论文部分内容阅读
通过对大兴安岭新林林业局 2 0年内不同年数间隔的 10块火烧迹地土壤进行调查取样和室内实验分析 ,发现不同年限、不同强度的火烧迹地土壤结构变化情况如下 :低、中强度火烧对土壤密度和孔隙度的影响不大 ,对土壤分散系数有一定影响 ;高强度火烧对土壤密度、孔隙度和分散系数的影响显著。降雨能使火烧迹地的土壤密度和分散系数升高、孔隙度下降。连年火烧使土壤密度比未烧林地下降 ,而孔隙度和分散系数升高。由此可见 ,高强度火烧对土壤结构破坏严重 ,而低中强度火烧对土壤坚实度和孔隙状况影响不大 ,但对土壤的保水保肥能力有显著影响。
Through investigation and sampling and laboratory experiment analysis of 10 burned-out soils with different annual intervals in Xinlin Forestry Bureau of Daxing’anling for 20 years, it was found that the structure of soil with different intensities of fire burned in different years was as follows: The effect of low and medium intensity fire on soil density And porosity have little effect on the soil dispersion coefficient; high-intensity fire has a significant impact on soil density, porosity and dispersion coefficient. Rainfall can increase the soil density and the dispersion coefficient of the burned area and decrease the porosity. After years of burning, the soil densities were lower than those of non-burning forests, while the porosity and dispersion coefficient increased. It can be seen that high-intensity fire has a serious damage to the soil structure, while low-medium-intensity fire has little effect on soil solidity and porosity but has a significant effect on soil water retention and fertilizer retention.