| Summary: | Soil systems continuously gain and lose matter and energy even in areas where climate is too harsh to support the higher plants such as in higher elevations and in permafrost environments. !e purpose of this paper was to elucidate soil formation at 4 700 m asl in the Kunlun Mountains of the Qinghai (Tibet) Plateau, China. We collected twenty-six samples from three pedons developed on carbonaterich slate and quartzitic-sandstone materials. !e samples were analyzed for routine physical, chemical and mineralogical properties. Our results indicate that soil-forming processes are barely taking place in the study site as shown by pH > 7.0 re"ecting limited decarbonation, biological activity (< 1.0% total C and < 0.05% total N), podzolization (<1 g Fep+Alp kg-1 soil) and lessivage. The relative amounts of mica and kaolinite show no apparent change with depth suggesting minimal transformation and translocation of phyllosilicates. !e most noticeable mineral transformation resulted in micaceous "flakes" and feldspathic "fragments" possibly due to thermal stress. Calcite is also observed coating the slate fragments. The soils are classified as Cryosols in the World Reference Base system and Gelisols in the Soil Taxonomy with ochric epipedon as the only diagnostic horizon indicating recent development of soils due to cold and arid environment. !e results of this study show that soil-forming processes in harsh environments are manifested in the mechanical breakdown of minerals such as mica and feldspars. O sistema solo ganha e perde continuamente massa e energia mesmo em áreas em que o clima é demasiado severo para o desenvolvimento das plantas tais como áreas de elevada altitude e ambientes "permafrost". O objectivo deste trabalho foi esclarecer a formação do solo a uma altitude de 4700 m nas Montanhas de Kunlun (Tibete) no Planalto de Qinghai (China). Recolheram-se 26 amostras de três pedons desenvolvidos em ardósias carbonatadas e materiais areníticos quartzozos. As amostras foram submetidas a uma análise de ...
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