干旱区生态环境知识资源中心

Three cold desert soil sites were first found in the southern Mount Harding, Grove Mountains, East Antarctica. The soils are characteristics of the widespread occurrence of surface desert pavement, abundant water-soluble salts, strongly stained upper portion of soil profile, slightly acid and negligible organic matter content. A 1:5 soil-water extracts analysis indicates that the dominant cations are Mg2+ and Na+, followed by Ca2+ and K+, and the main anion is SO42-, then 4 Cl- and NO3-. The accumulation of water-soluble salts indicates ion transportation in the frigid and arid Antarctica environment. The distribution of the salts is related to the maximum content of moisture and clay mineral. Clay fraction migration occurs in the soils, which is different from that of other cold desert soils. The upper horizons of some profiles are generally stained, namely rubification, primarily because of the weathering of iron-bearing minerals. The reddish hues of cold desert soils have been attributed to relatively high concentrations of dithionite-extractable Fe (Fe-d). The weathering features of soils suggest that the soil age of this area is 0.5-3.5 Ma. No remnants of glaciations were found on the soil sites of Mount Harding, which suggests that the Antarctic glaciations have not reached the soil sites since at least 0.5 Ma, even during the Last Glacial Maximum.