内蒙古大兴安岭典型混交林倒木空间点格局分析

依托内蒙古大兴安岭生态站,采用点格局分析法,对比分析兴安落叶松白桦、山杨白桦、白桦兴安落叶松3种典型混交林内不同树种及不同径级倒木分布格局。结果表明:(1)兴安落叶松白桦与白桦兴安落叶松混交林内倒木分布格局均呈显著聚集分布,山杨白桦混交林内倒木分布格局整体表现为随机分布;(2)3种混交林内兴安落叶松树种倒木均趋于随机分布,而白桦和山杨倒木以聚集分布为主,其中,白桦与兴安落叶松树种在白桦兴安落叶松混交林内1~23m分析尺度呈显著性负相关,在兴安落叶松白桦混交林内无显著关系,山杨与白桦树种在1~7m分析尺度存在较强烈的竞争,其余尺度无显著关系;(3)3种典型混交林内不同径级倒木分布格局均不同,大径级倒木以随机分布为主,中小径级倒木均为显著聚集分布,其中,大径级对中小径级倒木、中径级对小径级倒木均在小分析尺度存在较强烈的竞争。

Spatial Point Pattern Analysis on Typical Mixed Forest Fallen Wood in the Forest of Inner Mongolian Greater Khingan Mountains

Relying on the Ecological Station of Inner Mongolian Greater Khingan Mountains, this paper studied different tree species and different tree diameter fallen wood distribution patterns in three typical mixed forests including Larix gmelinii-Betula platyphylla mixed forest, Populus davidiana-Betula platyphylla mixed forest and Betula platyphylla-Larix gmelinii mixed forest through the method of point pattern analysis. The results show that:(1) the fallen wood distribution pattern in both Larix gmelinii-Betula platyphylla mixed forest and Betula platyphylla-Larix gmelinii mixed forest present an aggregated distribution. While in the Populus davidiana-Betula platyphylla mixed forest, it presents a random distribution.(2) the Larix gmelinii fallen wood in three typical mixed forests tends to be a random distribution, while the Betula platyphylla fallen wood and Populus davidiana fallen wood are mainly with aggregated distribution. The Betula platyphylla and the Larix gmelinii in Betula platyphylla-Larix gmelinii mixed forest exist a large scale of competition in the 1-23 m scale and they have no significant distribution relationship. The Populus davidiana and the Betula platyphylla have a strong competition between each other in the 1-7 m scale, while it has no significant distribution relationship in the large scale.(3) the distribution patterns of different tree diameter fallen wood in three mixed forest are different. Large diameter tree is mainly with random distribution. Both the small and medium-sized diameter tree species present an aggregated distribution. The large scale diameter fallen wood and the small and medium-sized diameter fallen wood have a strong competition in small scale, as well as the medium-sized diameter fallen wood and small scale diameter fallen wood.