强还原与生物炭对土壤酶活性和温室气体排放的影响

本研究设置未修复对照(CK)、土壤强还原处理(RSD)、生物炭修复(BC)以及RSD与生物炭联合修复(RSD+BC),采用培养实验对比研究不同修复处理对设施蔬菜地土壤酶活性和温室气体(CO2和N2O)排放的影响.结果表明:相比CK,RSD和RSD+BC处理显著提高了β-葡萄糖苷酶(βG)、纤维二糖水解酶(CBH)、过氧...

Effects of reductive soil disinfestation and biochar on soil enzyme activities and greenhouse gas emissions

In this study, four treatments, i.e., soil without any amendment as control (CK), soil amended with 2% (w/w) rice straw (RSD), soil amended with 2% (w/w) biochar (BC), and soil amended with 2% (w/w) rice straw and 2% (w/w) biochar (RSD+BC), were performed to compare their influences on soil enzyme activities and greenhouse gas emissions. The results showed that the activities of β-glucosidase (βG), cellobiohydrolase (CBH), peroxidase (PEO), β-1,4-N-acetylglucosaminidase (NAG), acid phosphatase (AP), and the values of enzyme C:P and N:P were significantly increased in RSD and RSD+BC treatments compared with CK (P<0.05), but there was no significant difference on enzyme activities in BC treatment. Soil CO₂ emissions in RSD, BC, and RSD+BC treatments were increased by 10.6, 1.1, and 12.2times, respectively. Soil N₂O emission in RSD treatment was also significantly increased, but significantly decreased in BC and RSD+BC treatments (P<0.05). Compared with RSD treatment, RSD+BC treatment notably decreased N₂O emission and global warm potential (GWP) by 86.9% and 37.8%. Structural equation model analysis also indicated that βG and dissolved organic carbon (DOC) had a direct positive effect on soil CO₂ emission, and βG and CBH indirectly influenced CO₂ emission by affecting the DOC content. Moreover, soil NO₃^--N and NH₄⁺-N had a direct negative effect on N₂O emission. In summary, RSD+BC treatment was better in enhanced soil enzyme activities and decreased greenhouse gas emissions.