吉林蛟河针阔混交林树木生长的空间关联格局

以吉林蛟河21.12hm2(660m×320m)针阔混交林样地为对象,利用2009年和2014年森林生长观测数据,研究树木生长的空间自相关格局及其生境影响机制。在样地生境型划分结果的基础上,采用Ripley's L(r)函数分析不同生境型中树木种群空间分布特征;利用标记相关函数分析不同生境型中树木生长特征的空间关联格局。研究结果表明:(1)红松(生境型3:1—5m)、蒙古栎(生境型3:1—3m)、胡桃楸(生境型2:1—2m;生境型3:1—7m)、黄檗(生境型2:1—3m;生境型4:1—5m)、水曲柳(生境型3:1—2m;生境型4:1—2m)、瘤枝卫矛(生境型2:1—15m)在特定生境和空间尺度上呈随机分布,但空间格局仍以聚集性分布为主;其余10个物种则在全部0—30m尺度上呈聚集分布。(2)标记相关函数分析显示春榆、毛榛、色木槭、瘤枝卫矛和千金榆的径向生长至少在一个生境中表现出正相关格局;暴马丁香、胡桃楸、裂叶榆、瘤枝卫矛、水曲柳、紫椴、糠椴、毛榛、色木槭和白牛槭的径向生长至少在一个生境中表现出负相关格局;红松、黄檗、蒙古栎和簇毛槭的径向生长在全部尺度上均未检测到显著的空间关联格局。因此,不同树种径向生长的空间自相关特征不同,树种生长特征的空间关联格局具有明显的生境依赖性。

Spatial autocorrelation patterns of tree growth in a coniferous and broad-leaved mixed forest in Jiaohe of Jilin province

This study aimed to determine the spatial autocorrelation patterns of tree growth and the mechanisms influencing habitat heterogeneity. A dataset of observed forest growth was used, with data between 2009 and 2014 from a 21.12 hm² stem-mapped mixed forest plot (temperate coniferous and broadleaved forest) in Jiaohe, Jilin Province. Based on habitat type classifications, Ripley''s L(r) function was adopted to evaluate the spatial distribution characteristics of tree locations. A mark correlation function (MCF) was used to evaluate the spatial autocorrelation characteristics of tree growth. Our results showed that (1) Pinus koraiensis (habitat type 3: 1-5 m), Quercus mongolica (habitat type 3: 1-3 m), Juglans mandshurica (habitat type 2: 1-2 m; habitat type 3: 1-7 m), Phellodendron amurense (habitat type 2: 1-3 m; habitat type 4: 1-5 m), Fraxinus mandshurica (habitat type 3: 1-2 m; habitat type 4: 1-2 m), and Euonymus verrucosus (habitat type 2: 1-15 m) were randomly distributed at particular scales and for certain habitat types. Nonetheless, they mainly showed clumped distribution patterns. For ten other species, the spatial distribution of tree positions showed an aggregated pattern at a scale of 0-30 m. (2) The mark correlation function analysis indicated that the radial growth of Ulmus davidiana var. japonica, Corylus mandshurica, Acer mono, E. verrucosus, and Carpinus cordata were positively autocorrelated for at least one of the habitat types. In contrast, the radial growth of Syringa reticulata var. amurensis, J. mandshurica, Ulmus laciniata, E. verrucosus, F. mandshurica, Tilia amurensis, Tilia mandshurica, C. mandshurica, A. mono, and Acer mandshuricum were negatively autocorrelated at least in one of habitat types. Other species did not show any significant autocorrelations at any of the studied scales. Our results indicate that different species had different spatial autocorrelation characteristics of radial growth, as well as significantly different habitat dependencies.