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森林发育对土壤理化性质有着重要的影响。在南亚热带,以杉木皆伐改造林地3个林龄段(3~5 a、7~9 a和10~11 a)的针阔混交林为研究对象,研究了土壤理化性质的变化特征以及不同理化性质指标之间的相关性。结果表明,土壤容重、总孔隙度、毛管孔隙度随林龄的增加呈上升趋势,而非毛管孔隙度和土壤通气度表现为先升高后降低。土壤pH值、有机质、全N、全P、全K、水解N、速效K随林龄的增加呈现出先降低后升高的趋势,而有效P处于下降的趋势。相关分析表明,不同林龄段针阔混交林的土壤容重主要取决于土壤有机质含量,自然含水量主要取决于毛管孔隙度;土壤有机质含量与全N和水解N相关性最高,土壤中绝大部分N素以有机态存在;而土壤有效P含量主要取决于土壤有机质含量,同时受土壤pH值影响也较大。
Forest development has an important impact on soil physical and chemical properties. In the South Asia subtropics, the coniferous-broad-leaved mixed forest with three ages (3 ~ 5 a, 7 ~ 9 a and 10 ~ 11 a) was used to study the changes of soil physical and chemical properties and their differences Physical and chemical properties of the correlation between indicators. The results showed that soil bulk density, total porosity and capillary porosity increased with age, but non-capillary porosity and soil aeration showed the first increase and then the decrease. Soil pH, total organic matter, total N, whole P, total K, hydrolyzed N and available K decreased first and then increased with the increase of forest age, while effective P was in a downward trend. The correlation analysis showed that the bulk density of the mixed forest of broadleaf and broadleaf forest varied with the soil organic matter content, and the natural water content mainly depended on the capillary porosity. The correlation of soil organic matter content with total N and hydrolyzed N was the highest, N is in the organic state; while the effective P content in the soil mainly depends on the content of soil organic matter, and is also greatly affected by the soil pH value.