红松次生混交林中针叶树与阔叶树的结构差异

摘要

红松混交林是中国东北地区最重要的植被类型,在缓解全球气候变化、保证木质产品供给和维护生物多样性中扮演重要角色.该研究以吉林东大坡自然保护区第52林班的水曲柳红松混交林和第54林班的核桃楸-红松混交林为例,采用林分结构参数一元分布(UDSSP)、二元分布(BDSSP)和非线性模型(NLM)分析了它们的针叶树和阔叶树的结构特征,以探讨混交林中针、阔树种组之间的关系,为低效次生林的改造提供参考.结果显示:(1)多数针叶树同时处于高混交和优势状态,仅有极少数个体处于中庸或劣势;多数阔叶树亦处于高混交状态,且不同优势的树木总数几乎相等.(2)大部分树木都同时处于高度混交和随机分布状态,少量针叶树略偏向规则分布.(3)大部分针叶树同时处于随机分布和优势状态,且不同优势的阔叶树皆倾向随机分布,而处于规则或聚集分布的数量很少.(4)针叶树和阔叶树的径阶分布均能够较好地通过指数函数或幂函数描述.这些特征充分展示了空间格局和径阶分布在不同群落类型之间差异很小,但在不同树种组之间存在明显差异.%Korean pine mixed forest is one of the most important vegetation in northeast China.It plays an important role in alleviating global climate change,guaranteeing the wooden product supply and maintaining biological diversity.Four plots located at the 52thand 54th compartments,Dongdapo nature preserve,Jiaohe,Jilin province,were analyzed by using the univariate distribution (UDSSP) and bivariate distribution (BDSSP) of stand structural parameters and nonlinear model (NLM),with the purpose to clear the relationship between coniferous and hardwood species,which may contribute to the reconstruction of lowproduct secondary forests.These stands stood for Fraxinus mandschurica Rupr.and Pinus koraiensis Sieb et Zucc.mixed forest and Juglans mandshurica Maxim.and P.koraiensis mixed forest,respectively.The results showed that:(1) Most conifers were in a state of high mixture and dominance,and only few belonged to the middle or inferior plants;the majority of hardwoods were also intensely surrounded by other species and the ones with different dominance showed an equal number;(2) Many individuals were intensely mixed and randomly distributed at the same time,the slightly difference was conifers biased towards regularity when compared with hardwoods;(3) Most conifers were randomly distributed and had advantage on sizes,while few medium or inferior trees had the same pattern.Hardwoods with different dominance were randomly distributed and only few were regular or clump;(4) Their diameter classes were well expressed by power function or exponential functions.These features revealed that spatial patterns and diameter distributions were closely similar within different types of forest stand and differed from conifers to hardwood species groups.