Resources Evaluation
ZHANG Chi, GAO Yun-hua, CHEN Xu-fei, ZHOU Bo, LI Jin, REN Zong-ling, DAI Jun
The study aimed to observe physical and chemical properties of lateritic red soil under different land uses in South China, such as pH, clay contents, bulk density, porosity, organic carbon, total contents of nitrogen, phosphorus, potassium and their available contents. Relationships between these variables, soil quality under different land uses and their main key factors were evaluated by principal component analysis (PCA). Results showed that: the highest bulk density in soil and the lowest clay content and porosity were observed in the newly cultivated dryland; while the lower contents of soil organic C, total N, P, K, available N and P were found as well (P<0.05). The orchard soils have the lowest bulk density in these four kinds of land uses, and higher contents of total N, available N, P and K were showed in our study (P<0.05). Compared to shrub land, the eucalyptus forest soil has higher total and available K contents but lower clay and available P contents, respectively (P<0.05). PCA results showed that significant differences in soil physical and chemical qualities were observed in newly cultivated dry land, orchard land, eucalyptus forest and shrub land (P<0.05), especially the lowest quality were found in newly cultivated dry land. Lower contents of organic C, nitrogen, available N resulted in the lower soil quality of the newly cultivated dry land. In the meantime, lower contents of available P and K limited the improvement of soil quality in eucalyptus forest and shrub land. PCA can not only distinguish physical and chemical properties of lateritic red soil under different land uses, but also can detect their main factors.