黄土高原古土壤形态特征的差异及成因探讨

灵台剖面第四纪晚期古土壤－这里指Ｓ８及其上古土壤；第四纪中早期古土壤－这里指离石黄土Ｓ９及其下古土壤和午城黄土中所有古土壤；第三纪古土壤－指么三纪红粘土，在形态特征上有明显区别。这种区别是由于古成土过程中水分运行方式的不同造成的。根据形态特征和古成土过程水作用方式的差异，把上述３个时代的古土壤依次淋溶型古土壤、滞圹地下水升降型古土壤。不同时代古土壤成土过程水作用方式的这种差异，是由降水量、尘降速率

Different Morphological Features of the Paleosols in the Loess Plateau, Northwest China and Their Formations

The Lingtai section includes both the Quaternary loess paleosol sequence and the Tertiary red clay. The investigations revealed that the morphological features of the paleosols of the section formed in late Quaternary (S 0-S 8), middle and early Quaternary (S 9-S 41 ) and late Tertiary (the Tertiary red clay) were different to large extent. It was caused by the different water migrating patterns during the paleo pedogenetic processes. According to the variations of the morphological features and the paleo pedogenesis, the paleosols in the different periods mentioned above were classified as the leaching type paleosols, the stagnating type paleosols and the ground water fluctuating type paleosols, respectively. The variations of the paleosols' morphological features, which are common in the Loess Plateau, were caused by the changes of environmental factors, mainly precipitation and dust accumulation rate. A correct understanding of it will help us further interpret the palaeo climates and palaeo environments of the Loess Plateau, northwest China since the late Cenozoic.