Ma Fang, Wang Shunzhong, Sang Weiguo, Ma Keming
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
Plants (Basel). 2024 Aug 22;13(16):2339. doi: 10.3390/plants13162339.
The investigation into the spatial distribution of living woody (LWD) and coarse woody debris (CWD) within forests represents a fundamental methodology for probing the inherent mechanisms governing coexistence and mortality within forest ecosystems. Here, a complete spatial randomness (CSR) null model was employed to scrutinize the spatial pattern, while canonical correspondence analysis (CCA) and the Torus-translation test (TTT) were utilized to elucidate the distribution patterns of LWD and CWD within warm-temperate deciduous broadleaf secondary forests in Dongling Mountains plot, northern China. The results reveal that both LWD and CWD exhibit an aggregated distribution as the predominant pattern in the Dongling Mountains plot, with the proportion and intensity of aggregation diminishing as spatial scale increases. Specifically, the aggregation intensity g demonstrates a significant negative correlation with abundance and maximum diameter at breast height (DBH). Notably, the g of LWD manifests a stronger correlation with the maximum DBH, whereas the g of CWD exhibits a greater association with the mortality rate. CCA outcomes suggest that elevation, convexity, and aspect significantly impact LWD distribution, whereas CWD distribution shows substantial negative correlations with elevation, convexity, slope, and aspect. TTT findings indicate that ecosystems characterized by a substantial presence of LWD also display a notable prevalence of CWD. Additionally, the majority of species exhibit no habitat preference, displaying neutral habitat connections and low ecological niche differentiation within the sampled plot.
对森林中活立木（LWD）和粗木质残体（CWD）空间分布的调查，是探究森林生态系统中共存和死亡内在机制的基本方法。在此，采用完全空间随机（CSR）零模型来审视空间格局，同时利用典范对应分析（CCA）和环面平移检验（TTT）来阐明中国北方东灵山样地暖温带落叶阔叶次生林中LWD和CWD的分布格局。结果表明，在东灵山样地，LWD和CWD均呈现聚集分布作为主要格局，且聚集比例和强度随空间尺度增加而减小。具体而言，聚集强度g与丰度和胸径最大（DBH）呈显著负相关。值得注意的是，LWD的g与最大DBH的相关性更强，而CWD的g与死亡率的关联更大。CCA结果表明，海拔、凸度和坡向对LWD分布有显著影响，而CWD分布与海拔、凸度、坡度和坡向呈显著负相关。TTT结果表明，以大量LWD为特征的生态系统中CWD也显著普遍。此外，大多数物种没有栖息地偏好，在采样样地内显示出中性的栖息地联系和低生态位分化。
