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比较研究了南亚热带几种植被下丘陵赤红壤结构特征．结果表明，丘陵赤红壤的结构随着植被的演退而退化．表现在表土砂化，即砂粒含量相对增加，粘粒含量相对减少；土壤结构稳定性下降，主要体现在较大粒径水稳性团聚体减少；土壤孔隙性变差，主要体现在容重增加和较大孔径的孔隙减少．自然赤红壤容重增加、较大孔隙减少更为明显；耕型赤红壤结构稳定性下降，表土砂化更为突出．研究结果揭示，由植被演退引起的土壤有机质减少，是丘陵赤红壤结构退化的主要内在因素．
Comparatively studied the structural characteristics of latosolic red soil in the hilly areas of southern subtropics. The results showed that the structure of hilly red soil degenerated with the evolution of vegetation. The results show that in the topsoil sandification, that is, the sand content is relatively increased, the clay content is relatively decreased, the soil structure stability is decreased, which is mainly reflected by the decrease of the larger particle size water-stable aggregates and the poor soil porosity. Pores with larger pores decrease. Natural red soil bulk density increased, the larger the pore reduction is more obvious; tillable red soil structure stability decreased, surface sandification is more prominent. The results revealed that the reduction of soil organic matter caused by the vegetation regression is the main internal factor of the degradation of hilly red soil.