Study On Forest Healthy Management In Nature Larix Dahurica In Great Xing’an Mountain

This study investigated the stand structure of4typical stands types of nature larix dahurica in Tahe, Great Xing’an mountain.2011, Based on these data, disscussion about the aim, principal, targeted stands and management technology of forest healthy management had been made. Finally, we evaluated the effects of healthy management in two typical stands. Concluded that:(1)Stand structure in4typical stands of nature larix stands were determined in terms of tree species composition, spatial structure, diameter distribution, tree competition index and community diversity, results showing that (a) all of stand average diameter, height, stand volumn, conifers ratio and larix important value increased as the stands developed into climax, then declined as stands postmature. Stand density were highest in mid-sucession stage, and lowest in postmature.(b) In terms of spatial structure, there were no significant difference in uniform angle index between the four types of stands. Uniform angle index was0.519in youth forest of nature larix stand, which was aggregated distribution. Mingling index was lowest in birch forest, higher in mid-succession stage, then declined in climax and rebounce in postmature stand. As larix stands sucession to climax, diameter size increased, however, declined in postmature stage. Thus, larix play an critical role in the community sucession of larix stands in Great Xing’an Mountain.(c) As for diameter distribution, stands diameter classes increased as stand developed, and its morphology shifted from reversed"J" to unimodel distribution, then to bimodel distribution and finally back to unimodel.The q value dynamic shown the same pattern.(d) Stand competition index decreased as stand developed.(e) community diversity index were generaly lowest in early sucession stage, got higher hereafter, and declined in climax community, but got rebounce in postmature stage.(2)Based on the above analysis, method and principal of healthy management were proposed, and the specific management schems were worked out.(3)Incorporated with the healthy management methodology and aim, based on forest health condition, healthy management evaluation index were proposed, which had both precise and relative universality in indicate the effects of healthy manament.(4)According to our evaluation, both the two model healthy management methods (artifitial regeneration and forest thinning) could improve stand conditions in terms of species diversity, regeneration efficiency, stand productivity, thus, significantly increased stand sustainbility, anti-disturbance capability and sucession process, indicating that both method were well suited to the current forest condition in Tahe, and could be promoted in Great Xing’an mountain region.