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Search Results: 1 - 10 of 8388 matches for " KANG Shichang "
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Elemental composition of aerosols collected in the glacier area on Nyainqêntanglha Range, Tibetan Plateau, during summer monsoon season
ChaoLiu Li,ShiChang Kang,ZhiYuan Cong
Chinese Science Bulletin , 2007, DOI: 10.1007/s11434-007-0445-0
Abstract: In order to investigate the elemental composition in atmospheric aerosols and its sources in the glacier area over the Tibetan Plateau (TP), seven totally suspended particle samples were collected continuously at the col of the Zhadang glacier (30°28′N, 90°39′E, 5800 m a.s.l.), Nyainqêntanglha Range, southern TP, from June to October 2006. Twenty-seven elements (Li, Be, B, Na, Mg, Al, K, Ca, Sc, Ti, V, Fe, Mn, Zn, Ga, As, Rb, Sr, Y, Cd, Cs, Ba, Tl, Pb, Bi, Th, U) were analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The result indicates that the concentrations of most elements (especially crustal elements) are lower than values at the Nam Co Station during the same period of 2005, and also much lower than other sites in the TP such as Wudaoliang and Waliguan. This suggests that elemental compositions of aerosols in the Zhadang glacier area may represent the background levels of the middle/upper troposphere over the TP. Crustal enrichment factors (EFs) reveal that several elements (e.g. B, Zn, As, Cd, Pb and Bi) may have anthropogenic sources. The southern TP is mainly influenced by the summer Indian monsoon during the sampling period. Backward air mass trajectory analysis suggests that air masses in the region may originate from South Asia. Therefore, anthropogenic pollutants from South Asia may be transported by the summer Indian monsoon to the region which clearly affects the atmospheric environment in the southern TP during the summer monsoon season.
Seasonal features of aerosol particles recorded in snow from Mt. Qomolangma (Everest) and their environmental implications
Seasonal features of aerosol particles recorded in snow from Mt. Qomolangma (Everest) and their environmental implications

CONG Zhiyuan,KANG Shichang,QIN Dahe,
CONG Zhiyuan
,KANG Shichang,QIN Dahe

环境科学学报(英文版) , 2009,
Abstract: To assess the seasonality of aerosol deposition and anthropogenic effects on central Himalayas, a 1.85-m deep snow pit was dug on the northern slope of Mr. Qomolangma (Everest). Based on the morphology and energy dispersive X-ray (EDX) signal, totally 1500 particles were classed into 7 groups: soot; aluminosilicates; fly ash; calcium sulfates; Ca/Mg carbonates; metal oxides; and biological particles and carbon fragments. The size distribution and number fractions of different particle groups exhibited distinct seasonal variations between non-monsoon and monsoon periods, which are clearly related to the differences in air mass pathways. Specifically, the relative abundance of soot in non-monsoon period (25%) was much higher than that in monsoon period (14%), indicating Mr. Qomolangma region received more anthropogenic influence in non-monsoon than monsoon period.
The Matching Uniqueness of A Graphs  [PDF]
Shichang Shen
Applied Mathematics (AM) , 2015, DOI: 10.4236/am.2015.68109
Abstract: In the paper, We discussed the matching uniqueness of graphs with degree sequence \"\" . The necessary and sufficient conditions for\"\" and its complement are matching unique are given.
Temporal and Spatial Aspects of Snow Distribution in the Nam Co Basin on the Tibetan Plateau from MODIS Data
Jan Kropacek,Chen Feng,Markus Alle,Shichang Kang,Volker Hochschild
Remote Sensing , 2010, DOI: 10.3390/rs2122700
Abstract: Large areas of the Tibetan plateau are only covered by a sparse network of ground snow sampling stations, while the snow cover is highly heterogeneously distributed due to wind, topography etc. Nevertheless, the snow accumulation and spatial patterns play an important role in the hydrological cycle. It releases moisture during the dry spring period before the onset of the monsoon season. Widely used MODIS snow cover products have been available globally since 2002. The understanding of the temporal and spatial distribution of snow cover in a given region calls for a comprehensive data representation method. In this paper a method to visualize both spatial and temporal aspects of snow cover distribution from MODIS 8-day composite data is presented. It is based on RGB display of the snow cover data which is grouped according to season. The RGB syntheses of snow cover distribution (RSD) were generated for the Nam Co Basin in the central part of the Tibetan Plateau during the years of 2002–2009. An alternating pattern of monsoon and autumn snow cover was identified in the western part of the basin which corresponds to the biennial character of the variations of the Indian monsoon. Monsoon snow cover was found in RSD images for the years 2002, 2004 and 2008 whereas in years 2003 and 2009 the autumn snow cover is dominant. The eastern part of the basin does not follow this general pattern since it is affected by the so called “lake effect”, which is a snow fall induced by the passing of dry and cold westerlies over the lake surface during the winter months. The years 2002, 2006 and 2007 were identified as years with a particularly strong lake effect from the RSD images. Areas with permanent snow cover and areas that were snow free were both found to be relatively stable. Comparison of the lake effect at Nam Co with nearby Siling Co, where the lake effect is smaller or absent, suggests that the presence of an effective barrier on the opposite side of the lake is a prerequisite for the occurrence of the strong lake effect.
Mercury speciation and spatial distribution in surface waters of the Yarlung Zangbo River, Tibet
Wei Zheng,ShiChang Kang,XinBin Feng,QiangGong Zhang,ChaoLiu Li
Chinese Science Bulletin , 2010, DOI: 10.1007/s11434-010-4001-y
Abstract: The Yarlung Zangbo River is the highest river in the world. It flows from west to east through the southern part of Tibet. The mercury (Hg) speciation and distribution in surface waters and soils near the bank of the Yarlung Zangbo River and its two tributaries, the Lhasa and Niyang Rivers, were investigated in June 2007. Simultaneously, major water quality parameters were also measured at the same stations. Total Hg (THg) and total methylmercury (TMeHg) concentrations in surface waters of the Yarlung Zangbo River ranged from 1.46 to 4.99 ng/L and from 0.06 to 0.29 ng/L, respectively, representing the background levels in river systems of the Tibetan Plateau. Particulate Hg (PHg) accounted for 69% of the THg, and the two Hg species had a significant relationship (r=0.990, P<0.01). Approximately 61% of the spatial distribution of THg was controlled by the concentrations of total suspended particles (TSP). Reactive Hg (RHg) concentrations ranged from 0.10 to 0.36 ng/L, and this fraction may play a weak role in terms of the transport and fate of Hg in surface waters. Dissolved methylmercury (DMeHg) constituted 71% of the TMeHg and was significantly correlated with TMeHg (r=0.746, P<0.01). The spatial distribution of TMeHg is not strongly affected by environmental factors such as THg, RHg, temperature, pH, dissolved organic carbon (DOC), and TSP. In addition, the inflow of both the Lhasa and Niyang Rivers probably influences the concentrations of THg in surface waters of the mainstream, but such an effect is not obvious for TMeHg.
Elemental composition in surface snow from the ultra-high elevation area of Mt. Qomolangma (Everest)
QiangGong Zhang,ShiChang Kang,ZhiYuan Cong,ShuGui Hou,YongQin Liu
Chinese Science Bulletin , 2008, DOI: 10.1007/s11434-007-0446-z
Abstract: A total of 14 surface snow (0–10 cm) samples were collected along the climbing route (6500–8844 m a.s.l.) on the northern slope of Mt. Qomolangma in May, 2005. Analysis of elemental concentrations in these samples showed that there are no clear trends for element variations with elevation due to redistribution of surface snow by strong winds during spring. In addition, local crustal aerosol inputs also have an influence on elemental composition of surface snow. Comparison between elemental concentration datasets of 2005 and 1997 indicated that data from 2005 were of higher quality. Elemental concentrations (especially for heavy metals) at Mt. Qomolangma are comparable with polar sites, and far lower than large cities. This indicates that anthropogenic activities and heavy metal pollution have little effect on the Mt. Qomolangma atmospheric environment, which can be representative of the background atmospheric environment.
A method for estimating the contribution of evaporative vapor from Nam Co to local atmospheric vapor based on stable isotopes of water bodies
YanWei Xu,ShiChang Kang,YuLan Zhang,YongJun Zhang
Chinese Science Bulletin , 2011, DOI: 10.1007/s11434-011-4467-2
Abstract: During the summer monsoon season, the moisture of precipitation events in southern and central regions of the Tibetan Plateau is mainly moisture from the Indian Ocean transported by the Indian monsoon and terrestrial vapor derived from the surface of the Tibetan Plateau. However, the respective contributions of these two types of moisture are not clear. From June to September, the excess deuterium values of precipitation and river water in the Nam Co basin are higher than those for the southern Tibetan Plateau. This reflects the mixing of evaporation from Nam Co and local atmospheric vapor. On the basis of theory for estimating the contribution of evaporative vapor from surface water bodies to atmospheric vapor and relative stable isotopes in water bodies (precipitation, river water, atmospheric moisture and lake water), this study preliminarily estimates that the average contribution of evaporation from the Lake Nam Co to local atmospheric vapor has varied from 28.4% to 31.1% during the summer monsoon season in recent years.
Response of Zhadang Glacier runoff in Nam Co Basin, Tibet, to changes in air temperature and precipitation form
ShiQiao Zhou,ShiChang Kang,TanGuang Gao,GuoShuai Zhang
Chinese Science Bulletin , 2010, DOI: 10.1007/s11434-010-3290-5
Abstract: This paper describes 2007/2008 inter-annual changes in runoff from the Zhadang Glacier located on the northern slope of Nyainqêntanglha Range, Tibet, and analyzes their causes. Precipitation increased by 17.9% in summer months of 2008 compared with the same period in 2007, drainage basin runoff decreased by 33.3%, and glacial meltwater decreased by 53.8%. Change in positive accumulated air temperature explained approximately half of the inter-annual difference in glacial meltwater using a degree-day model. This suggests that the glacier is extremely sensitive to changes in air temperature. Energy balance analysis showed that change in glacier surface albedo, considered to be caused by difference in precipitation form, resulted in the large inter-annual difference in glacial meltwater. It was shown statistically that precipitation form in the summer months of 2007 was mainly rainfall which comprised 71.5% of total precipitation, while during the same period in 2008 rainfall accounted for 30.7%, with the majority of precipitation falling as snow. Precipitation form should be considered an independent factor when analyzing glacier sensitivity to climate change or forecasting the runoff from certain glaciers.
Review of the studies on climate change since the last inter-glacial period on the Tibetan Plateau
青藏高原不同时段气候变化的研究综述

Chaoliu Li,Shichang Kang,
李潮流
,康世昌

地理学报(英文版) , 2006,
Abstract: As the “Third Pole” of the world, the Tibetan Plateau has important effects on climate of its surrounding areas and even the whole world. Many results have been achieved on climate change since the last inter-glacial period in recent decades from ice core, tree-ring and lake sediment records over the Tibetan Plateau. In this paper, we review these achievements, especially those in the special periods. During the last inter-glacial period, temperature went down rapidly and went up slowly. The temperature record of the last glacial period is consistent with Greenland ice core records, also having own features over the Tibetan Plateau. Younger Dryas event agrees with the records from Europe and Greenland. Generally speaking, it is warm in the Holocene, and temperature has been rising gradually in the last 2000 years and gone up rapidly in recent decades. Climate changes on different time scales on the Tibetan Plateau occurred earlier and the change amplitude is larger than those in other parts of China. Foundation: Hundred Talent Program of CAS; National Natural Science Foundation of China, No.40401054; No.40121101; Knowledge Innovation Project of CAS, No.KZCX3-SW-339; President Foundation of CAS Author: Li Chaoliu (1978-), Ph.D., specialized in paleo-climate environmental change.
Review of the studies on climate change since the last inter-glacial period on the Tibetan Plateau
青藏高原不同时段气候变化的研究综述

LI Chaoliu,KANG Shichang,
李潮流
,康世昌

地理学报 , 2006,
Abstract: As the "third pole" of the world, the Tibetan Plateau has important effects on climate in its surrounding areas and the whole world. Achievements have been gained on climate change since the last inter-glacial period in recent decades from ice core, tree-ring, and lake sediment records over the Tibetan Plateau. In this paper, we reviewed these achievements, especially those in the special periods. During the last inter-glacial period, temperature dropped rapidly and rose slowly. The temperature record of the last glacial period is consistent with Greenland ice core records, also having its own trait over the Tibetan Plateau. Younger Dryas event agrees with the records from Europe and Greenland. It is warm generally in Holocene, and temperature has been rising in the last 2000 years and gone up rapidly in the last decades. Climate changes at different scales on the Tibetan Plateau occur earlier and the extent is greater than that in other parts of China.
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