生物炭施用对桂北桉树人工林土壤酶活性的影响

Effects of biochar application on soil enzyme activities in Eucalyptus plantations in North Guangxi

为探究土壤酶活性对生物炭输入的响应特征,以及为合理应用桉树枝条生物炭提供理论参考,该研究基于桂北桉树人工林田间试验,以桉树人工林采伐剩余物枝条为原料,在500℃条件下厌氧制备生物炭,施用质量分数分别为0(CK)、0.5%(T1)、1%(T2)、2%(T3)、4%(T4)和6%(T5)的桉树枝条生物炭,输入1 a后,分析了不同处理下土壤酶活性的变化特征。结果表明:(1)沿着土层垂直深度,土壤酶含量减小。(2)各土层脲酶、过氧化氢酶、β-葡萄糖苷酶和脱氢酶的含量随生物炭施用量的增加而增大,在生物炭施用量为6%时含量最高。(3)酸性磷酸酶、蔗糖酶、亮氨酸氨基肽酶和纤维二糖苷酶的含量随着生物炭施用量的增加呈现先增加后减少的趋势,其中酸性磷酸酶和亮氨酸氨基肽酶在生物炭施用量为2%时含量最高,蔗糖酶和纤维二糖苷酶则在生物炭施用量4%时含量最高。总体上,桉树枝条生物炭施用不同程度地提高了桉树人工林的土壤酶活性。该研究结果可为林业废弃物制备生物炭资源化利用途径及其在桉树人工林的应用提供科学依据。

To investigate the effects of different biochar applications on soil enzyme activities in Eucalyptus plantations in North Guangxi,and provide theoretical references for the rational application of biochar to Eucalyptus plantations.Based on field experiments,biochar was prepared anaerobically at 500℃from branches of Eucalyptus plantation harvesting residues,and with six treatment groups,such as 0(CK),0.5%(T1),1%(T2),2%(T3),4%(T4),and 6%(T5),to analyze the changes in soil enzyme activities under different application rates after one year importation.The results were as follows:(1)The soil enzyme content decreased gradually as the soil layer deepened.(2)In the same soil layer,the contents of urease,catalase,β-glucosidase and dehydrogenase increased with the increase of biochar application,and the highest contents were found at 6%of biochar application.(3)With the increase of biochar application,the contents of acid phosphatase,sucrase,leucine aminopeptidase and cellobioglucosidase showed a trend of first increasing and then decreasing.Acid phosphatase and leucine aminopeptidase had the highest contents at 2%of biochar application.Sucrase and cellobioglucosidase had the highest contents at 4%of biochar application.In general,the biochar application increased the soil enzyme activities of Eucalyptus plantations.The results of this study can provide a scientific basis for the application of forestry waste biochar in Eucalyptus plantations.