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1.
《东北亚地学研究》2006,9(1):I0001-I0001
The journal of Global Geology （English Edition ） edited by the International Center of Geoscience Research and Education in Northeast Asia （ICGRENEA） with the headquarters in Jilin University of China, is formally issued today. The former name of the journal was the Journal of International Geoscientific Research in Northeast Asia which was started in 1998 and served the scientists and teachers in Geoscience in the world, but mainly for the scientists from the six countries of the NE Asia including China, DPR Korea, Japan, Korea, Mongolia and Russia. 相似文献
2.
Lasafam Iturrizaga 《山地科学学报》2008,5(1):1-16
The Kvíárjokull,a southern outlet glacier of the Vatnajokull,is confined in the mountain foreland by lateral moraines measuring a height of up to 150 m. Each of the lateral moraines shows considerable breaches with deviations of the main moraine ridges. The paper discusses the possible origins of these modifications of the lateral moraines as result of： 1） ice overlappings during glacier advances and subsequent breaches of the lateral moraine,2） bifurcations of the Kvíárjokull glacier tongue triggered by the preglacial relief conditions and the prehistorical moraine landscape leading to afflux conditions,3） drainage of ice-marginal glacier lakes and 4. volcanic activities,such as lava flows and volcanic-induced jokulhlaups. A historic-genetic model of the formation of the lateral moraines is presented considering the breaches in the lateral moraines as result from glacier bifurcations and therefore as former tributary tongue basins. Such breaches in the lateral moraines are also common landscape features at glaciers outside of Iceland and are from wider importance for the paleoreconstruction of former glacier stages. The knowledge of their development is essential for an adequate relative age classification of individual moraine ridges. In regard to the origin of the debris supply areas of the large-sized Kvíárjokull moraines,the resedimentation of prehistoric till deposits by younger glacier advances plays a role in the formation of the lateral moraines apart from englacial and supraglacial sediment transfer processes. 相似文献
3.
Micromorphology of landslide soil——Case study on the Jibazi landslide in Yunyang in the Three Gorges Region, China 总被引：2，自引：1，他引：1
HE Yurong CUI Peng LIAO Chaolin ZHANG Baohua ZHAO Yu 《山地科学学报》2006,3(2):147-157
Introduction The studies on landslides in the Three Gorges Region were conducted, e.g., those on affecting factors and forming mechanism of landslide (YIN Kunlong et al. 1998, DENG Qinglu et al. 2000, CHEN Yongbo et al. 2003, XU Qiang et al. 2003), on ris… 相似文献
4.
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5.
Spatial Pattern of Rural Settlements in the Upper Reaches of the Minjiang River——a Case Study in Maoxian County, Sichuan 总被引：1，自引：1，他引：0
FENG Wenlan LI Ainong Chengdu Institute of Mountain Hazards Environment Chinese Academy of Sciences Chengdu Sichuan China Graduate School of Chinese Academy of Sciences Beijing China 《山地科学学报》2007,4(2):146-154
A quantitative analysis of the spatial pattern of rural settlements in the upper reaches of the Minjiang River was made with the major data sources being the relevant ETM image and the national geographical database of China (including contour line, river and road) at the scale of 1:250 000, and using image interpretation and field investigation to obtain spatial information on rural settlements. The results of the spatial analysis technique of GIS and correlation analysis showed that most settlements (78.2 %) were located in the mountain area at 1500 ~ 2700 m altitude, and almost half in the arid valley area. More than 80.0 % of settlements had their slopes above 15°. Most settlements had good access to water resources, roads and communications, and tended to cluster close to the road network rather than the river. About half of the rural settlements in the study area were relatively concentrated, while the others were decentralized. Those with higher altitude usually had land with steep slope, inconvenient water and road accesses, and were located far apart from each other. In view of such a situation, further research should be done to make reasonablecountermeasures on these settlements for better living conditions and ecosystem stability. 相似文献
6.
《中国海洋大学学报(英文版)》2021,(5)
The global monsoon(GM) comprises two major modes, namely, the solstitial mode and equinoctial asymmetric mode.In this paper, we extend the GM domain from the tropics to the global region and name it the global spring – autumn monsoon(GSAM), which mainly indicates a spring–autumn asymmetrical precipitation pattern exhibiting annual variation. Its distribution and possible formation mechanisms are also analyzed. The GSAM domain is mainly distributed over oceans, located both in the midlatitude and tropical regions of the Pacific and Atlantic. In the GSAM domains of both the Northern and Southern Hemispheres, more precipitation occurs in local autumn than in local spring. The formation mechanisms of GSAM precipitation vary according to the different domains. GSAM precipitation in the tropical domain of the Eastern Hemisphere is influenced by the circulation differences between the onset and retreat periods of the Asian summer monsoon, while tropical cyclone activities cause precipitation over the South China Sea(SCS) and western North Pacific(WNP). GSAM precipitation in the tropical domain of the Western Hemisphere is influenced by the tropical asymmetrical circulation between the Northern and Southern Hemispheres and the variation in the intertropical convergence zone(ITCZ) driven by the intensity of the sea surface temperature cold tongues over the equatorial eastern Pacific and eastern Atlantic. GSAM precipitation in the midlatitude domain is influenced by the differences in water vapor transportation and convergence between spring and autumn. In addition, GSAM precipitation is also affected by extratropical cyclone activities. 相似文献
7.
To solve nutrient flux and budget among waters with distinct salinity difference for water-saltnutrient budget,a traditional method is to build a stoichiometrically linked steady state model.However,the traditional way cannot cope appropriately with those without distinct salinity difference that parallel to coastline or in a complex current system,as the results would be highly affected by box division in time and space,such as the Changjiang(Yangtze) River estuary(CRE) and adjacent waters(30.75°-31.75°N,122°10′-123°20′E).Therefore,we developed a hydrodynamic box model based on the traditional way and the regional oceanic modeling system model(ROMS).Using data from four cruises in 2005,horizontal,vertical and boundary nutrient fluxes were calculated in the hydrodynamic box model,in which flux fields and the major controlling factors were studied.Results show that the nutrient flux varied greatly in season and space.Water flux outweighs the nutrient concentration in horizontal flux,and upwelling flux outweighs upward diffusion flux in vertical direction(upwelling flux and upward diffusion flux regions overlap largely all the year).Vertical flux in spring and summer are much greater than that in autumn and winter.The maximum vertical flux for DIP(dissolved inorganic phosphate) occurs in summer.Additional to the fluxes of the Changjiang River discharge,coastal currents,the Taiwan Warm Current,and the upwelling,nutrient flux inflow from the southern Yellow Sea and outflow southward are found crucial to nutrient budgets of the study area.Horizontal nutrient flux is controlled by physical dilution and confined to coastal waters with a little into the open seas.The study area acts as a conveyer transferring nutrients from the Yellow Sea to the East China Sea in the whole year.In addition,vertical nutrient flux in spring and summer is a main source of DIP.Therefore,the hydrodynamic ROMS-based box model is superior to the traditional one in estimating nutrient fluxes in a complicated hydrodynamic current system and provides a modified box model approach to material flux research. 相似文献
8.
SHI Xueli 《中国海洋大学学报(英文版)》2009,8(2)
In this study,the effects of ‘initial’ soil moisture(SM) in arid and semi-arid Northwestern China on subsequent climate were investigated with a regional climate model. Besides the control simulations(denoted as CTL),a series of sensitivity experiments were conducted,including the DRY and WET experiments,in which the simulated ‘initial’ SM over the region 30 –50°N,75 –105°E was only 5% and 50%,and up to 150% and 200% of the simulated value in the CTL,respectively. The results show that SM change can modify ... 相似文献
9.
VishwambharPrasadSati 《山地科学学报》2004,1(2):155-165
Agrarian system is well adapted in Himalayan eco-system. Hence, the people have adopted the traditional subsistence cereal farming and it becomes the main stay of Himalayan people. About 80 percent of the workable force is attached with agriculture and its allied practices, according to the census of 1991. Although, horticultural farming runs parallel with agriculture, its proportion in terms of land is quite less, resulted in a negligible place in the economy of the region. Human resources, mainly men are attached with national security after recruitment in Army. While, women play a vital and integrated role in maintaining the workable potential in the field of agriculture and are known as backbone of economy. An animal resource implies foremost and wider part in agricultural system and economy as well Water resources are unutilized yet, while almost all the major rivers of our country are originated from and flowing through this region. Increasing population causes forest resources depletion. The economy of the region is rested either on ‘traditional cereal farming‘ or ‘money order based‘ development, which could not take place due to its remoteness from the main streams of the country. The impactof modern technology with innovation in agricultural system remains impracticable due to unwillingness of people in one hand and on the other hand, adversege ographical conditions like topography, climate etc. which could not permit the uses of modern innovation in the field of agriculture. As for infra-structurally, this region is lacked behind, due to its inaccessibility. While, this region is bestowed with numerous rivers, many places for tourists and pilgrims, and huge forest resources. They might be used evenly in thedevelopment processes. The practice of tourism will help for the further development, particularly, in the wake of the newly born state, Uttaranchal. The present paper aims to evaluate the present potentiality of resources and their balanced utilization in the Pindar Basin. A precise study has been done on resource utilization, ecology and environment with keeping view in mind that more or less exploitation of resources could not influence the environment and the economy of the region. 相似文献
10.
《中国海洋湖沼学报》2017,(6)
The coastal zone is an area characterized by intense interaction between land and sea, high sensitivity to regional environmental changes, and concentrated human activities. Little research has investigated vegetation cover changes in coastal zones resulting from climate change and land-use change, with a lack of knowledge about the driving mechanism. Normalized diff erence vegetation index(NDVI) can be used as an indicator for change of the coastal environment. In this study, we analyzed the interannual changes and spatial distribution of NDVI in the coastal zone around Jiaozhou Bay in Qingdao, a coastal city undergoing rapid urbanization in northeast China. The underlying causes of NDVI variations were discussed in the context of climate change and land-use change. Results showed that the spatio-temporal distribution of NDVI displayed high spatial variability in the study area and showed a typical trend of gradually increasing from coastal to inland regions. The significant increase area of NDVI was mainly found in newly added construction land, extending along the coastline towards the inland. Land vegetation cover demonstrated a certain response relationship to sea-land climate change and land-based activities. The impact of land-based human activities was slightly greater than that of sea-land climate change for land vegetation cover. The results indicate that promoting ecological policies can build an ecological security framework of vegetation suitable for the resource characteristics of coastal cities. The framework will buf fer the negative ef fects of sea-land climate change and land-based human activities on vegetation cover and thereby achieve the balance of regional development and ecological benefits in the coastal zone. 相似文献
11.
Cyanobacteria are oxygenic photosynthetic Gram-negative bacteria that can form potentially toxic blooms in eutrophic and slow flowing aquatic ecosystems. Bloom toxicity varies spatially and temporally, but understanding the mechanisms that drive these changes remains largely a mystery. Changes in bloom toxicity may result from changes in intracellular toxin pool sizes of cyanotoxins with differing molecular toxicities, and/or from changes in the cell concentrations of toxic and non-toxic cyanobacterial species or strains within bloom populations. We show here how first-order rate kinetics at the cellular level can be used to explain how environmental conditions drive changes in bloom toxicity at the ecological level. First order rate constants can be calculated for changes in cell concentration( μ_c : specific cell division rate) or the volumetric biomass concentration( μ_g : specific growth rate) between short time intervals throughout the cell cycle. Similar first order rate constants can be calculated for changes in nett volumetric cyanotoxin concentration( μ_(tox) : specific cyanotoxin production rate) over similar time intervals. How μ_c(or μ_g) covaries with μ tox over the cell cycle shows conclusively when cyanotoxins are being produced and metabolised, and how the toxicity of cells change in response to environment stressors. When μ_(tox)/μ_c 1, cyanotoxin cell quotas increase and individual cells become more toxic because the nett cyanotoxin production rate is higher than the cell division rate. When μ_(tox)/μ_c =1, cell cyanotoxin quotas remains fixed because the nett cyanotoxin production rate matches the cell division rate. When μ_(tox)/μ_c 1, the cyanotoxin cell quota decreases because either the nett cyanotoxin production rate is lower than the cell division rate, or metabolic breakdown and/or secretion of cyanotoxins is occurring. These fundamental equations describe cyanotoxin metabolism dynamics at the cellular level and provide the necessary physiological background to understand how environmental stressors drive changes in bloom toxicity. 相似文献
12.
The seasonal fluctuation of the plasmodia ofMyxobolus gibelioi Wu et Wang, 1982 in the gill filaments of the allogynogenetic gibel carpCarassius auratus gibelio (Bloch) in a fish pond in Hubei Province of China was investigated from August 1999 to July 2000. A total of 445 fish was
examined; the overall prevalence of the plasmodium infection in the fish was 64.94% and mean abundance of plasmodia was 11.65±27.85
(mean±SD). Significant seasonal changes in prevalence and mean abundance, with higher levels of the plasmodia infection from
late spring to autumn, were observed.
This research was financially supported by the Projects for Knowledge Innovation of the Chinese Academy of Sciences (No. KSCX2-1-04
and No. 1999051) and the Science & Technology Commision of Wuhan City (No. 995004095G). 相似文献
13.
As a National Basic Research Program (973 Program) of China, the Key Processes, Mechanism and Ecological Consequences of Jellyfish Bloom in China Coastal Waters led by Prof.SUN Song
from Institute of Oceanology, Chinese Academy of Sciences (IOCAS) was endorsed by the Ministry of Science and Technology.Recently, the kick-off meeting of this five-year (2011-2015)
program was held on January 15-16 in Qingdao,China.More than 120 participants attended the meeting. 相似文献
14.
WANG Weiwu College of civil engineering architecture Zijinggang Campus Zhejiang University Hangzhou China 《山地科学学报》2007,(3)
In China,many scenic and tourism areas are suffering from the urbanization that results from physical development of tourism projects,leading to the removal of the vegetative cover,the creation of areas impermeable to water,in-stream modifications,and other problems. In this paper,the risk of soil erosion and its ecological risks in the West Lake Scenic Spots (WLSS) area were quantitatively evaluated by integrating the revised universal soil loss equation (RUSLE) with a digital elevation model (DEM) and geographical information system (GIS) software. The standard RUSLE factors were modified to account for local climatic and topographic characteristics reflected in the DEM maps,and for the soil types and vegetation cover types. An interface was created between the Arcinfo software and RUSLE so that the level of soil erosion and its ecological risk in the WLSS area could be mapped immediately once the model factors were defined for the area. The results from an analysis using the Arcinfo-RUSLE interface showed that the risk value in 93 % of the expanding western part of the WLSS area was moderate or more severe and the soil erosion risk in this area was thus large compared with that in the rest of the area. This paper mainly aimed to increase the awareness of the soil erosion risk in urbanizing areas and suggest that the local governments should consider the probable ecological risk resulting from soil erosion when enlarging and developing tourism areas. 相似文献
15.
MENGXiangfeng WUDexing 《青岛海洋大学学报(英文版)》2002,1(2):119-124
Based on the analysis of Levitus data, the climatic states of the warm pool in the Indian Ocean (WPIO) and in the Pacific Ocean (WPPO) are studied. It is found that WPIO has a relatively smaller area, a shallower bottom and a slightly lower seawater temperature than those of WPPO. The horizontal area at different depths, volumes, central positions, and bottom depths of both WPIO and WPPO show quite apparent signals of seasonal variation. The maximum amplitude of WPIO surface area‘s seasonal variation is 58% larger over the annual mean value. WPIO‘s maximum volume variation amplitude is 66% larger over the annual mean value. The maximum variation amplitudes of the surface area and volume of WPPO are 20.9% and 20.6% larger over the annual mean value respectively. WPIO and WPPO show different temporal and spatial characteristics mainly due to the different wind fields and restriction of ocean basin geometry. For instance, seasonal northern displacement of WPIO is, to some extent, constrained by the basin of the Indian Ocean, while WPPO moves relatively freely in the longitudinal direction. The influence of WPIO and WPPO over the atmospheric motion must be quite different. 相似文献
16.
The International Symposium ‘Towards Sustainable Livelihoods and Ecosystems in Mountainous Regions’, held in Chiang Mai from 7-9 March 2006 (hereafter referred to as ‘Mountain Symposium’), brought together a wealth of experience from mountain research… 相似文献
17.
1 INTRODUCTION In marine waters, water temperature and nutrient Si control the temporal and spatial variation of the phytoplankton growth (Yang et al., 2006). The effect of nutrient Si and water temperature on the mecha- nism of phytoplankton growth has p… 相似文献
18.
1 IntroductionManymeteorologistsandoceanographerspaidmuchattentiontothestudyofthemechanismofENSOformanyyears,suchasBjerknes(1 966) ,Wyrtki(1 975) ,McCreary(1 983 ) ,Philander(1 984) ,ZhangandChao(1 993 )andMcCPhaden(1 998)havemadegreatdevelopmentinthestudyofENSO .Especiallyinthe 1 990’s,withtheincreasingofthedatainthedeepocean ,thesomeonearguedthattheENSOepisodehadcloserelation shipwiththeeasterntransportationoftheanomalousseasurfacetemperatureinthewestPacific(LiandMu 1 999;Huang 2… 相似文献
19.
WANG Weiwu 《山地科学学报》2007,4(3):237-247
In China, many scenic and tourism areas are suffering from the urbanization that results from physical development of tourism projects, leading to the removal of the vegetative cover, the creation of areas impermeable to water, in-stream modifications, and other problems. In this paper, the risk of soil erosion and its ecological risks in the West Lake Scenic Spots （WLSS） area were quantitatively evaluated by integrating the revised universal soil loss equation （RUSLE） with a digital elevation model （DEM） and geographical information system （GIS） software. The standard RUSLE factors were modified to account for local climatic and topographic characteristics reflected in the DEM maps, and for the soil types and vegetation cover types. An interface was created between the Areinfo software and RUSLE so that the level of soil erosion and its ecological risk in the WLSS area could be mapped immediately once the model factors were defined for the area. The results from an analysis using the Areinfo-RUSLE interface showed that the risk value in 93 % of the expanding western part of the WLSS area was moderate or more severe and the soil erosion risk in this area was thus large compared with that in the rest of the area. This paper mainly aimed to increase the awareness of the soil erosion risk in urbanizing areas and suggest that the local governments should consider the probable ecological risk resulting from soil erosion when enlarging and developing tourism areas. 相似文献