土壤的风化程度既受风化壳类型的影响,又有很多独特的方面。因此,对于风化壳类型及其地理分布的研究并不能代替土壤风化带的研究。自然土壤的形成过程,是风化淋溶过程(即地质过程)和生物累积过程共同作用的结果。无论风化淋溶过程或生物累积过程都受生物气候条件的制约,因而随着生物气候带的演替,便都显示出各自的地带性。张效年、李庆逵先生在《华南土壤的粘土矿物组成》一文中阐明了华南土壤生成过程的风化带,并且指出:“热带红壤区及亚热带红壤 The degree of weathering of soils is affected both by the type of weathering crust and by a number of unique aspects. Therefore, the research on weathering crust type and its geographical distribution can not replace the study of soil weathering zone. The formation of natural soil is the result of a combination of weathering and leaching processes (ie, geological processes) and bioaccumulation processes. Both the weathering leaching process and the bioaccumulation process are constrained by the bioclimatic conditions, and thus their zonality is shown with the succession of bioclimatic zones. Zhang Xiaonian and Li Qinglian clarified the weathered zone of the soil-forming process in South China in the article “Clay Mineral Composition of Soils in South China,” and pointed out that "the red soil region in the tropics and the subtropical red soil