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This article investigates the soil properties in two soil profiles from the terraces of the Nam Co Lake in Tibet, China. Profile 1, with a slope aspect to east, is 37 m, and profile 2, to southwest, is 32 m above the lake level. Twelve and nine layers were identified in profile 1 and profile 2, respectively, based on the color, texture, structure, moisture content, presence of carbonate, and root density. Grain sizes and measurements of water content, total organic carbon, total inorganic carbon, total carbon, pH value and electrical conductivity were all analyzed for each sample. The results show that soil is poorly developed because of sparse vegetation coverage and weak chemical weathering in the cold and arid area. The results also indicate that the soil properties are different between the two profiles and suggest that soil is better developed in profile 1 than in profile 2. These differences are ascribed to the dissimilarity of landform, vegetation and timing. Profile 1 faces to east as compared with profile 2 facing to southwest and gets less insolation and therefore less evaporation. Thus, vegetation grows better in profile 1 than in profile 2. Radiocarbon dating and OSL dating show that profile 1 underwent a longer soil forming process than profile 2, which is helpful for the soil development in profile 1. [ABSTRACT FROM AUTHOR]

This overview discusses old and new results as to the controversy on the past glacier extension in High Asia, which has been debated for 35 years now. This paper makes an attempt to come closer to a solution. H.v. Wissmann’s interpretation (1959) of a small-scale glaciation contrasts with M. Kuhle’s reconstruction (1974) of a large-scale glaciation with a 2.4 million km2 extended Qinghai-Xizang (Tibetan) inland glaciation and a Himalaya-Karakorum icestream network. Both opinions find support but also contradiction in the International and Chinese literature (Academia Sinica). The solution of this question is of supraregional importance because of the subtropical position of the concerned areas. In case of large albedo-intensive ice surfaces, a global cooling would be the energetical consequence and, furthermore, a breakdown of the summer monsoon. The current and interglacial heat-low above the very effective heating panel of the Qinghai-Xizang (Tibetan) Plateau exceeding 4000 m, which gives rise to this monsoon circulation, would be replaced by the cold-high of an inland ice. In addition, the plate-tectonically created Pleistocene history of the uplift of High Asia — should the occasion arise up to beyond the snowline (ELA) — would attain a paleoclimatically great, perhaps global importance. In case of a heavy superimposed ice load, the question would come up as to the glacio-isostatic interruption of this primary uplift. The production of the loesses sedimentated in NE-China and their very probable glacial genesis as well as an eustatic lowering of the sea-level by 5 to 7 m in the maximum case of glaciation are immediately tied up with the question of glaciation we want to discuss. Not the least, the problems of biotopes of the sanctuary-centres of flora and fauna, i.e., interglacial re-settlement, are also dependent on it. On the basis of this Quaternary-geomorphological-glaciological connection, future contributions are requested on the past glaciation, the current and glacial permafrost table and periglacial development, the history of uplift, and the development of Ice Age lakes and loess, but also on the development of vegetation and fauna in High Asia. [ABSTRACT FROM AUTHOR]

The source area of the Yellow River is located in the northeastern Tibetan Plateau, and is a high-elevation region with the annual mean temperature of −3.9°C. The ice-wedge casts discovered in this region are recognized as two types. One was found in sandy gravel beds of the second terrace of the Yellow River. This ice-wedge cast is characterized by higher ratio of breadth/depth, and are 1–1.4 m wide and about 1 m deep. The bottom border of the ice-wedge cast is round arc in section. Another discovered in the pedestal of the second terrace has lower ratio of width/depth, and is 0.3–1.0 m wide and 1–2 m deep. Its bottom border is sharp. Based on the TL dating, the former was formed at the middle Holocene (5.69 ± 0.43 ka BP and 5.43 ± 0.41 ka BP), that is, the Megathermal, and the latter was formed at the late Last Glacial Maximum (13.49 ± 1.43 ka BP). Additionally, the thawing-freezing folders discovered in the late Late Pleistocene proluvium are 39.83 ± 3.84 ka BP in age. The study on the ice-wedge casts showed that the air temperature was lowered by up to 6–7°C in the source area of the Yellow River when the ice-wedge casts and thawing-freezing folds developed. [ABSTRACT FROM AUTHOR]