The temporal-spacial change of soil moisture and nutrients on terrace in the mountainous region of southern Ningxia

The paper primarily analyzes the change of soil moisture in different sections of level terrace and the change of chemical properties on terrace constructed in different years. The result shows that on level terrace, the soil moisture at 0~100cm layer tends to be decreased from inner section to outer section, and the change is more apparent when the breadth of terrace is increased. As for soil nutrients, there is a depleting period in the preliminary period after the terrace is constructed, and they tend to be increased as the time passes, especially in the soil layers near to the land surface. The change of nutrients is extraordinarily apparent in 0~60 cm soil layer, but is relatively stable in the lower soil layer. 