Assessment of the dominant climatic factor affecting pedogenic development in eolian sequences during the Holocene in arid central Asia

Eolian sediments are widely distributed and are one of the most important geological archives of past climatic changes. For example, the degree of pedogenic development of loess is widely used as an indicator of precipitation amount. However, in the case of arid lands, characterized by drought conditions and where potential evaporation is much higher than precipitation, it is unclear whether precipitation is the sole factor dominating pedogenic development, or whether temperature is also an important factor affecting for pedogenic development. In this study, we compared variations in pedogenic development of sequences of Holocene eolian sediments in arid basins and humid high mountains in Northwest China to assess the role of precipitation and temperature in soil development. The results indicate that the variation trend of pedogenic development was similar in both arid basins and high mountains, with weak development in the early Holocene and gradually increasing development into the late Holocene. In addition, combining both temperature and moisture records reveals that the weakest soil development was in the early Holocene when the climate was warm and dry and the strongest soil development was in the late Holocene when the climate was warm and humid. Overall, our results reveal that precipitation was the dominant climatic factor controlling changes in pedogenic development in the study area.