中文摘要：

2011年8月,在红松阔叶混交林2.55hm2的样地内,调查了42株倒木及其形成的坑和丘复合体的微立地特征及其植被更新状况,测定了丘顶、丘面、坑壁、坑底、完整立地5个微立地的土壤含水量、土壤温度、空气相对湿度和光合有效辐射.结果表明：在5个微立地中,丘顶的光合有效辐射最高（527.9μmol·m-2·s-1）,完整立地最低（58.7μmol·m-2·s-1）;丘顶的土壤温度最高（16.0℃）,坑底最低（13.3℃）;坑底的土壤含水量最高（34.6%）,丘面最低（0.5%）;完整立地的空气相对湿度最高（75.9%）,丘顶最低（68.0%）.形成坑和丘复合体的5个树种的频率大小依次是红松（42.9%）〉云杉（31.0%）〉白桦（16.7%）〉冷杉（7.1%）〉稠李（2.4%）.42株掘根倒木中,有2/3偏向西北方向.倒木体积与坑深度、坑长度、丘高度、丘宽度均呈极显著正相关,与丘厚度呈负相关.坑的宽度和长度分别与倒木的胸径呈显著和极显著正相关.不同微立地之间物种丰富度的大小顺序为完整立地〉坑〉丘;所有树种盖度的大小顺序依次为完整立地〉坑〉丘.

英文摘要：

An investigation was conducted in a 2.55 hm2 plot of Pinus koraiensis-dominated broad- leaved mixed forest to study the microsite characteristics of pit and mound formed by 42 treefalls and the status of vegetation regeneration on the microsites. The soil water content, soil temperature, rel- ative air humidity, and photosynthetically active radiation （PAR） on five microsites （mound top, mound face, pit wall, pit bottom, and intact forest floor） were measured. Among the five miros- ites, mound top had the highest PAR （527.9 μmol . m-2 . s-1 ） while intact forest floor had the lowest one （58.7 μmol .m-2 . s-1 ）, mound top had the highest soil temperature （ 16.0 ℃） but pit bottom had the lowest one （ 13.3 % ）, pit bottom had the highest soil water content （34.6%） but mound face had the lowest one （0.5 % ） , and intact forest floor had the highest relative air hu- midity （75.9%） but mound top had the lowest one （68.0%）. The frequency of forming pit/ mound complex by the tree species was decreased in the order of Pinus koraiensis （42.9%）〉Picea asperata （31. 0%） 〉 Betula platyphylla （16.7%） 〉 Abiesfabri （7. 1%） 〉 Prunus padus（2. 4% ）. Among the 42 treefalls, two-thirds of them were in northwest direction. The treefalls volume had significant positive correlations with pit depth, pit length, mound height, and mound width, but negative correlation with mound thickness. The treefall mean diameter at breast height had significant positive correlations with pit width （r=0. 328, P=0.017） and pit length （r=0. 527, P = 0）. The tree species richness at the microsites decreased in the order of intact forest floor 〉 pit 〉 mound, and the tree species coverage was in the sequence of intact forest floor 〉 pit 〉 mound.