| The Holocene loess-soil sequence on the Chinese Loess Plateau constitutes an excellent record of evolution of soil formation, monsoonal climate, eolian dust accumulation and influence of arable farming of over 10000 years. The Linfen Basin, one of the prehistoric culture centers in China, lies in the southeastern Loess Plateau. Three high-resolution soil profiles were selected in the Taosi area, middle of the Lifen Basin. DPG profile lies in the front of the palaeo-alluvial-pluvial fans of Ta'ershan hill, and TSC and LGK profiles on the 4th terrace of Fenhe River.Stratigraphic subdivisions were made by examining their color, texture and structure in the field. Samples were taken every 2 cm continuously down the profiles. A Munsell color chart was used to describe the color of sediment for air-dried samples. The profiles were studied using grain-size analysis, measurement of magnetic susceptibility, Fe, Al, Rb, Sr, Ba, Cu, Ni, CaCO3 and TOC (total organic carbon). The Stratigraphic boundaries were then checked with a variety of physical-chemical analytical results. The results provide new insights into the pedogenic environmental evolution and impact of human activities on soil development in this environmental sensitive zone.The main conclusions are following:(1) Influenced by climate, topography, human activities, and other factors, the pedogenic environment and pedogenic process were changeful in Taosi area in the Holocene.In the early Holocene (11500-8500 a B.P.), the sediment is much similar to the Malan Loess indicating that the climate was dominated by the northwest monsoon and dust accumulation was intensive. Pedogenic process was very weak.Before Late Taosi Culture(8500~4050 a B.P.), the sediment are characterized by their high percentage of clay, Fe2O3, Al2O3 , Cu, Ni, TOC and low percentage of CaCO3 , Sr and high magnetic susceptibility indicating climate was dominated by the southeast monsoon and dust accumulation was slow. Bio-pedogenic process was intensive and palaeosol developed. The soil in the front of the palaeo-alluvial-pluvial fans was short of moisture owing to different topographic condition, and thus,pedogenic intensity was lower compared with the profiles on the terrace.During Late Taosi Culture(4050~3850 a B.P.), rainfall was very abundant. Surface erosion took place on the palaeo-alluvial-pluvial fans , and deposition in the front of the fans and above the terrace. A rainwash bed was identified in DPG and LGK profile respectively, in which the sediment consists mainly of re-deposited loess mixed with a small quantity of sand-size grains. But no record of rainwash was in TSC profile which was inside the habitation region of Taosi site.From the end of Late Taosi Culture to the finish of the Holocene Megathermal (3850-3100 a B.P.), the bio-pedogenic process was increased in DPG and LGK sites, and pedogenic process ceased in TSC due to building.Over the last 3100years, as climate has become dry and dust-fall was intensive in Linfen Basin, the recent loess(Lo) has been deposited and covered the mid-Holocene soil(So). The pedogenic process was reduced in all of the three profiles.(2) Arable farming has been traced back to 8000 a B.P at latest in Linfen Basin, but cultivation had not affected the natural soil development until Late Taosi Culture. During Late Taosi Culture, cultivation changed the landform to some extent and promoted rainwash deposition in the front of the fans, and the soil moisture were increased, and thus, bio-pedogenic process increased till 3100 a B.P. In the habitation region, building terminated the soil formation, therefore human impact on the pedogenesis environment has masked the climatic fact in such spot. More and more potter shards, charcoal and sand were found in the recent loess (L0) and the present topsoil(TS) indicating that human impact on pedogenic process was intensive. Modern entironment deterioration and soil erosion have been caused by climate aridity and over cultivation by population pressure.(3) There are two important surface erosi...
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