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991.
1 INTRODUCTIONAsanimportantcomponentoftheglobalterres trialecosystems ,forestlinkstheatmosphere ,soilandwatertogetherthroughitspowerfulecologicalfunc tion .Inrecentyears,owingtotheglobalwarmingandhumaninfluence ,forestfireoccurmuchmorefrequently .Theannualf… 相似文献
992.
1 BACKGROUND The Taihang Mountains is located in the western part of Hebei Province. It is bounded by the North China Plain to the east, the Shanxi Plateau to the west and the Yanshan Mountain to the north; the southern boundary is formed by the Huanghe (Yellow) River. It has an area about 30 000 km2, occupies about 17% of the total area of Hebei Province. The Taihang Mountains has a continental monsoon climate, with the mean annual temperature between - 1.7℃ to 13℃ and mean ann… 相似文献
993.
The Effect of Tide on the Global Climate Change 总被引:1,自引:0,他引:1
The differential rotation between the solid and fluid spheres caused by tidal force could explain the 1500 to 1800 - year cycle of the worlds temperature. Strong tide increases the vertical and horizontal mixing of water in the oceans,dra-wing the cold Pacific water from the depths to the surface and the warm water from the west to the east, where it cools or warms the atmosphere above, absorbs or releases CO2 to decrease or increase greenhouse effect and to make La Nina or El Nino occur in the global.
The moons declination and obliquity of the ecliptic affect the tidal intensity. The exchange of tidal energy and tide -generating force caused by the sun, moon and major planets makes the earths layers rotate in different speeds. The differenti-al rotation between solid and fluid of the earth is the basic reason for El Nino and global climate change. 相似文献
994.
Thehumandevelopmentalhistoryrevealsthatmanhasneverneglected exploitingtheundergroundspace, fromtheprimitive'caveliving' tothe'undergroundvillage' inMatermataofTunis,fromthesubsided'cavedwelling' inthenorthwestofChinatothepre-sent'undergroundcity'.Theundergroundspacehasbeenexploitedwidelyanddeeply. Thewidespreadutilization oftheurbanunder-groundspacetookplaceafter thebeginningofindus-trialrevolutionsandurbanization.Dueto seriesofproblemsonurbandevelopmentresultedfromtheoverconcentrationofpo… 相似文献
995.
1OVERFLOWBURSTOFMORAINELAKEFloodwater and debris flow caused by glacial lake burst is an important land process and a serious moun-tain disaster in glacial area. Glacial lakes with burst can divided into the glacier-obstructed lake (ice dam lake) and the terminal moraine lake (XU and FENG, 1988). Typical burst of ice dam lake happens in the modern glacier area of the upper reaches of the Kele-qing River in Uygur Autonomous Region of Xinjiang (WANG, 1990). But most of burst gla… 相似文献
996.
WANG Yingbin LIU Qun* and WANG Yanjun College of Fisheries Ocean University of China Qingdao P. R. China 《中国海洋大学学报(英文版)》2007,6(1):53-59
1 Introduction Natural mortality coefficient (M) is one of the key population parameters common to most analyses in fish stock assessment. Many mathematical models of fish stock dynamics include M directly or indirectly. However, until now M is the least known among the four factors affecting fish stock variation: recruitment, growth, natural death and fishing death (Quinn and Deriso, 1999). There is an extensive literature concerning the impact of errors in M on stock assessment (Mertz and… 相似文献
997.
FANG Mingqiang) ) and QU Liqin) )) Ocean Remote Sensing Institute Ocean University of China Qingdao P. R. China ) The Key Laboratory of Ocean Remote Sensing Ministry of Education P. R. China 《中国海洋大学学报(英文版)》2007,(4)
The Sea Level Anomaly-Torque (SLAT, relative to a reference location in the Pacific Ocean), which means the total torque of the gravity forces of sea waters with depths equal to the Sea Level Anomaly (SLA) in the tropical Pacific Ocean, is defined in this study. The time series of the SLAT from merged altimeter data (1993-2003) had a great meridional variation during the 1997-1998 El Nio event. By using historical upper layer temperature data (1955-2003) for the tropical Pacific Ocean, the tempera- ture-based SLAT is also calculated and the meridional variation can be found in the historical El Nio events (1955-2003), which suggests that the meridional shifts of the sea level anomaly are also intrinsic oscillating modes of the El Nio cycles like the zonal shifts. 相似文献
998.
I INTRODUCTIONThe second longest river in China is the Huanghe(Yellow) River on the north of Mt Bayankala on theQinghai-Xizang (Tibet) Plateau. It winds its way through Qinghai, Sichuan, Gansu, Ningxia, Inner Mongolia, Shanxi, Shaanxi, Henan, Shandong, and emptiesinto the Bobal Sea at Kenli County of ShandongProvince. It has a total length of 5464km with adrainage area of 752 443km2. The rushing currentsfrom Longyangxia Gorge to Qingtongxia Gorge in itsupper reaches, running g… 相似文献
999.
Manzhouli, a city of Halun Buir, is located at 117°12, -- 1 17"53'E, 49"19, -- 49o41'N with a total area18. 73km2. Its morphologies are mainly hills andsloping fields and the average height above sea level is654m. It is rounded by the hills and higher in the southpart and lower in the north part. It'S climate is thesemi-dry climate of mid-temperate zone with the coldand windy winter and cool and short summer. It is dryin spring and the temperature decreases quickly in theautumn with the ear… 相似文献
1000.
1 INTRODUCTION The Changjiang (Yangtze) Delta and its neighboring regions mentioned in this article is located in the lower reaches of the Changjiang River, whose north, east, south and west adjacent places are Xingtongyang Canal, Huanghai Sea, East China Sea, Qiantang River, Hangzhou Bay and Nanjing, Zhenjiang respectively. These regions belong to Jiangsu Province, Zhejiang Province and Shanghai City in administrative division, being one of the economic developed regions. The … 相似文献