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Abstract: This paper introduce a passive solar house in Tibet, which was divided into two parts by trombe wall, by measuring the temperature of two different parts, the result showed that the temperature in heat preserve room and bath room appeared different changes but had the similar trend with outside temperature. [Copyright &y& Elsevier]

• Premise of the study: Little is known about the effect of environmental conditions on seed dormancy break at the community level or how it could be affected by climate change. This study tested the effects of storage conditions on germination of 489 species from high-elevation natural grasslands on the Tibet Plateau. • Methods: We stored seeds in dry cold, dry warm, and wet cold environments to test the effect of these conditions on germination. Germination responses were classified with the use of cluster analysis. The effect of phylogeny on germination response to storage conditions was determined. • Key results: Compared with results of wet cold conditions, storing seeds at dry warm or dry cold conditions decreased the mean community germination percentage by 17.93% and 16.07%, respectively. Storing seeds at dry warm vs. dry cold conditions decreased the community mean germination percentage by 4.61%. The germination response to moisture conditions during storage showed significant phylogenetic patterns, whereas the germination response to storage temperature did not. On the basis of the germinability of seeds of the same species stored under different conditions, germination may increase, decrease, or stay the same. • Conclusions: Within the high-elevation Tibetan grassland community, the different responses in dormancy breaking and germination behavior to the same storage conditions may have implications for understanding how this community might respond to climate change, in particular, some species may increase in the community, whereas others may decrease or remain the same. However, the potential for such change can be detected only by studying the responses of many species. [ABSTRACT FROM AUTHOR]

Thermal waters from the Yangbajing geothermal field, Tibet, contain high concentrations of B, As, and F, up to 119, 5.7 and 19.6 mg/L, respectively. In this paper, the distribution of B, As, and F in the aquatic environment at Yangbajing was surveyed. The results show that most river water samples collected downstream of the Zangbo River have comparatively higher concentrations of B, As, and F (up to 3.82, 0.27 and 1.85 mg/L, respectively), indicating that the wastewater discharge of the geothermal power plant at Yangbajing has resulted in B, As, and F contamination in the river. Although the concentrations of B, As, and F of the Zangbo river waters decline downstream of the wastewater discharge site due to dilution effect and sorption onto bottom sediments, the sample from the conjunction of the Zangbo River and the Yangbajing River has higher contents of B, As, and F as compared with their predicted values obtained using our regression analysis models. The differences between actual and calculated contents of B, As, and F can be attributed to the contribution from upstream of the Yangbajing River. Water quality deterioration of the river has induced health problems among dwellers living in and downstream of Yangbajing. Effective measures, such as decontamination of wastewater and reinjection into the geothermal field, should be taken to protect the environment at Yangbajing. [ABSTRACT FROM AUTHOR]

The climate change in Tibet has induced complex water resource and geo-environmental changes. Tibet is located in a unique geographical zone with the characteristics of middle-low latitude, high altitude and very low average air temperature, and the climate there has been changed both in time and in space under the effect of global warming. Except for two regions without data, the changes of both air temperature and rainfall in the last 35 years in Tibet exhibit evident zonational patterns. In general, air temperature increases higher from east to west, whereas rainfall changes from decrease to increase from south to north. Except for some areas in southern Tibet, the general increase of rainfall accelerated the rate of water cycle, and caused an increase in the gross amount of water resources in Tibet. Moreover, under the impact of climate change, the frequency of occurrence of landslide and debris flow has slightly increased in the high mountain–canyon regions of eastern Tibet. Also, the debris flow due to ice lake outburst has evidently increased in the plateau mountain–lake basin regions of southern Tibet. By contrast, desertification in the western plateau–lake basin regions of northern Tibet has been intensified. [ABSTRACT FROM AUTHOR]

To evaluate the effects of preventing and controlling brick-tea type fluorosis, we carried out a 3-year field observation and assayed the total daily fluoride intake, urinary and serum fluoride level, and dental fluorosis prevalence and index in a boarding school in Dangxiong, Tibet, in students aged 8–15. We replaced the traditional brick tea with low-fluoride brick tea (LFBT). Reduction in the traditional brick-tea consumption decreased the total daily fluoride intake among the children, which still remained within the level of chronic intoxication but at a safe level. The study suggests that the LFBT is effective in the prevention and control of endemics of brick tea type fluorosis, although further improvement of the LFBT is required. [Copyright &y& Elsevier]

The pattern and timing of deformation in southeast Tibet resulting from the early stages of the India-Asia collision are crucial factors to understand the growth of the Tibetan Plateau, but they remain poorly constrained. Detailed field mapping, structural analysis, and geochronological and thermochronological data along a 120 km section of the Ludian-Zhonghejiang fold-and-thrust belt bounding the Jianchuan basin in western Yunnan, China, document the early Cenozoic tectonic evolution of the conjunction between the Lanping-Simao and South China blocks. The study area is cut by two major southwest-dipping brittle faults, named the Ludian-Zhonghejiang fault and the Tongdian fault from east to west. Numerous kinematic indicators and the juxtaposition of Triassic metasedimentary rocks on top of Paleocene strata indicate thrusting along the Ludian-Zhonghejiang fault. Similarly, structural analysis shows that the Tongdian fault is a reverse fault. Between these structures, fault-bounded Permian-Triassic and Paleocene rocks are strongly deformed by nearly vertical and upright southwestvergent folds with axes that trend nearly parallel to the traces of the main faults. Zircon and apatite (U-Th)/He and apatite fissiontrack data from a Triassic pluton with zircon U-Pb ages of 237-225 Ma in the hanging wall of the Ludian-Zhonghejiang fault, assisted by inverse modeling, reveal two episodes of accelerated cooling during 125-110 Ma and 50-39 Ma. The Cretaceous cooling event was probably related to crustal thickening during the collision between the Lhasa and Qiangtang terranes. The accelerated exhumation during 50-39 Ma is interpreted to record the life span of the fold-and-thrust belt. This timing is corroborated by the intrusive relationship of Eocene magmas of ca. 36-35 Ma zircon U-Pb age into the fold-and-thrust belt. Early Cenozoic activity of the deformation system controlled deposition of alluvial-fan and braided-river sediments in the Jianchuan basin, as evidenced by eastward and northeastward paleoflows and terrestrial clasts derived from the hanging wall of the Ludian-Zhonghejiang thrust. Since 39 Ma, decreasing cooling rates likely reflect cessation of activity on the fold-and-thrust belt. Early Cenozoic compressive deformation on the western margin of the South China block together with geological records of contraction in central, northern, and eastern Tibet document Eocene upper-crustal shortening located in the Himalaya, Qiangtang terrane, and northern plateau margins together with contractional basin development in the intervening Lhasa, Songpan-Garze, and Kunlun terranes, coeval with or shortly after the onset of the India-Asia collision. This suggests that moderate crustal shortening affected a large part of Tibet in a spaced way, contrary to models of homogeneous crustal thickening soon after the collision, and prior to the main crustal thickening, propagating progressively from south to north. This complex deformation pattern illustrates the complexity of Asian crustal rheology, which contrasts with assumptions in existing geodynamic models. [ABSTRACT FROM AUTHOR]