Holocene paleosols and paleoclimate for the arid upper Minjiang River valley in the eastern Tibetan Plateau

The pedogenic features of Holocene paleosols and their paleoclimatic significance in the arid upper Minjiang River valley of the eastern Tibetan Plateau, southwest China, were investigated using elemental geochemistry, particle size distribution, and magnetic susceptibility indices in combination with the min-max normalization and paleoclimate reconstruction methods. Paleosols developed in a semi-humid environment and were classified as Inceptisols and Entisols. Pedogenic intensity of these paleosols was higher in the Middle Holocene and lower in the Early and Late Holocene. Mean annual precipitation (MAP) and mean annual temperature (MAT) inferred from the paleosols formed in the Middle Holocene are similar to 700 mm and similar to 13 degrees C, respectively. Modern climate is cooler and drier than that of the Middle Holocene and resembles that of the Early Holocene and the period after the last glacial maximum. Climatic changes in the study region were sensitive to the Asian monsoon evolution, which was controlled by orbital forcing. Relative warmer and wetter conditions perhaps triggered the ancient cultural immigration and prosperity at similar to 6000 cal. yr BP in the arid valley region.