Soil properties of ancient Cinnamomum camphora at different sites in the lakeside scenic area of Hangzhou

Key words: 
• soil science /
• Cinnamomum camphora /
• soil properties /
• different natural stand conditions /
• lakeside scenic area of Hangzhou

Abstract: Soil physical and chemical properties as well as nutrient contents under ancient Cinnamomum camphora crown projections were studied at the lakeside scenic area of Hangzhou，where a high water table and strong human disturbance were found，using a correlation analysis. Results showed that soil pH was partially alkaline varying from 6.57 to 7.58；soil bulk density was loose varying from 0.75 to 1.28 gcm－3；organic matter content varied from 16.1 to 78.8 gkg－1；and overall the soil nutrient levels were above average. A strong positive correlation（P＜0.05） among soil total N，total P，total K，hydrolysable N，and available P were found. Additionally，a negative correlation was found between soil exchangeable Ca and exchangeable Mg （P＜0.05），but there was no correlation among different microelements. Soil properties in the green space of the Three Pools Mirroring the Moon Scenic Area were superior to the green space，lawn，and tree ponds at Round Lake which was more beneficial to the growth of ancient C. camphora trees. In tree ponds，soil properties with ceramic and bark mulch were superior to turf grass or seeded grass as mulch；however，the human activities that readily disturbed ancient C. camphora growing in tree ponds meant that the coefficient of variation with ceramic and bark mulch was higher than with grass mulch. The higher pH would be harmful to the growth of Cinnamomum camphora. Therefore，the balance of soil pH，aeration，water and fertilizer conservation will be improved by covering the tree pool with organic mulch such as bark and wood chips，avoiding laying sod and seeding within the projection region of the crown，and reducing the alkaline substances such as soil cement，lime and bricks mixed in the soil after the transformation in the scenic spots.［Ch，5 fig. 1 tab. 18 ref.］