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为了阐明木兰围场天然次生林优势种群的结构和动态特征,对群落乔木层组成以及优势种群的径级结构、静态生命表、存活曲线、死亡曲线、生存函数和时间序列预测等进行研究.结果表明:群落乔木层有9个种群,其中,五角枫、蒙古栎、糠椴和白桦种群为群落的优势种群;五角枫和糠椴种群存活曲线接近于Deevey-Ⅱ型,蒙古栎种群存活曲线趋于Deevey-Ⅲ型,白桦种群存活曲线为Deevey-Ⅱ型;随着径级的增加,各优势种群的死亡率和消失率曲线呈现相似的变化趋势,五角枫、蒙古栎、糠椴种群的消失率和死亡率分别在Ⅳ、Ⅰ和Ⅰ径级下出现最大值,而白桦种群在各径级呈现稳定的变化趋势;4种生存函数曲线分析表明,五角枫、蒙古栎和糠椴种群具有前期锐减、中后期相对稳定的特点;白桦种群数量波动不明显,具有较稳定的特点.种群数量的时间序列预测表明,白桦种群小径级(Ⅰ~Ⅱ级)个体数量逐渐减少,种群未来有趋于衰退的趋势,五角枫、蒙古栎和糠椴种群趋于相对稳定.推测该次生林将逐步演替为以五角枫、蒙古栎和糠椴为主要树种的天然次生林.
In order to elucidate the structure and dynamic characteristics of dominant populations in natural secondary forests of Mulanweichang, the study was conducted on the composition of tree layers and the diameter structure, static life table, survival curve, death curve, survival function and time series prediction of the dominant tree species in the community.The results showed that: There were 9 populations in the arbor layer. Among them, the population of Pealous Maple, Quercus mongolica, Tilia mandshurica and Betula platyphylla was the dominant species in the community. The survival curves of Pealous oak and Tilia amurensis were close to Deevey-Ⅱ and the survival curves of Quercus mongolica population tended to Deevey -Ⅲ, the survival curve of Betula platyphylla population was Deevey-Ⅱ type. With the increase of diameter class, the mortality and vanishing rate curves of all the dominant species showed a similar trend. The disappearance rate of population of A. pentaphylla, Quercus mongolica, The mortality of Betula platyphylla, Quercus mongolica, Quercus mongolica and Tilia mandshurica were the highest in the order of IV, I and I, respectively. However, the population of Betula platyphylla showed a stable trend in all diameter classes. , And relatively stable in the middle and late stages.The population of Betula platyphylla was not obvious and stable in nature.The time series prediction of the population showed that the population of Betula platyphylla (Ⅰ ~ Ⅱ level), the population tends to decay in the future, and the populations of A. pseudoacacia, Quercus mongolica and Tilia mandshurica tend to be relatively stable, and it is inferred that the secondary forest will be gradually replaced by Pelargonium sibirica, Quercus mongolica and bran Linden as the main tree species of natural secondary forest.