亚高山云冷杉混交林树木生长释放与干扰分析

Growth release and disturbance of conifer trees in subalpine spruce fir mixed forest\

对云南碧塔海亚高山云冷杉林内４个样地冠层树木的生长压制和释放的历史，用树木年轮分析方法进行了重建，然后根据生长释放频率推测林冠干扰强度（每１０年冠层树木的死亡百分率）。４个林分（１个中龄林，３个成过熟林）生长释放的平均百分率为４８％～９２％。中龄林内，平均生长释放频率为７１％／１０ａ，成过熟林则为７４％～９５％／１０ａ，在油麦吊云杉〔Ｐｉｃｅａｂｒａｃｈｙｔｙｌａｖａｒ．ｃｏｍｐｌａｎａｔａ（Ｍａｓｔ．）ＣｈｅｎｇｅｘＲｅｈｄ．〕占优势的林分和大果红杉（Ｌａｒｉｘｐｏｔａｎｉｎｉｖａｒ．ｍａｃｒｏｃａｒｐａＬａｗ）油麦吊云杉混交林分内，估测的林冠干扰强度分别为４８％／１０ａ和５９％／１０ａ。

Tree ring analysis was used to reconstruct the history of growth suppression and release of conifer trees in four stands within a subalpine spruce fir mixed forest in Bitahai Natural Reserve, northr west of Yunnan Province. And then, the canopy disturbance intensity (the percent of mortality of canopy trees per decade) were infered from the frequency of the growth release. For all stands (one was young growth, the others were old growth), the average values of growth release frequency were 7.1% per decade in young stand and 7.4% to 9.5% per decade in the old stands. The estimated disturbance intensities were 4.8% per decade in the stand dominated by Picea brachytyla var. complanata (Mast.) Cheng ex Rehd. and 5.9% per decade in Larix potaninii var. macrocarpa Law Picea brachytyla var. complanata (Mast.) Cheng ex Rehd. stand.