analyzes two contradictory urban-rural developmental views, and puts forward a concept of the mode of urban-rural networking development. The author also analyzes the mode from the perspectives of economics and philosophy.

关键词： urban-rural areas networking development model

Gradient analysis of landscape spatial and temporal pattern changes in Beijing metropolitan area

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2010年第S1期53卷 91-98页

作者： YANG YeTao1,ZHOU QiMing2,GONG JianYa3 & WANG YingYing4 1 Institute of Geophysics and Geomatics,China university of Geosciences,Wuhan 430074,China 2 department of geography,Hong Kong Baptist university,Hong Kong 3 State Key Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan university,Wuhan 430074,China 4 Hubei Provincial Bureau of Meteorology,Wuhan 430074,China Institute of Geophysics and Geomatics China University of Geosciences Wuhan China department of geography Hong Kong Baptist University Hong Kong China State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan China Hubei Provincial Bureau of Meteorology Wuhan China

The gradient based landscape metrics analysis is now widely used to study the landscape pattern changes in respond to the *** order to discover the trend of spatio-temporal changes in Beijing metropolitan area during the past 15 years,several landscape metrics are computed using a moving window along a 96 km long transect across Beijing metropolitan area from west to ***,the spatial extent of sub-landscape,which is determined by the moving window’s size,is profoundly *** results show that the metrics varies smoothly and regularly along the selected transect when the window size is greater than 6 km×6 km,and irregularly fluctuated for the smaller window size,that the spatial and temporal landscape characteristics of Beijing city match the hypothetical framework of spatio-temporal urban sprawl in the form of alternating processes of diffusion and coalescence well,and that some new trends of the urban sprawl style in Beijing metropolitan area,such as leap-frog manner,are also detected by the gradient landscape analysis.

关键词： gradient analysis landscape metrics spatio-temporal urban expansion multi-extent

Formation and Evolution of Ancient Lakes on South Coast Plain of Laizhou Bay

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Population,Resources and Environment 2005年第4期3卷 26-32页

作者： Han Mei 1, Zhou Baohua 2, Yang Peilin 1,Gao Guiqin 1 & Zhang Weiying 1 1. department of geography, Shandong Normal university, Jinan 250014, China 2. department of geography, Jinan university, Jinan 250001, China department of geography Shandong Normal University Jinan 250014 China department of geography Jlnan University Jinan 250001 China

Based on the data of historical geography, the analysis of the stratigraphic section, and the textual research of place names and satellite photographic interpretations, the authors study the formation and evolution of ancient lakes on the south coast plain of Laizhou Bay where there were once three lakes: Judian Lake, Qingshuibo Lake and Biehua Lake. All the lakes formed 6000 years ago evolved from the lagoons near the estuary and went through two periods, the golden age in the Middle Holocene and the shrinking age in the Late Holocene. The disappearance of the lakes resulted from the drying climate, the migration of the river courses and the activities of human beings. Among the three reasons, the migration of the river courses is the main one.

关键词： ancient lake cause historical evolution south coast plain of Laizhou Bay

ECOLOGICAL AND SOCIO-ECONOMIC REHABILITATION IN THE KARST OF SOUTHWEST CHINA

在线全文

学校读者我要写书评

暂无评论

Journal of Geographical Sciences 1997年第2期7卷 24-32页

作者： Cai Yunlong department of geography, Peking university, Beijing 100871 People’s Republic of China

The Karst of Southwest China is a typical representative of poverty stricken region with impoverishment-degradation spiral. To essentially break away from this vicious circle, the local ecology, economy and society should be rehabilitated, and hence to strengthen the self-development capacity building of the localities. Two considerations are stressed in this article: (1) Poverty alleviation is a system project with great complexities. Any single approach is difficult to success and integrated measures should be taken. (2) Some typical and feasible areas should be selected to demonstrate the project of poverty alleviation and ecological, socio-economic reconstruction. Then, they can be used as a model to promote the sustainable development of the whole region. Based upon these ideals, a project entitled “Reversal of Impoverishment-Degradation Spiral in the Karst of Southwest China' was proposed and has been listed in 《Priority Programme for China's Agenda 21》.

关键词： poverty alleviation environmental degradation capacity building ecological and socio-economic rehabilitation karst areas Southwest China.

Study of evolution forecast of the area of the Huanghe River mouth

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 1993年第2期12卷 249-259页

作者： Guo Yongsheng, Xu Xuegong, Fan Zhaomu, Wu Peihong and Zhu Xiaoge department of geography, Shandong Normal university, Jinan 250014, China department of geography, Peking university, Beijing 100871, China Remote Sensing Geology department, Oil Exploration and Exploitation Scientific Research Institute, Beijing 100083, China China

From 1979 to 1989, the current Qingshuigou course of the Huanghe River formed a sub - delta which resembles a beak extending into the Laizhou Bay. It covers 618 km2 in area. To meet the needs of developing and constructing the Huanghe River Delta and under the presupposition of keeping the current course for 15-20 a, we forecast mainly by using the OM (1, 1) model that the front border of the sub-delta will be close to 119°30'E and its area will become 923 km2by the end of the year 2000. The Huanghe River will make land 760 km2 in area.

关键词： Huanghe River mouth Markov chain forecasting method of grey number series

CHINA: A COUNTRY OF THE THIRD WORLD OR THE THIRD GREAT POWER?

在线全文

学校读者我要写书评

暂无评论

Journal of Geographical Sciences 1996年第3期6卷 84-88页

作者： Hu Zhaoliang(department of geography, Peking university, Beijing 100871People’s Republic of China)Soon-Cheol MoonSeoul national university, Seoul, Korea

In 1990, World Bank and IMF calculated China's GDP with Purchasing Power Parity (PPP). World Bank estimated it at 1,950 U.S dollars and IMF did it at 1,300. According to this figure, China ranked next to U.S. and Japan in the world. This result has created a dispute whether China is a country of the Third World or the third great power. For explaining this question, measuring system of the PPP and traditional exchange rate must be exanined first.

关键词： third world economic growth GDP China

Cav1.2,Cav1.3,and Cav2.1 in the mouse hippocampus during and after pilocarpine-induced status epilepticus

在线全文

学校读者我要写书评

暂无评论

Cav1.2,Cav1.3,and Cav2.1 in the mouse hippocampus during and...

An insight into understanding the control of cell proliferation by GA in Arabidopsis

中国神经科学学会第四次会员代表大会暨第七届全国学术会议

作者： Jie H.XU~1,Li LONG~3,Yong C.TANG~2,Hai T.HU~1,Feng R.TANG~(1,2,4) 1 department of Anatomy and Histology,School of Medicine,Xi''an Jiaotong university,Xi''an 710061,China 2 Epilepsy Research Laboratory,national Neuroscience Institute,singapore 3 department of Cell Biology and Genetics,Kunming Medical College,Kunming 650031,China 4department of Anatomy,national university of singapore,singapore

＜正＞Calcium binding proteins are well known to be expressed by different groups of hippocampal intemeurons;however,whether voltage-dependent calcium channels（Cav） are also localized in these neurons,changed during and after status epilepticus（SE）,and involved in epileptic activity have not been *** the present study,we showed the colocalization of three subtypes of voltage-gated calcium channels（Cav1.2,Cav1.3,or Cav2.1） with different calcium binding proteins such as calbindin（CB）,calretinin（CR）,and parvalbumin（PV）.At early stages during and after pilocarpine -induced status epilepticus（PISE）,significant changes of expression of Cav 1.2,Cav 1.3（L-type）,and Cav2.1（P/Q-type） were found in different groups of hippocampal *** expression of Cav 1.3 or Cav2.1 in reactive astrocytes was shown at 1 week and 2 months after *** the latter time point,higher percentages of colocalization of PV and Cav1.2,CB,or PV and Cav1.3 or Cav2.1,lower percentages of CR and Cav 1.3 or Cav2.1 immunoposivie neurons were observed in gliotic CAl *** therefore conclude that voltage-gated calcium channels are expressed by different groups of hippocampal intemeurons in the *** acute stages during and after PISE,up- or down-regulation of Cav1.2,Cav1.3,or Cav2.1 in functionally different groups of intemeurons in CA1 area may be related to the changes of their ***-regulation of Cav 1.2,Cav 1.3,or Cav2.1 in granule cells may be directly related to the occurrence of SE. The induced expression of Cavl.3 or Cav2.1 in reactive astrocytes at 1 week and 2 months after PISE suggests that Cav1.3 or Cav2.1-related calcium signaling in reactive astrocytes may be involved in initiation,maintenance or spread of seizure *** gliotic CA1 area at chronic stage（i.e.,2 months after PISE）,the occurrence of higher percentages of colocalization of PV and Cav1.2,CB,or PV and Cav1.3 or Cav2.1,lower percentages of CR and Cav1.3 or Cav2.1 immunopositive neurons may suggest tha

关键词： calcium channels intemeurons astrocytes hippocampus epilepsy

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

An insight into understanding the control of cell proliferat...