小兴安岭凉水典型阔叶红松林动态监测样地:物种组成与群落结构

Species composition and community structure of a typical mixed broadleaved-Korean pine (Pinus koraiensis) forest plot in Liangshui Nature Reserve, Northeast China

阔叶红松(Pinus koraiensis)林是我国东北东部山区的地带性顶极植被,按其群落特征和物种组成可分为南部红松林、典型红松林和北部红松林。依照BCI(Barro Colorado Island)50ha样地的技术规范,作者于2005年在典型红松林分布的黑龙江凉水国家级自然保护区建立了一块9ha的固定监测样地,并于2010年对样地内胸径≥1cm的木本植物进行了全面调查。结果表明,样地内的木本植物共有48种,独立个体数为21,355株(包括分枝数为34,021棵),隶属于20科34属。绝大部分种类属于长白山区系小兴安岭亚系,同时混生有一些亚热带成分。样地内所有个体的径级分布呈倒"J"型,群落自我更新良好。林冠层、亚冠层和中间层的径级分布均呈倒"J"型,林下层呈"L"型。主要树种大青杨(Populus ussuriensis)、红松、枫桦(Betula costata)、水曲柳(Fraxinus mandshurica)、红皮云杉(Piceakoraiensis)等的径级结构可分为近似于"正态"型、倒"J"型和"L"型3种类型。主要树种在样地的空间分布大多呈聚集分布,但大部分物种随着径级的增加聚集程度变小。树种分布与地形紧密关联,不同物种在不同径级表现出对生境有不同的偏好;红松和紫椴(Tilia amurensis)各径级的分布均与地形显著相关(P<0.05),而冷杉(Abies nephro-lepis)、花楷槭(Acer ukurunduense)、裂叶榆(Ulmus laciniata)、色木槭(Acer mono)的径级I(DBH<10cm)、II(10cm≤DBH<30cm)和枫桦、青楷槭(Acer tegmentosum)的径级I的分布与地形显著相关(P<0.05),且随着径级的增加,地形因子对其分布的影响显著减小。

The mixed broadleaved-Korean pine （Pinus koraiensis） forest （MBKF） represents the climax vegetation type of the eastern mountainous area of Northeast China. It is divided into three categories according to community structure and species composition, including southern MBKF, typical MBKF, and northern MBKF. To monitor long-term dynamics of the typical MBKF, we established a 9-ha plot following the field protocol of the 50 ha plot in Panama （Barro Colorado Island, BCI） in 2005 in Liangshui National Nature Reserve of Heilongjiang Province. All free-standing plant species with DBH （diameter at breast height） ≥1 cm were mapped, tagged, and identified to species in the plot. In the 2010 census, we documented 48 woody species with 21,355 individuals, belonging to 34 genera and 20 families. Most of the species belong to the Changbai Mountain plant flora, with a minor subtropical plant species component. The DBH distribution of all individuals showed a reversed ＂J＂ type, indicating well regenerated for the community. The DBH distribution for the canopy, sub-canopy, and middle layers and the understory layer showed the reversed ＂J＂ and ＂L＂ distributions, respectively. The DBH pattern of the nine dominant species can be classified into three categories： approximate normal, reversed ＂J＂, and ＂L＂ distribution. Spatial pattern analysis showed that the major tree species were aggregated, and aggregation intensity decreased as DBH increased. Further analysis showed that spatial distribution was closely related to topography and varied with DBH classes. For example, the distribution of Pinus koraiensis and Tilia amurensis was significantly affected by topography （P 0.05）; however, the distribution of Abies nephrolepis, Acer ukurunduense, and Ulmus laciniata correlated significantly with topography at diameter classes of I （DBH 10 cm） and II （10 cm ≤ DBH 30 cm）. The distribution of Betula costata and Acer tegmentosum was also significantly correlated with topography at a diameter class I （P 0.05）. Overall, the impact of the topographic gradient on species distribution decreased significantly as DBH class increased.