青檀天然群落土壤成分及其对青檀生长的影响

对湖北省三潭风景区青檀（Pteroceltis tatarinowii）天然群落土壤主要元素进行测定,并通过因子相关分析,探讨了土壤成分与青檀生长指标之间的相关性,研究结果可为青檀野生资源的保护和合理利用提供科学依据。结果表明,土壤水溶性Ca2＋、Mg2＋平均质量分数为3.598和0.176 g·kg-1,速效钾、全氮、有效磷的平均质量分数分别是133.324 mg·kg-1、4.413 g·kg-1和3.569 mg·kg-1,有机质平均质量分数为3.295%。土壤水溶性Ca2＋与青檀生长指标之间无显著相关关系;土壤可溶性Mg2＋与乔木、灌木的丛生植株数量呈显著正相关,当Mg2＋浓度处于0.191~0.221 g·kg-1之间时,青檀的丛生植株数量大;全氮与青檀乔木平均高度、平均胸径呈极显著正相关,与单生植株数量呈显著负相关;有效磷与乔木平均高度和胸径呈显著正相关;速效钾与乔木丛生植株数量及乔木总数量呈显著正相关;有机质灌木冠幅呈显著正相关。按土壤成分可将青檀群落聚成3类,3个聚类组的土壤水溶性Mg2＋、全氮（TN）、速效钾（TK）、有效磷（TP）、有机质以及青檀乔木植株总数量存在着显著差异。

The soil composition of Pteroceltis tatarinowii natural community and its effect on the growth of plant

The main soil elements of Pteroceltis tatarinowii natural community in Santan scenic area of Hubei Province were measured,and the correlations between the soil composition and the growth indices of P.tatarinowii were tested.This study would guide the protection and utilization of wild P.tatarinowii.The results showed that the average concentration of water-soluble Ca2＋,Mg2＋ were 3.598 g/kg and 0.176 g/kg,respectively;the average concentration of available potassium（K）,total nitrogen（N）,available phosphorate（P） were 133.324 mg/kg,4.413 g/kg and 3.569 mg/kg,respectively;and that of organic matter was 3.295%.No significant correlation between water-soluble Ca2＋ and the growth indices was observed.However,the highly positive significant correlations between water-soluble Mg2＋ and the number of tree tillers and shrub tillers existed when the concentration of water-soluble Mg2＋ was from 0.191 g/kg to 0.221 g/kg.The data suggested highly positive significant correlation between total N and average height,diameter at breast height（DBH） of trees,while negative significant correlation between total N and the number of single trees.The data also suggested other positive significant correlations between： available P and average height,DBH of trees;available K and the number of tree tillers,the total number of trees;and organic matter and crown width of shrubs.According to the soil composition,the community could be clustered into three groups which had significant difference in water-soluble Mg2＋,total N,available K,available P and organic matter.Moreover,there was significant difference in the total number of trees of three groups.