A Study on the Influence of Site Management Measures on the Growth of Four-year-old Chinese Fir Plantation of Second-generation

Aimed at studying the influence of various patterns of site management on the productivity of Chinese fir (Cunninghamia lanceolata) plantation for generations, the second generation C. lanceolata plantation was established with 5 kinds of site preparation patterns on the cleared area of first generation C. lanceolata. The results showed that: (1) The pattern IV (Double slash) had the most benefits to the growth of 4 year old C. lanceolata of second generation, and had the most effects on reducing soil bulk specific gravity and raising soil pH value. This is the best site management pattern. (2) The pattern II (Whole tree harvest) was the worst. (3) The pattern I (No slash) had positive effect on the growth of C. lanceolata in 1 2 years after planting, but it had negative effect on soil fertility maintenance. (4) The pattern V (Stem and bark harvest + burning) was better than the pattern III (Stem + bark harvest), but the difference is not significant. (5) It is estimated that it will take about 90 months for the harvest residual to be decomposed to the 5% of the weight remains.