不同强度火烧对杨树林碳、氮及其比值变化的影响

Effect of Different Fire Intensities on Poplar Grove's Carbon,Nitrogen and Its Ratio

以杨树人工林为研究对象,对不同强度火烧迹地土壤C、N含量及C/N值在不同土壤深度的变化进行了研究。结果表明:火烧降低了土壤有机碳的含量,低强度火烧使土壤水解氮的含量增加,在低土壤层C/N值减小,而在深土壤层C/N值趋于不变。林火对土壤碳氮含量产生了显著的影响。低强度、中强度和高强度火烧样地中有机碳均值大小依次为低强度、中强度、高强度。土壤有机碳含量与水解氮呈正相关。

Taking the poplars plantation as the object,the article focuses on the fluctuation of the content of C and N in the slash field under different fire intensities and the ratio of C to N in different depths of soil. According to the research results, the amount of organic carbon in soil has been decreased by way of burning;low intensity fire has rendered the amount of hydrolysable nitrogen increase;and the ratio of C to N decreases in low layers of soil while that keeps steady in deeper layers. Forest fire influences the content of carbon and nitrogen dramatically. Furthermore, the average amount of organic carbon in the sample fields tested respectively by low, moderate, and high intensity fire increases by degrees. Moreover,the research has found a positive correlation between the amount of organic carbon and that of nitrogen in soil.