【作者】 臧润国；

【导师】 徐化成； 吴榜华；

【作者基本信息】 北京林业大学 ， 生态学， 1995， 博士

【摘要】 本文选择位于长白山脉东部的长白山自然保护区(以下简称长白山)和位于长白山脉西部的吉林林学院蛟河实验林场东大坡自然保护区(以下简称蛟河)的红松阔叶林，研究了红松阔叶林中林冠空隙的自然干扰规律和不同树种对林冠空隙的更新、反应规律，在此基础上，对红松阔叶林的结构特征做了初步分析。 通过调查研究，摸清了红松阔叶林中林冠空隙干扰的基本规律，得到了红松阔叶林林冠空隙干扰状况的一些重要参数，这些参数包括：林冠空隙在红松阔叶林景观中所占的面积比例、林冠空隙的大小结构、林冠空隙的年龄结构、林冠空隙干扰的周转率、林冠空隙的分布格局、林冠空隙的形成方式、林冠空隙形成木的数量、林冠空隙形成木的直径结构、高度结构和腐烂状况等。与蛟河红松阔叶林相比。长白山红松阔叶林中林冠空隙在森林中所占的面积比例较大，林冠空隙的平均大小也较大，林冠空隙干扰的周转率较快。长白山红松阔叶林中的林冠空隙大多是由1～4株形成木形成的，而蛟河红松阔叶林中的林冠空隙则大多是由1株形成木形成的。长白山红松阔叶林中形成林冠空隙最重要的方式是掘根风倒，其次是折干，而蛟河红松阔叶林中形成林冠空隙最重要的方式是折干，其次是掘根风倒。红松阔叶林中林冠空隙的空间分布格局都是均匀或随机型的，这种均匀型或随机型格局的形成可能与红松阔叶林中林冠层大乔木树种的分布格局有关。长白山红松阔叶林中的林冠空隙大多是由红松、水曲柳、蒙古栎和紫椴四个树种形成的，而蛟河红松阔叶林中的林冠空隙则大多是由红松、沙松、枫桦和鱼鳞松四个树种形成的。红松阔叶林中的主林层树木在径级为40～80cm和高度为25～30m时形成林冠空隙的可能性最大。红松阔叶林中，不同林冠空隙形成木的腐烂情况不同。 通过调查研究，摸清了红松阔叶林中林冠空隙更新和树种反应的基本规律。树种在红松阔叶林林冠空隙及非林冠空隙林分中的数量特征不同，树种在林冠空隙内的总密度大于非林冠空隙林分中，而在林冠空隙内的总显著度小于非林冠空隙林分中。红松阔叶林中大多数树种在林冠空隙内的密度都大于其在非林冠空隙林分中的密度，但各树种在林冠空隙内比非林冠空隙林分中密度增加的程度不同；一般大乔木树种的显著度值是林冠空隙内小于非林冠空隙林分中，而中、小乔木的显著度值是林冠空隙内大于非林冠空隙林分中。同一树种在林冠空隙及非林冠空隙林分中的重要值不同，根据不同树种在林冠空隙及非林冠空隙林分中重要值位序的差值大小，分别将长白山和蛟河红松阔叶林中树种对林冠空隙干扰的反应分为反应强烈、反应中等和反应不明显三类。林冠空隙提高了红松阔叶林的物种丰富度，增加了其多样性，为不同特性物种的共存提供了可能。随着林冠空隙与非林冠空隙的交替动态变化，红松和阔叶树以及主林层和中下层树种的相对优势度或重要性亦发生交替变化，在林冠空隙阶段是以阔叶树和中下层的中小乔木相对占优势或较重要，而在非林冠空隙阶段则是以红松和主林层的大乔木树种相对占优势或较重要。林冠空隙的发生、发展及其随不同立地条件的变化，是红松阔叶林景观结构“微观”发生的重要机制。通过对蛟河红松阔叶林的研究表明：不同树种在林冠空隙内的更新密度随林冠空隙的大小和发育阶段的不同而发生不同的变化。各树种在林冠空隙内的更新密度随林冠空隙大小的变化呈单峰型反应，除沙松、紫椴和花楷槭的更新密度在林冠空隙大小为40～60m~2时最大外，其它树种的更新密度均在林冠空隙大小为20～40m~2时最大。不同树种的更新密度对林冠空隙发育阶段的反应有单峰型、双峰型和反应不明显三种类型。更多还原

【Abstract】 This thesis deals with gap dynamics in Korean pine broad—leaved forests in the Changbai Mountain and in Jiaohe, northeastern China. Natural disturbance regimes of gaps,tree species regeneration responses to gaps, and some structural characteristics of stands in the Korean pine broad —leaved forests were studied.The patterns of gap disturbances were investigated. Some parameters related to gap disturbance such as size and age structure of gaps,distribution patterns of gaps,diameter,height and decay class structure of gap makers, the numbers of gap makers forming a gap,turnover rate of gap disturbance, manners of gap formation as well as percentage of gap area in the Korean pine broad — forest landscapes were described and discussed in detail. Compared with those in the Korean pine broad — leaved forest in Jiaohe,the percentage of gap area in the Korean pine broad —leaved forest in the Changbai Mountain is greater, the average size of gaps is larger, the turnover rate of gap disturbance is faster. Most of the gaps in the Korean pine broad—leaved forest in the Changbai Mountain were formed by 1 — 4 gap makers; but in Jiaohe, they were mainly formed by one gap maker. In the Korean pine broad —leaved forest in the Changbai Mountain,gaps mostly resulted from uprooting treefall and then from stem breakage,while in Jiaohe,compared with uprooting treefall,stem breakage contributed more in the formation of gaps. The spatial distribution patterns of gaps in the Korean pine broad — leaved forests belong to the uniform or random types, which, to some extent, were caused by the distribution patterns of main big trees in the canopy layer. Major gap makers in the Korean pine broad — leaved forest in the Changbai Mountain were Pinus koraiensis, Fraxinus mandshurica, Quercus mongolica, and Tilia amurense,but those in Jiaohe were Pinus koraiensis, Abies holophylla,Betula costata,and Picea jezoensis. The probabity of making gaps was greatest when the trees in the Korean pine broad— leaved forests got D. B. H. 40 —80cm and height 25 —30m. Decay conditions of gap makers differed with species types.The quantitative characteristics of tree species in gaps differed from those in non—gap stand. The total density of all tree species in gaps is greater than that in non—gap stand .but, the total dominance of all tree species in gaps is smaller than that in non —gap stand. The densities of most tree species in gaps are greater than their correspondent densities in non — gap stand, but the degree of density increase in gaps for different species is different. Generally , the dominances of most of the big statured tree species in gaps are smaller than those in non —gap stand,while the dominances of middle or small statured tree species in gaps are greater than those in non —gap stand. The importance values of the same species in gaps and in non—gap stand are different. Based on the differences of orders of importance values of tree species in gaps and in non—gap stand,the tree species in the Korean pine broad — leaved forests in the Changbai Mountain and in Jiaohe were classified into three ecological groups respectively,i. e. the severe responsive(to gap disturbance)group,the moderate responsive(to gap disturbance) group, and the no significant responsive (to gap disturbance) group. Gaps enhanced the species richness, increased the species diversity, and made the coexistence of different species possible. With the alternation of gaps and non —gaps in the Korean pine broad —leaved forests.the relative dominance更多还原