林火干扰对兴安落叶松林土壤化学性质的影响

Effect of Fire on Soil Chemical Properties of Larix gmelini Forest in Daxing'an Mountains

以内蒙古大兴安岭兴安落叶松林火烧迹地为研究对象,并选择附近未火烧区作为对照区,分析比较了不同火烧强度干扰下,土壤化学性质的变化规律。结果表明:不同火烧迹地土壤全N和全K质量分数均比对照有所降低,差异显著(p<0.05),均呈现重度火烧区小于轻度火烧区,且均小于对照区的趋势;火干扰对土壤全P无显著影响,不同火烧迹地土壤全P质量分数与对照区基本保持在一个水平梯度内,无显著变化;不同火烧迹地土壤碱解N和速效P质量分数与对照相比均显著增加,且土壤碱解N质量分数随火烧强度变化呈现轻度火烧区大于重度火烧区,而土壤速效P质量分数则呈现出重度火烧区大于轻度火烧区,且均大于对照区的趋势;不同火烧迹地土壤速效K质量分数较对照相比都有所下降,但随火烧强度的大小变化无明显规律。

We investigated the chemical properties of forest soil in an unburned control and burned sites in the Daxing ’an Mountains of Northeastern China. The soil total N and total K were significantly lower in the two different years than those in the control,and showed a descending ranking of unburned control,light burned area,and heavy burned area. Fire disturbance has no significant effect on total soil P compared with the control. The soil total P in the different burned sites were basically kept within a range compared with the control. The soil available N and available P were significantly higher in the two different years than those in the control. Soil available N showed a ascending ranking of unburned control,heavy burned area,and light burned area,while soil available P showed a ascending ranking of unburned control,light burned area,and heavy burned area. Soil available K was decreased compared with the control in both two years,but there was no significant difference between the two fire intensities.