COMPETITION IN OLD GROWTH KOREAN PINE FOREST

Korean pine(Pinus koraiensis) interspecilic competition and intraspecifie companioned with other species competition in old growth Korean pine forest in northeast China were studied using Hegyi's competition index model for individual tree.The results show that differences of competitive intensity exist in interspecific and intraspecific for Korean pine with an order of intraspecific ＞Abies nephrolepis Picea koraiensis Tilia amurensis Betula costat＞Acer mono ＞Ulnuts propinqua＞Populus davidiana,and that relationship of competitive index to indivdual size (in DBH) of objective tree follows closely multiplieate eqtuation and that competitive intensity gradually reduces with inereasing of individual size of objective tree, but it is tending towards stability after individual of objective tree inerease to specified size (DBH about 20 cm).It provided a serviceable approach for researches of intraspecific relationship in population ecology.

阔叶红松林树种间竞争关系及其营林意义

According to field investigation data,the intraspecific competition and interspecific competition of Pinus koraiensis in broad-leaved Korean pine mixed forest in Changbai Mountains were studied by using Hegyi’s competition index model for individual tree.The results showed that intraspecific competition intensity of Pinus koraiensis reduced with increase of diameter scale of trees.The order of competition intensity is:Pinus koraiensis-Fraxinus mandshurica>Pinus koraiensis-Quercus mongolica>Pinus koraiensis-Pinus koraiensis>Pinus koraiensis-Tilia amurensis>Pinus koraiensis-Acer mono>Pinus koraiensis-Tilia mandshurica>Pinus koraiensis-Acer mandshurica.The relationship between competition intensity and individual size of objective tree follows closely the equation CI =AD-B.Based on the relationship,competition intensity in the forest is simulated.At the same time,some conclusions and suggestions are proposed.It is proved that Hegyi′s competition model for individual tree can provide quantitative index for study on intraspecific and interspecific relationship in plant population ecology.

采伐对长白山阔叶红松林乔木竞争关系的影响

[目的]研究不同采伐方式与强度对阔叶红松林群落结构和功能的影响。[方法]通过调查乔木的胸径、树高以及在样方中的位置等指标,采用Hegyi单木竞争指数模型,对长白山地区受不同采伐方式以及强度干扰的阔叶红松林群落中乔木竞争强度进行定量分析。[结果]不同采伐方式和强度对阔叶红松林中乔木竞争强度有不同影响,低强度择伐后变化最小,皆伐后变化最大。不同林层间乔木竞争强度有明显差异,主林层<次林层<林下层。无论采伐方式与强度如何,红松的胸径与其竞争指数都严格服从CI=A(DBH)B的幂函数关系。采伐对红松种内竞争强度有重要影响,随着采伐强度的加大,红松种内竞争压力减小,红松幼树更新得到促进。[结论]采伐经营应保持17%以下的小强度择伐,而择伐时应选择那些胸径大且在竞争中占绝对优势的针、阔叶树种。

红松天然林种内和种间竞争关系的研究

基于穆棱林业局3块红松天然林标准地调查数据,采用竞争区域动态半径的概念确定了林分中有效竞争木,并利用Hegyi竞争指数对红松天然林的种内、种间竞争强度进行了定量分析。研究结果表明:红松的种内和种间竞争强度分别占总竞争强度的18.0%和82.0%,说明红松天然林种内竞争小,主要竞争来自种间。色木、云杉、冷杉林木个体高大,数量较多,在群落中占据一定优势,对红松的竞争压力较大。红松对象木胸径与竞争指数之间呈幂函数关系,随着红松胸径的增大,受到的竞争强度逐渐减小。当红松胸径小于25cm时,所受到的竞争压力较大;当胸径大于25cm时,竞争指数较小,并维持稳定。