它们主要来源于母质，其次来自成土过程，降尘输入量极有限。

These clay minerals mainly come from parent material, a few from pedogenic processes, and dust input is minute.

youdao

它们主要来源于母质，其次来自成土过程，降尘输入量极有限。

These clay minerals mainly come from parent material, a few from pedogenic processes, and dust input is minute.

youdao