Pluer William T, Geohring Larry D, Steenhuis Tammo S, Walter M Todd
J Environ Qual. 2016 May;45(3):772-8. doi: 10.2134/jeq2015.06.0271.
Denitrifying bioreactors have been suggested as effective best management practices to reduce nitrate and nitrite (NO) in large-scale agricultural tile drainage. This study combines experiments in flow-through laboratory reactors with in situ continuous monitoring and experiments in a pair of field reactors to determine the effectiveness of reactors for small-scale agriculture in New York. It also compares the use of a typical woodchip media with a woodchip and biochar mixture. Laboratory results showed linear increase in NO removal with both increased inflow concentration and increased residence time. Average removal of NO in weekly monitoring of field reactors over the course of two growing seasons was 3.23 and 4.00 g N m d for woodchip and woodchip/biochar reactors, respectively. Removal of NO during two field experimental runs was similar to in situ monitoring and did not correlate with laboratory experiments. Factors that are uncontrollable at the field scale, such as temperature and inflow water chemistry, may result in more complex and resilient microbial communities that are less specialized for denitrification. Further study of other controlling variables, other field sites, and other parameters, including microbial communities and trace gas emissions, will help elucidate function and applicability of denitrifying bioreactors.
反硝化生物反应器已被建议作为减少大规模农业瓦管排水中硝酸盐和亚硝酸盐（NO）的有效最佳管理措施。本研究将流通式实验室反应器实验与原位连续监测以及一对田间反应器实验相结合，以确定反应器对纽约小规模农业的有效性。它还比较了典型木屑介质与木屑和生物炭混合物的使用情况。实验室结果表明，随着进水浓度和停留时间的增加，NO去除呈线性增加。在两个生长季节的田间反应器每周监测中，木屑反应器和木屑/生物炭反应器的NO平均去除量分别为3.23和4.00 g N m² d。两次田间实验运行期间的NO去除情况与原位监测相似，且与实验室实验无关。在田间尺度上无法控制的因素，如温度和进水水化学性质，可能会导致更复杂且有弹性的微生物群落，这些群落对反硝化作用的专一性较低。对其他控制变量、其他田间地点以及其他参数（包括微生物群落和微量气体排放）的进一步研究，将有助于阐明反硝化生物反应器的功能和适用性。
