云南松林土壤水文特征对计划烧除的响应

为探究计划烧除对云南松林土壤水文特征的影响，为计划烧除后森林生态系统服务功能评价提供依据，以云南省新平县实施多年计划烧除的云南松纯林为研究对象，设立20 m×20 m计划烧除样地和不进行计划烧除的自然对照样地各3块。2019年2月实施计划烧除作业，进行样地调查、火烧强度和枯落物储量调查，2020年6月采集土样，测定土壤物理、化学性质和土壤入渗性能。结果表明，计划烧除后土壤容重增加且在0~10 cm土层差异显著；毛管孔隙度和总孔隙度减少但差异不显著；有机质减少并在0~20 cm土层差异显著。计划烧除后土壤自然含水率、饱和持水率、毛管持水率和田间持水量减少但差异不显著；吸湿水量减少并且在0~20 cm土层差异显著。计划烧除后土壤初渗速率、土壤平均入渗速率和土壤稳定入渗率减少；土壤初渗速率和平均入渗速率在不同样地0~20 cm土层差异显著。计划烧除对土壤稳定入渗率的显著影响因素为土壤容重、孔隙度、有机质和饱和持水率。说明计划烧除后云南松林土壤持水性能下降，入渗性能下降，对于入渗性能的影响主要是源于土壤理化性质的改变。

Response of Soil Hydrological Characteristics to Prescribed Fire in Pinus yunnanensis Forest

The influence of prescribed fire on soil hydrological characteristics in Pinus yunnanensis forest was explored to serve as scientific basis of evaluating forest ecosystem services after prescribed fire. Series of prescribed fire were conducted on the Pinus yunnanensis forest in Xinping County during the past years. Six plots with size of 20 m×20 m were selected to investigate soil hydrological characteristics which included 3 in unburned forest and 3 in burned forest. In February 2019, the site investigation, fire intensity and litter storage were investigated after prescribed fire. In June 2020, soil samples were collected to determine soil physical and chemical properties and infiltration performance. The results showed that the bulk density of soil increased significantly in 0-10 cm soil layer after prescribed fire; the capillary porosity and total porosity decreased but not significantly; the organic matter decreased significantly in the 0-20 cm soil layer. Natural moisture content, saturated water capacity, capillary water capacity and field capacity decreased but not significantly after prescribed fire; hygroscopic water decreased significantly in 0-20 cm soil layer. After prescribed fire, the initial infiltration rate, average infiltration rate and stable infiltration rate descended; the initial infiltration rate and average infiltration rate had a significant difference in the 0-20 cm soil layer. Soil bulk density, porosity, organic matter and saturated water capacity were noticeable factors affecting the stable infiltration rate after prescribed fire. After conducting prescribed fire, soil water-holding capacity and infiltration capacity of Pinus yunnanensis forest were both lowed, which were mainly due to the change of soil physical and chemical property.