江西省主要森林类型下土壤的物理性质

THE PHYSICAL PROPERTIES OF SOIL UNDER THE MAJOR TYPES OF FOREST IN JIANGXI

本项研究表明，常绿阔叶林下土壤由于枯枝落叶层构型完整，并在地表形成了一层独特的根盘层，从而保持了土壤完整的发生学层次和良好的物理性状。与之相比较，杉阔混交林和杉木纯林下的土壤由于地表枯枝落叶层和根盘层的破坏，侵蚀作用使土壤的发生层产生逆向发育，土壤各种物理性状明显恶化，且以后者为最快，这些土壤物理性状的恶化主要表现在：（１）土壤质地突变或粗骨化；（２）土壤结构性变差；３）土壤孔隙状况恶化，土壤的持水能力下降；（４）土壤的渗透性下降。

The study showed that the litter layers under ever-green broad-leaved forest developedwell,and a specific root-mating layer formed on the mineral soil surface,which protected the soil genesis horizons from erosion and led to good soil pnysical properties.But in contrast,seri-ous regressive development of soil genesis horizon and deterioration of soil physical property in-cluding,(1)abruption or skeletonization of soil texture,(2)deterioration of soil structure,(3)degeneration of soil porosity and moisture holding ability,(4)soil penetrability worsening wereobserved under the mixed forest of ever-green broad-leaved and Chinese Fir and putr Chi-nese Fir forest due to the distroyment of the litter layer and the root-mating layer,especiallyunder the latter.