Nitrate attenuation during river bank infiltration is the key process for reducing nitrogen pollution. Temperature is considered to be an important factor affecting nitrate attenuation. However, the magnitude and mechanism of its impact have not been clear for a long time. In this study, the effects of temperature and temperature gradient on the nitrate denitrification rate were investigated via static batch and dynamic soil column simulation experiments. The results showed that temperature had a significant effect on the denitrification rate. Temperature effects were first observed in denitrifying bacteria. At low temperatures, the microorganism diversity was low, resulting in a lower denitrification rate constant. The static experimental results showed that the denitrification rate at 19 °C was approximately 2.4 times that at 10 °C. The dynamic soil column experiment established an exponential positive correlation between the nitrate denitrification decay kinetic constant and temperature. The affinity of denitrifying enzymes for nitrate in the reaction substrate was ordered as follows: decreasing temperature gradient (30 °C → 10 °C) > zero temperature gradient (10 °C) > increasing temperature gradient condition (0 °C → 10 °C). This study provides a theoretical basis for the biogeochemical processes underlying river bank infiltration, which will help aid in the development and utilization of groundwater resources.

河岸入渗过程中硝酸盐的衰减是减少氮污染的关键过程。温度被认为是影响硝酸盐衰减的重要因素。但其影响的大小和机制长期以来尚不清楚。本研究通过静态批量和动态土柱模拟实验研究了温度和温度梯度对硝酸盐反硝化率的影响。结果表明，温度对反硝化率有显着影响。温度效应首先在反硝化细菌中观察到。在低温下，微生物多样性较低，导致反硝化速率常数较低。静态实验结果表明，19℃时的反硝化率约为10℃时的2.4倍。动态土柱实验建立了硝酸盐反硝化衰减动力学常数与温度之间的指数正相关关系。反硝化酶对反应底物中硝酸盐的亲和力顺序为：温度梯度递减（30℃→10℃）>零温度梯度（10℃）>温度梯度递增条件（0℃→10℃） ）。该研究为河岸入渗生物地球化学过程提供了理论依据，有助于地下水资源的开发利用。