冷杉腐朽病研究:Ⅲ.冷杉林木腐朽程度的探讨

Studies of Fir Rot Disease. Ⅲ. Rot Degrees of Fir Forest Trees

冷杉林木腐朽程度是冷杉林分质量变化的重要标志。研究表明,西部高山林区冷杉林木腐朽是严重的,腐朽木的腐朽高度占树高的11.8～32.6％,腐朽材积平均为3.8～20.4％(Ⅱ阶段后期腐朽)。林木腐朽状况以林木年龄为转移,过熟林木腐朽高度为1.8～10.3m,超过中龄林木(0.5～1.8m)的3～6倍。林木径级与腐朽程度(腐朽高度、腐朽材积)成正相关。腐朽高度与出林率为负相关。研究结果,伐根腐朽直径(X)与腐朽高度((?)_1)、腐朽材积((?)_2)、出材率((?)_2)建立回归方程:根据林(原)木的伐根腐朽直径,即可判别其出材等级范围。冷杉林分腐朽状况是个体被害林木的总和,而林木腐朽程度反映了冷杉腐朽病的严重性。可以认为,冷杉林分腐朽率是数量增长的概念,而林木内部腐朽程度则是质量变化的标志。基于此,本文着重从冷杉林木年龄、径级与腐朽程度进行了研究、探讨冷杉腐朽病危害的实质。

The rotten degree of fir trees is an important sign of quality of Abies forest. Investigation shows that the rotten degree of fir trees in alpine regions in westrn Sichuan is serious. The rotten height is 11. 8-32. 6% of total,the rotten volume is 3. 8-20. 4% in average. The diameter class of trees has positive corre-lation with the rotten degree, and while negative correlation with the rate of timber producing. The regression equation of rotten diameter of stump(X)with the rotten height (Y_1) ,the rotten volume (Y_2)and the rate of timber producing (Y_3)According to rotten diameter of stump (or olg base) ,it could be determine the range of timber producing.