【摘要】 2018年3月份，在广西南丹县山口林场9、17、25、37年生秃杉（Taiwania flousiana）人工林中，分别选择邻近分布、立地条件基本一致地段，各设置3块20 m×20 m的样地；在每块标准地内按S形随机设置5个代表性采样点，按照土层深度（h）0<h≤20 cm、20 cm<h≤40 cm分层采集土壤样品，将相同样地同一土层样品混合，晾干并粉碎过筛后，测定土壤化学性质（土壤的pH、有机质质量分数、全氮质量分数、全磷质量分数、全钾质量分数、水解氮质量分数、有效磷质量分数、速效钾质量分数）;用100 cm³环刀采集原状土壤，测定土壤物理性质（土壤的含水量、密度、孔隙度、持水量）;依据试验测定结果，采用单因素方差分析法分析不同林龄秃杉人工林各土层土壤理化学性质的差异及林龄对秃杉人工林土壤理化性质的影响。结果表明：（1）不同林龄，土壤密度为0.852～1.011 g·cm^-3、总孔隙度为53.69%～78.48%、最大持水量为53.11%～78.48%,同层土壤总孔隙度、最大持水量均随林龄增加而增加，土壤密度则呈现相反的变化趋势。（2）同层土壤有机质质量分数、全氮质量分数、全磷质量分数、水解氮质量分数，均随林龄增加逐渐升高，土壤速效磷质量分数、速效钾质量分数总体也随林龄增加呈增加趋势，土壤pH则随林龄增加逐渐下降。（3）相关性分析显示，秃杉人工林土壤密度，与总孔隙度、最大持水量、主要养分指标均呈现极显著负相关；有机质质量分数，与土壤氮素、磷素、钾素（除全钾）呈极显著或显著相关，与pH呈极显著负相关。（4）综合试验研究结果，秃杉人工林的生长过程，能够改善土壤结构和水分状况，提高土壤有机质质量分数、主要养分质量分数。更多还原

【Abstract】 In March 2018, three 20 m×20 m sample plots, adjacent and have same stand conditions, were set up in each of the 9-, 17-, 25-, and 37-year-old plantations of Taiwania flousiana in Shankou Forestry, Nandan County of Guangxi, respectively. Five representative sampling points were randomly set up using S-shape within each standard plot. Soil samples were collected in layers according to the depth of soil layer(h) 0<h≤20 cm, 20 cm<h≤40 cm, then the samples from same soil layer were mixed in the same place, dried and crushed through sieve, and then the soil chemical properties(pH, organic matter, total nitrogen, total phosphorus, total potassium, hydrolyzed nitrogen, effective phosphorus and fast-acting potassium) were determined. The original soil was collected with a 100-cm~3 ring knife to determine the physical properties of the soil(soil water content, density, porosity and water holding capacity). With the results of the experiments, one-way ANOVA was used to analyze the differences in soil physicochemical properties of different soil layers and the effect of forest age on soil physicochemical properties of Taiwania flousiana plantations. The results showed that:(1) The soil density ranged from 0.852 to 1.011 g/cm~3, total porosity from 53.69% to 78.48%, and maximum water holding capacity from 53.11% to 78.48% at different stand ages, and the total porosity and maximum water holding capacity of the same soil layer increased with increasing stand age, while the soil density showed an opposite trend.(2) The contents of soil organic matter, total nitrogen, total phosphorus, and hydrolyzed nitrogen in the same layer gradually increased with increasing forest age, while those of soil fast-acting phosphorus and fast-acting potassium in general also showed an increasing trend with increasing forest age, and soil pH gradually decreased with increasing forest age.(3) By correlation analysis, soil density of T. flousiana plantation showed highly significant negative correlation with total porosity, maximum water holding capacity and major nutrient indexes; organic matter mass fraction showed highly significant or significant correlation with soil nitrogen, phosphorus and potassium(except total potassium), and highly significant negative correlation with pH.(4) The comprehensive experimental research results showed that the growth process of T. flousiana plantation could improve the soil structure and moisture status, and increase the soil organic matter content and major nutrient contents.更多还原