Analysis of Structure Characteristics of Main Tree Species in Spruce-Fir Overcutting Forest
In order to propose new design ideas of recovering mixed stand which mainly composed by Pinus koraiensis,some issues about stand structure were discussed and analyzed,such as diameter,spatial pattern,stand volume growth,regeneration and plant diversity,based on three types of overcutting spruce-fir forest on Changbai Mountains.The most difference among the forests was the ratio of conifer trees to broad-leaved trees,with steppedrates of 9∶ 1,8∶2 and 7∶ 3.The results showed that:P.koraiensis forest became cutting object because of unreasonable and non-operating cutting in the past.The amount of P.koraiensis trees greatly changed among different diameter intervals,and loss happened when diameter greater than 18 cm,which led to the decline of parent tree,seed and provenance,contrary to positive evolution.The spatial pattern of mixed stand was not exactly the same as that of the main tree species,and showed difference among different trees in the same stand.The three forests with different needle/broadleaf ratios followed a random,aggregation and uniform distribution.P.koraiensis assumed aggregation distribution.So the following should be done to recover mixed stand which mainly composed of P.koraiensis.1.Taking P.koraiensis and precious broadleaf species as the goal,adopting the target tree cultivation method,removing the trees affecting the renewal and growth of target trees,taking spruce fir and broad-leaved tree as accompanying species,weakening the dominance of spruce and fir,and eventually restored the stand gradually to the P.koraiensis and broad-leaved mixed stand; 2.For the stand with conifer tree and broadleaved tree mixed in the ratio of 8∶2 and 7∶3,changing aggregation distribution into uniform distribution through repair planting,intermediate cutting and combined with natural regeneration; 3.Adopting artificial supplementary interventions to help the natural regeneration of P.koraiensis,such as repair planting,litter cleaning and so on.
NETL
NSTL
万方数据
维普
