Abstract:

The position study on the effect of the intermediate cuttings intensity on Cunninghamia lanceolata stand growth was carried out on Zaoxia Forest Farm of Fengxin County,Jiangxi Province in June,1976.The tested stand was 10 years old.The study had been carried out for 20 years and ended in November,1996. The experimental results indicated that the average tree height and its periodic increment of the stand with the heavy,moderate or light intermediate cuttings increased by 3%～8% over those of the check,but the periodic increment difference is not significant,and the intermediate cuttings was unable to effectiviely promote the growth of the tree height. The average DBH and its periodic increment of the intermediate cuttings stand increased by 7%～19% and 6%～28% respectively as compared with those of the check and were higher significantly or extremely than those of the check. The intermediate cuttings effectively promoted the growth of the DBH. The total basal area and its periodic increment of the intermediate cuttings stand increased by 4%～6% and 1%～7% respectively as compared with those of the check,but there was no significant difference among the intermediate cutting intensity,the basal area of remaining trees of the intermediate cuttings stand was less than that of the check,and the intermediate cutting could not effectively increase the total basal area of the stand,basal area of the remaining trees and their increment. The individual volume and its periodic increment of the intermediate cuttings stand were significantly different or extremely significantly different in 5 years and in 8 years after the felling,which might effectively promote the individual increment of the stand. The unit-area total volume increment of the intermediate cutting stand increased by 2%～4% as compared with that of the check,the increase or decrease values of the remaining tree volume,living tree final-felling volume and their periodic increment were all within the allowable error scope as compared with those of the check,their difference was not significant,and the intermediate cutting could not effectively increase the volume increment and its total yield. As for the growth effect,it was suitable for carrying out the heavy intermediate cutting to fell about 40% of trees in a stand of C. lanceolata.

Key words: Cunninghamia lanceolata stand, intermediate cuttings intensity, growth effect