Comparative Analysis on Soil Physi-Chemicai Properties and the Tree Growth in Taiwania flousiana Plantations and Successive Rotation Plantations of Cunninghamia lanceolata
Soil physi-chemical properties and the tree growth were compared in successive rotation plantations of Cunninghamia lanceolata (CR Chinese Fir) in tree different ages(8-year-old, ll-year-old and 14-year-old), and Taiwania flousiana plantations with the same age pattern which were afforested in previous slash of Chinese Fir. The results showed that soil balk densities were 0.893~1.112, 0.797-1.256 and 0.598-1.211 g·cm-3 respectively in 8,11,14-year-old Taiwania flousiana plantations soils (0 ~ 100 cm), which were lower 0.9%-6.9% than those in CR Chinese Fir plantations. Total soil porosity in the three ages of Taiwania flousiana plantations was respectively 45.69%-65.33% ,46.45%-68.74% and 39.82%-68.26% ,and all higher 6.6%-8.7% than that in the CB Chinese Fir plantations. The soil ventilation degree was respectively 49.57%-59.71%, 44.55%-66.68% and 42.38%-66.16% ,and also higher 14. 2 %-24. 4% than that in the CR Chinese Fir plantations. The soil saturation moisture capacity was respectively 3.43%-11.43% ,4.15%-19.73% and 2.28%-12.23%, and higher 12.4%-14.9% than that in the CR Chinese Fir plantations; The saturated water contents were 46.89%-66.50%, 40.90%-68.09% and 42.36%-98.15% respectively,and higher 12.4%-14.9% than that in the CR Chinese Fir plantations, pH values of forest soil (0-40 cm layer) were 4.30-5.10,4.40-4.80 and 4.13-4.55 respectively in 8,11,14-years-old of Taiwania flousiana plantations, which were lower 1.3%-6.3% than that in the CR Chinese Fir plantations,and the organic matter contents were 46. 03-71.45,34. 96-68. 67 and 25. 59-79. 38 g-kg-1,and lower that in CR Chinese Fir plantations in the 8-year-old,however higher 23. 4%-77. 1% than that in the 11,14-years-old. Total nitrogen and hydrolysis nitrogen contents were 1.78-3.55,1.97-3. 04,2.01-3. 12 g·kg -1 and 146. 9-355. 3,185.0-370. 5,136. 6-365. 9 mg·kg-1 ,and slightly lower than that in 8-year-old is and higher 20. 1% -35. 6% in the 11,14-years-old. Available P contents were 0.5-2.7,0.6-1.5 and 0.6-2.8 mg·kg-1 respectively,and higher than that 11.1% -54.5% in the CR Chinese Fir plantations. Available K contents were 15. 4-137. 5,34. 5-115.5 and 18. 7-89. 1 mg·kg-1 ,and lower 23.6%-47. 6% than that in the CR Chinese Fir plantations. In the 8,11,14 years-old of Taiwania floasiana plantations,the average diameter was 10. 70 ,12. 67 and 14. 13 cm respectively,and higher 12. 4%-36. 7% than that in the CR Chinese Fir plantations. The average tree height were 8.63,11.47 and 13.33 m respectively,and higher 11.7% -30.2% than that in the CR Chinese Fir plantations. Tree stands volumes were 93. 308,153. 418 and 203. 824 m3·hm-2 respectively,higher 37. 7%-117. 5% than that in the CR Chinese Fir plantations.
continuous planting Cunninghamia lance1olataTaiwania flousiana introduction experimentssoil physichemical propertiestree growthNandan County of Guangxi