说明6种恢复林地土壤有机碳含量均出现表聚现象，从表层到深层都呈现递减趋

Description 6 kinds of restored woodland soil organic carbon accumulation in surface phenomena all appear, from the surface to the deep have shown a decreasing trend, and has a certain regularity. This is mainly due to the accumulation and decomposition of vegetation and surface litter roots played a strong role in the accumulation of organic carbon in the soil surface.

It is shown that the organic carbon content of the soil in the six kinds of restored forest land has the phenomenon of surface aggregation, and the decreasing trend is shown from the surface to the deep, and has certain regularity. This is mainly due to the accumulation and decomposition of vegetation root system and surface falling matter, which plays a strong role in the accumulation of organic carbon on the soil surface.

The results showed that the soil organic carbon content of six kinds of restoration forest land appeared the phenomenon of surface accumulation, from the surface layer to the deep layer showed a decreasing trend, and had a certain regularity. This is mainly due to the accumulation and decomposition of plant roots and surface litter, which play a strong role in the accumulation of soil surface organic carbon.<br>