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Through comparison of snow-pit NO3– profiles from central East Antarctica and the northern Qinghai-Tibetan Plateau (QTP), we conclude that NO3– peaks in the uppermost surface snow layers in central East Antarctica are not related to an atmospheric signal and that they need to be accounted for by post-depositional effects. Such effects, however, are not found in the snow-pit NO3– profiles from the northern QTP. NO3– can be deposited as a gas (HNO3–) or as a neutral salt, particularly by reaction with ammonia to form NH4NO3, or fixed by sea salt or terrestrial dust (Mulvaney and others, 1998). Thus, a difference in speciation between NO3– in snow layers in East Antarctica and at the northern QTP is suggested as the reason for the different post-depositional processes of NO3– in the two areas.

In a controversial venture, officials plan to halt open grazing, eradicate rodents, restore "degraded" grasslands, improve wetlands, and plant many trees and shrubs.

According to geological research, North China was in a dry-cold stage from 25,000 to 10,000 BP, which can be correlated temporally with Oxygen isotope stage 2 of the deep-sea record. Since ca. 10,000 BP, North China and the Qinghai-Tibetan Plateau entered the Holocene warm stage. Though there have been some shifts from cool to warm and from dry to humid in this stage, and several cold events can be recognized in many places, the general tendency has been toward warming. Along with the environmental amelioration at the end of the Pleistocene, human occupation in these regions emerged in more vigorous condition than ever before. The scale of migration and diffusion reached a maximum in the Optimum of the middle Holocene. Archaeologically, the most obvious sign of the Pleistocene–Holocene transition was the development of microliths.

Available climatic observation data are very limited in Qinghai-Tibetan Plateau (QTP) because of its severe physical environment. Great efforts have been made to assimilate remote sensing data and in situ observation data to produce qualified datasets. This study has verified the applicability of a ground meteorological forcing dataset named CMFD in a typical site (TGL) and a typical region (XKL) in QTP by the simulation of water-heat processes with land surface model (LSM). Results show that Noah LSM simulation with CMFD-derived forcing data can accurately present the water-heat conditions of individual site as well as typical region on QTP with an NSE of 0.818 for TGL site and mean annual ground temperature discrepancy less than 1 degree compared with observation data of 8 boreholes in the total 10 boreholes in XKL. It is proved that CMFD dataset can be used as reliable data source for simulation applications on QTP.

Local residents of the Lhasa River Region (LRR) on the Qinghai-Tibetan Plateau in western China have noticed that the surrounding mountains have appeared conspicuously green since the 1980s. To verify these claims, we investigated trends of grassland activities in the LRR from 1982 to 2013 by using remotely sensed Normalised Difference Vegetation Index (NDVI) data, as a proxy for photosynthetic activity. Due to the limitation of available remote sensing data, we used long-term data with low resolution, GIMMS3 g NDVI, to explore the temporal changes between 1982 and 2012; we used moderate resolution data, MODIS NDVI, to investigate the spatial variations of trends between 2001 and 2013. In addition, we examined the relationship between grassland change and climate change. The results revealed a significant upward trend in the annual mean NDVI of the LRR from 1982 to 2012, corroborating the observations of the local people. The increasing trend was more pronounced during the period of 1982–1999 than during the period of 2000–2012. The seasonal NDVI also exhibited a significant upward trend in spring and summer from 1982 to 1999. From the higher resolution MODIS NDVI data analysis, during 2001–2013, the lower regression slope values were mainly distributed in the river valley (the area of lower elevation), whereas the higher values pixels were located in the northern LRR (the area of higher elevation). In addition, the annual NDVI correlated significantly with temperature and precipitation during the study period. Temperature is a more significant factor influencing grassland change than precipitation in spring and autumn. However, the precipitation with the time lag effect is more significantly correlated with NDVI during the growing season (from May to October). The results of this project will help to monitor regional vegetation changes, understand the impact of climate change, and better manage the economically, environmentally and culturally significant grasslands of the LRR.

1 (Seed), respectively. The content of arctigenin in seed was significantly higher than in other organs of S. medusa . Compared to distribution of arctigenin in different organs of S. medusa , arctigenin mainly exists in reproductive organs and in vegetative organs with trace of S. medusa.

In this paper we measured the long-term thickness change of the Dongkemadi Glacier(DG) on Tanggula Mountain, Qinghai-Tibetan Plateau, using the Shuttle Radar Topography Mission (SRTM) C-band data(2000) and a digital elevation model(DEM) generated from topographic map(1969). First we check the accuracy of SRTM DEM by comparison at 16 random independent points in surrounding non-glacier area below 5500m a.s.l., then we focus on an analysis of the glacier's surface thickness change features and a validation of the results using GPS survey data (2007) and DEM(1969) in Xiao Dongkemadi Glacier(XDG). The result shows XDG decreased by an average of 6.15m, or 0.20 m a-1 between 1969 and 2000. We estimate the error of annual thickness change rate to be on the order of 5% compared to the result of field measurement while Da Dongkemadi Glacier(DDG) decreased by an average of 20.74m or 0.67m a-1(1969–2000).

Recently, plant-derived methane (CH 4 ) emission has been questioned because limited evidence of the chemical mechanism has been identified to account for the process. We conducted an experiment with four treatments (i.e. winter-grazed, natural alpine meadow; naturally restored alpine meadow eight years after cultivation; oat pasture and bare soil without roots) during the growing seasons of 2007 and 2008 to examine the question of CH 4 emission by plant communities in the alpine meadow. Each treatment consumed CH 4 in closed, opaque chambers in the field, but two types of alpine meadow vegetation reduced CH 4 consumption compared with bare soil, whereas oat pasture increased consumption. This result could imply that meadow vegetation produces CH 4 . However, measurements of soil temperature and water content showed significant differences between vegetated and bare soil and appeared to explain differences in CH 4 production between treatments. Our study strongly suggests that the apparent CH 4 production by vegetation, when compared with bare soil in some previous studies, might represent differences in soil temperature and water-filled pore space and not the true vegetation sources of CH 4 .

The glacier is important factor in climatological and hydrological investigations, especially in the western China. Glacier changes are among the clearest signals of on-going warming trends existing in nature. In view of environmental changes, combined with the high thermal sensitivity of earth's mountain glaciers, especially in Qinghai-Tibetan Plateau, is of growing interest. SAR systems have an important ability to observe the earth's surface, independent of cloud conditions. Particularly, the SAR interferometry provides a useful tool for monitoring the velocity of glacier movement. For accurate measurement of glacier movement with InSAR data, the suitable method of retrieving velocity of glacier motion need be considered for the different type of glaciers in case of the difference of the characteristics of surface and movement velocity. In this paper, we use the SAR interferometry to derive the movement of several types of glaciers and analyze the characteristics of different glaciers type, such as continental glacier, sub-continental glacier and maritime glacier, and demonstrate the method and results for the glacier motion in the Qinghai-Tibetan plateau

The Tibetan Plateau is the center-piece of the broad India-Eurasia collision zone, and a natural laboratory to study large-scale continental deformation. We analyze Tibet campaign data from 1993 to 2002 and some continuous Global Positioning System (GPS) stations around Tibet using GAMIT/GLOBK software. The data analysis involves two major procedures. The first procedure uses the GAMIT software to estimate parameters such as station position and orbital trajectory on a daily basis from the union of two data sets: (a) the campaign stations, and (b) long-running continuous GPS stations around Tibet. In the second procedure, we combine the daily solutions with global GPS sub-networks (IGS1, IGS2, IGS3), which are provided by Scripps Institute of Oceanography (SIO), using the GLOBK software in a “regional stabilization” approach in order to estimate the positions and velocities. Then we discuss present-day crustal movement of Qinghai-Tibetan Plateau, and determine the strain rate. The conclusion is that the Himalayan block is mainly under compressing strain, and the maximum compressing rate is -98.5 ± 4.2 nstrain/yr and with the extension rate of 26.7 ± 2.8 nstrain/yr in the direction of N127.1 ± 0.7°E; the middle part of the Tibet block is mainly under compressing strain, and the maximum compressing rate is -20.3 ± 1.2 nstrain/yr in the direction of N39.0 ± 2.0°E with the extension rate of 10.8 ± 1.6 nstrain/yr in the direction of N129 ± 2.0°E. Both principal compressing strain rate and extension rate trails off from the Himalayan block to the middle part of the Tibet block. Besides, GPS result shows that Tibet Plateau uplifts with 3–5 mm per year

[1] The ambient concentrations of carbonyl compounds were measured in Waliguan (WLG) Observatory at the east edge of Qinghai-Tibetan in August–September and December, 2005. The average concentrations of formaldehyde, acetaldehyde, acetone, and 2-butenal were 4.16 ± 1.89, 4.25 ± 3.32, 2.02 ± 0.86, and 1.93 ± 1.58 ppbv (n = 42), respectively, in August–September and 1.48 ± 0.42, 3.91 ± 0.81, 1.88 ± 0.69, and 0.69 ± 0.16 ppbv (n = 12), respectively, in December. Biomass used as fuel for cooking by local residents was considered as the dominant source for 2-butenal. Photooxidation of VOC (especially biogenic emission of isoprene) was one source for formaldehyde and methyl vinyl ketone in August–September. Animal excrement was probably an additional source for formaldehyde and acetone. Back trajectory analysis indicated that long-distance transportation from polluted air might be one important source for formaldehyde, acetone, and acetaldehyde in WLG.

Climatic change over Qinghai-Tibetan Plateau is controlled by alternation of the plateau summer and winter monsoon circulation, which is triggered by thermodynamic and kinetic effects of the high plateau morphology. Loess-paleosol sequences in northeast Qinghai-Tibetan Plateau are investigated to reconstruct variations of the plateau monsoon changes during the Last Glacial-Interglacial cycle. On the basis of grain-size data from two loess-paleosol sequences that can be used as a proxy indicator of the plateau monsoon climate changes, we find a short climatic reversal during transition from the most warm-humid period of the Last Interglacial period (corresponding with marine oxygen isotope stage 5e (MIS 5e)) to the subsequent relatively cold-dry period (corresponding with MIS 5d). In contrast to the Younger Dryas event, this climatic event shifted toward more humid conditions reflects an episode of reduced strength of the plateau winter monsoon and increased influence of the plateau summer monsoon. The age of this paleoclimatic event is estimated at 111-113 ka BP. This climatic reversal expresses instability of the plateau monsoon system during transformation from a wet-warm to a dry-cold climate. It may have been caused by the high topography that amplified climatic change in the Northern Hemisphere during the transition from MIS 5e to MIS 5d. (c) 2006 Elsevier Ltd and INQUA. All rights reserved. Climatic change over Qinghai-Tibetan Plateau is controlled by alternation of the plateau summer and winter monsoon circulation, which is triggered by thermodynamic and kinetic effects of the high plateau morphology. Loess-paleosol sequences in northeast Qinghai-Tibetan Plateau are investigated to reconstruct variations of the plateau monsoon changes during the Last Glacial-Interglacial cycle. On the basis of grain-size data from two loess-paleosol sequences that can be used as a proxy indicator of the plateau monsoon climate changes, we find a short climatic reversal during transition from the most warm-humid period of the Last Interglacial period (corresponding with marine oxygen isotope stage 5e (MIS 5e)) to the subsequent relatively cold-dry period (corresponding with MIS 5d). In contrast to the Younger Dryas event, this climatic event shifted toward more humid conditions reflects an episode of reduced strength of the plateau winter monsoon and increased influence of the plateau summer monsoon. The age of this paleoclimatic event is estimated at 111-113 ka BP. This climatic reversal expresses instability of the plateau monsoon system during transformation from a wet-warm to a dry-cold climate. It may have been caused by the high topography that amplified climatic change in the Northern Hemisphere during the transition from MIS 5e to MIS 5d. (c) 2006 Elsevier Ltd and INQUA. All rights reserved.

Background Chronic mountain sickness (CMS), originally characterized by excess hemoglobin (Hb), is currently diagnosed using score-based diagnostic criteria combined with excessive erythrocytosis and clinical symptoms. However, the current criteria have limited applicability. We applied these criteria to 1,029 Chinese Han males migrated to and have been stayed at the Qinghai-Tibet plateau (3,700–5,000 m) for 2–96 months to investigate the prevalence of CMS and its correlations with Hb concentration, altitude, and the length of residence. Methods Subjects were screened for CMS using the latest approved diagnostic criteria combined with excessive erythrocytosis and clinical symptoms. Hb concentrations were measured, and a cut-off point was determined with k-means clustering. Predisposing factors were evaluated with binary logistic analysis and curve fitting analysis. Results (1) The prevalence of CMS at the Qinghai-Tibetan plateau was 17.8% (183/1029 subjects, with CMS score ≥ 6, and Hb ≥ 210 g/L), which is higher than that previously reported. (2) While individuals were identified into two Hb clusters with a cut-off point of 200 g/L, in the low-Hb cluster (Hb 4500 m.

Aim The study aimed to identify areas of endemism for aphids in the QinghaiTibetan Plateau and the Himalayas (QTPH), and to test congruence between patterns of endemism and patterns of overall species richness identified in a previous study. Location The QTPH. Methods A distribution data base of 326 endemic aphids in the QTPH was compiled. The study area was divided into a grid of 2�· 2� operative geographical units. Parsimony analysis of endemicity (PAE) was used to identify areas of endemism, and the diversity patterns of endemic species were then mapped using GIS. Results We identified 326 endemic species belonging to 138 genera within Adelgidae and 14 subfamilies of Aphididae. Five areas of endemism were found using PAE analysis: the eastern Himalayas, the western Himalayas, north-western Yunnan, southern Tibet and the eastern QTPH. Maps of patterns of endemism identified four major centres for endemic aphids, namely the western Himalayas, the eastern Himalayas (or Sikkim-Assam Himalayas), north-western Hengduan Mountains and the mountains of southern Gansu Province, and three minor centres, southern Tibet, south-eastern Tibet and the eastern Qinghai Province in the north-eastern QTPH. Main conclusions Our study identifies major centres of aphid endemism. Furthermore, there is a noticeable congruence between patterns of endemism and patterns of species richness. The patterns of endemism were most likely influenced by the recent uplift of the QTPH.

This work makes the quantitative constrain on tectonizations of the Gangdese block, south Qinghai-Tibetan Plateau. Apatite fission track (AFT) dating analyses of 15 samples collected across the Gangdese block show that the Gangdese block went through two periods of tectonizations, during ∼37.2-18.5 Ma and 18.5-8.0 Ma in the south Gangdese block, and during ∼47.6-5.3 Ma and 5.3-0 Ma in the middle Gangdese block. Different upliftings did not take place in the first period and rapid uplifting occurred in the late period. Meantime, there are some differences between the south and middle Gangdese block. Their uplifting rate is 180 m/Ma and 70 m/Ma respectively. The rapid uplifting time in the middle Gangdese block lagged behind the time in the south Gangdese block. It is Chala-Jiacuo-Riduo fault zone that is similar to the Yarlung Zangbo fault zone in control of the tectonization.

Considerable attention has been paid to, and significant achievements have been made in the meteorology of the Qinghai-Tibetan plateau (hereafter called the plateau for brevity) in recent years. One should mention the recent establishment of an observational network in that region. Through these new observational data many new and important findings were obtained, some of which are summarized in a book “Meteorology Over Qinghai-Tibetan Plateau” [19]. These new research results point towards the dynamical and thermal importance of the plateau in shaping atmospheric circulation systems. The plateau's dynamic effects have long been noticed [3, 2, 5]. Its thermal effects were also pointed out in earlier literature [20, 7] and were studied relatively intensively in recent years. It is the purpose of this paper to give a discussion of the thermal influence of the plateau, starting with estimates of the seasonal variation of the intensity of the heat source over the plateau, followed by a discussion on the influence of the heat source on the atmospheric circulation. The role of convective activity in maintaining the large-scale summer circulation over the plateau is described next. Finally, some comparisons between the effects of the plateau and of the tropical oceans on summer atmospheric circulations are given.

In the epicenter of the Lushan M S7.0 earthquake there are several imbricate active reverse faults lying from northwest to southeast, namely the Gengda-Longdong, Yanjing-Wulong, Shuangshi-Dachuan and Dayi faults. Emergency field investigations have indicated that no apparent earthquake surface rupture zones were located along these active faults or their adjacent areas. Only brittle compressive ruptures in the cement-covered pavements can be seen in Shuangshi, Taiping, Longxing and Longmen Townships, and these ruptures show that a local crustal shortening occurred in the region during the earthquake. Combining spatial distribution of the relocated aftershocks and focal mechanism solutions, it is inferred that the Lushan earthquake is classified as a typical blind reverse-fault earthquake, and it is advised that the relevant departments should pay great attention to other historically un-ruptured segments along the Longmenshan thrust belt and throughout its adjacent areas.

Diagnosing the degradation degree of grassland ecosystem is the basis for ecological restoration. However, there is no literature documenting how to quantify the grassland degradation degree by using visible indicators. In this study, an integrated degradation index was developed to assess the grassland condition on the basis of applicability and certainty analysis through a cases study from degraded alpine grassland on Qinghai-Tibetan Plateau of China.

Compiled by w. s. F. Kidd; from field data of Geotraverse participants compiled by J. F. Dewey as field sheets during Geotraverse; interpretation of LANDSAT orbital images, supplemented in places by Shuttle large-format camera and Spacelab metric camera orbital images; Geological map of the Qinghai-Xizang Plateau. 1:1.5 m. (1980); Geological map of Qinghai, 1:1 m. (1985); Carte géologique du sud du Tibet, 1:1/2 m. CNRS (1983). See Kidd, Chang, Coward, Dewey, Gansser, Molnar, Shackleton, Sun (1988) - Geological mapping (this volume) for more details. For cross-sections, see Coward et. al. (this volume). Base map from Defence Mapping Agency Operational Navigation Charts G-8 (ed. 3) and H-10 (ed. 7), modified with detail from orbital imagery and 1:100,000 topographic maps. Lambert conformal conic projection. Geogtraverse Participants: Chang Chengfa*, Chen Nansheng, M. P. Coward, Deng Wanming, J. F. Dewey, F. R. S.ᶧ, A. Gansser, N. B. W. Harris, Jin Chengwei, W. S. F. Kidd, M. R. Leeder, Li Huan, Lin Jinlu, Liu Chengjie, Mei Houjun, P. Molnar, Pan Yun, Pan Yusheng, J. A. Pearce, R. M. Shackleton, F. R. S.*, A. B. Smith, Sun YiYin, D. R. Watts, Xu Juntao, Xu Rongjua, Yin Jixiangᶧ, Zhang Yuquan *Expedition leader, ᶧdeputy leader