不同起源兴安落叶松林结构特征的比较

Comparative Study on Characteristics of Stand Structures in Larix gmelinii Forests of Different Origin

比较了兴安落叶松天然林(3种林型)与人工林生产力、林木竞争分化、水平格局、林分更新、林下地被物等方面的特征。结果表明:①人工林生产力明显高于天然林。在密度和林龄相近情况下,人工林蓄积量、生物量和生产力较天然林分别高65.0%、35.8%、48.8%。②天然林直径分布反J型,人工林单峰型。天然林和人工林1～5级木的比例由大到小排序:4(32.4%)>3(30.5%)>2(14.7%)>1(12.9%)>5(9.5%);3(32.2%)>2(30.5%)>4(25.4%)>1(10.2%)>5(1.7%)。③天然林聚集系数与林分密度呈正相关,其随机分布和聚集分布比例为52.9%、47.1%。人工林为随机分布。④天然林林分更新较好,人工林无林分更新。人工林藓类盖度、草本盖度、植被种类等明显低于天然林平均水平。

Comparative study was conducted between natural Larix gmelinii forests （three forest types） and plantations in the productivity, tree differentiation, distribution pattern, stand regeneration, vegetation change and other characteristics. The results indicated： First, plantation productivity is significantly higher than that of the natural forest. With similar density and stand age, plantation volume, biomass and productivity are higher 65.0%, 35.8% and 48.8% than those of natural forests, respectively. Second, natural forests diameter is inverted-J-shaped distribution, while plantation is single peak. Ratio of Class 1-5 stem in descending order are 4（32.4% ）〉3（30.5% ）〉2（14.7% ）〉1（12.9% ）〉5（9.5% ） for natural forest and 3 （ 32.2% ） 〉2 （30.5 % ） 〉4 （25.4%） 〉 1 （ 10.2% ） 〉5 （ 1.7 % ） for plantation, respectively. Third, for natural forest, clustering coefficient has positive correlation with stand density, and the random distribution and clustered distribution are 52.9% and 47.1%, respectively. Plantation is with random distribution. Fourth, the stand regeneration for natural forest was better, while there is no regeneration for plantation. Moss cover, herbaceous cover and vegetation types etc. in nature forest are significantly higher than the average levels in plantation.