Carbon dioxide (CO₂) and methane (CH₄) produced by denitrification bioreactors in processing agricultural surface runoff have contributed to increasing proportion of greenhouse gases (GHG) emissions. It is the first time to monitor and quantify the emission flux of CO₂ and CH₄ produced by laboratory-scale denitrification bioreactors which recycled waste Cunninghamia lanceolata sawdust (CLS) and industrial sludge (IS) as fillers to process simulated agricultural surface runoff. Sludge-water ratio, inflow rate and water flow direction are used as experimental factors to study the effect on the emission flux of CO₂ and CH₄. Results show that emission flux of CO₂ from denitrification bioreactors with different sludge-water ratio approached 20 mg m⁻²h⁻¹, simultaneously the average emission flux of CH₄ produced by all bioreactors was 1.785 mg m⁻²h⁻¹. The addition of sludge increased the emission flux of CH₄ and had no significant effect on the emission flux of CO₂. Increasing the inflow rate reduced the CO₂ emission flux from 21.57 to 1.27 mg m⁻²h⁻¹, and at the same time increased the CH₄ emission flux from 0.007 to 9.54 mg m⁻²h⁻¹. The gravity flow of wastewater reduced the emission flux of CO₂ and CH₄. The emissions of CO₂ and CH₄ from folded plate denitrification bioreactor with CLS and industrial sludge with a volume ratio of 1:2 can be reduced by 24.67% and 73.3%, respectively. There was no need to add special gas collection and treatment devices because CO₂ and CH₄ emission fluxes produced by the folded plate denitrification bioreactor and gravity denitrification bioreactor are not enough to increase the greenhouse effect. This study quantified the CO₂ and CH₄ produced by denitrification bioreactors filling CLS and IS, and provided a reference for future research on the gases produced by the denitrification process.

反硝化生物反应器在处理农业地表径流中产生的二氧化碳（CO ₂）和甲烷（CH ₄）导致温室气体（GHG）排放比例的增加。这是第一次监测和量化由实验室规模的脱硝生物反应器产生的CO ₂和CH ₄的排放通量，该反应器将杉木（Cunninghamia lanceolata）锯末（CLS）和工业污泥（IS）废料作为填料来处理模拟的农业地表径流。以污泥水比，入水率和水流方向为实验因素，研究了CO ₂和CH ₄排放通量的影响。。结果表明，不同污泥水比的反硝化生物反应器的CO ₂排放通量接近20 mg m ^-2 h ^-1，同时所有生物反应器产生的CH ₄的平均排放通量为1.785 mg m ^-2 h ^-1。污泥的添加增加了CH ₄的排放通量，而对CO ₂的排放通量没有显着影响。流入量的增加将CO ₂排放通量从21.57减少到1.27 mg m ^-2 h ^-1，同时CH ₄排放通量从0.007增加到9.54 mg m ^-2h ^-1。废水的重力流降低了CO ₂和CH ₄的排放通量。含CLS的折板式反硝化生物反应器和工业污泥的体积比为1：2时，CO ₂和CH ₄的排放量可分别减少24.67％和73.3％。由于折叠板式反硝化生物反应器和重力反硝化生物反应器产生的CO ₂和CH ₄排放通量不足以增加温室效应，因此无需添加特殊的气体收集和处理装置。这项研究量化了CO ₂和CH ₄ 由装满CLS和IS的反硝化生物反应器生产的产品，并为未来研究反硝化过程产生的气体提供了参考。