为揭示土壤理化性质和土壤重金属的相关性，采用对角线法和环刀法对深圳市田头山自然保护区 3 个典型常绿阔 叶次生林样地进行土壤采集，并测定其主要理化性质和重金属含量。研究发现，0~20 cm 剖面层容重最小，土壤有机质、 全氮、碱解氮整体随土层深度增加而减小；理化性质与重金属间存在显著或极显著相关性。结果表明，与土壤物理性质相比，化学性质与重金属相关性密切，通过冗余分析得出全磷、 全氮、全钾、碱解氮、pH、有机质等是影响重金属含量的主要因子，通径分析进一步确定土壤理化性质对重金属活性的直接和间接效应。

In order to reveal the correlation between soil Physicochemical properties and soil heavy metals, the diagonal method and circular knife method were used to collect and determine the main physicochemical properties and heavy metal contents in three typical evergreen broad-leaved secondary forest sample plots in Tiantou Mountain Nature Reserve, Shenzhen. It was found that the soil bulk density of the 0~20 cm profile layer was the smallest, and the overall soil organic matter, total nitrogen and alkaline decomposition nitrogen decreased with increasing soil depth. At the same time, there was a significant or highly significant correlation between physicochemical properties and heavy metals. The results showed that chemical properties were closely correlated with heavy metals compared to soil physical properties. Redundancy analysis led to the conclusion that total phosphorus, total nitrogen, total potassium, alkaline soluble nitrogen, pH and organic matter were the main factors affecting heavy metal content. Passage path analysis further determined the direct and indirect effects of soil physicochemical properties on heavy metal activity.

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省级生态公益林效益补偿资金省统筹项目“珠三角城市森林生态效益监测与评估”（2020STC）；广东省林业科技创新平台项目“林业生态监测网络平台建设”（2021-KYXM-09，2021-KYXM-09）；深圳市野生动物救护中心项目“市级自然保护区生态监测”；深圳市规划和自然资源局项目“深圳市国家森林城市建设生态工程成效评估技术”