入侵植物薇甘菊对土壤主要温室气体排放的影响:真菌主导N2O排放与低CO2当量特征OA

To reveal the impact of plant growth on soil N2O and CO2 emissions,a combined field and pot experi-ment was conducted to study the soil greenhouse gas emissions of Mikania micrantha and its competing plants,Pueraria lobata var.thomsonii and Ipomoea batatas.The results showed that the CO2 equivalent emissions from the soil where M.micrantha grew were significantly lower than those from the soil where P.lobata var.thomsonii and I.batatas grew,indicating a lower greenhouse effect potential.The relative contribution of fungi to N2O emissions(79.3%)was significantly higher than that of bacteria(58.1%).The random forest model revealed that total soil nitrogen(TN),nitrate nitrogen(NO3--N),and ammonium nitrogen(NH4+-N)were the core driving factors of greenhouse gas emissions(explaining more than 11%),and were significantly positively correlated with CO2 equivalent emissions(R²=0.49-0.82).The greenhouse gas emission effect of the soil where M.micrantha grows is closely related to the choice of control species.Compared with the local plants P.lobata var.thomsonii and I.batatas,the soil where M.micrantha grows shows a lower greenhouse effect potential,which may be related to the different nitrogen utilization strategies and nitrogen cycling microbial community regulation mechanisms of different plants.This provides an important reference for the assessment of the ecological effects of invasive plants,but further validation is needed by combining more species and long-term observations.