State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; Center for Environmental Monitoring and Scientific Research of Yangtze River Basin Ecology and Environment Administration, Ministry of Ecology and Environment of the People's Republic of China, Wuhan 430019, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Shandong Institute of Geological Survey, Jinan 250014, China.
Sci Total Environ. 2020 May 20;718:137417. doi: 10.1016/j.scitotenv.2020.137417. Epub 2020 Feb 19.
Dicyandiamide (DCD) is commonly used as nitrification inhibitors which has the potential to reduce nitrogen loss from paddy soils. In paddy systems, periphytic biofilms are commonly presented at the soil/water interface and show significant effects on nutrient cycling. However, the interaction between DCD and periphytic biofilms in paddy and subsequent effects on nitrogen cycling is unclear. In this work, microcosm experiments were carried out to study the interaction between the periphytic biofilms and DCD and the potential influence on nitrogen cycling from in paddy. Results showed that DCD affected the development of periphytic biofilms, while the presence of periphytic biofilms accelerated DCD degradation. Results also showed DCD application reduced nitrification potential mainly by inhibiting ammonia-oxidizing bacteria (AOB). Higher DCD dosage increased NH volatilization loss. However, presence of periphytic biofilm reduced the NH volatilization loss but increased denitrification. Our work contributes to a better understanding on the nitrogen cycling processes in paddy, and provides useful information for the improvement of nitrogen utilization efficiency and the control of non-point source pollution.
双氰胺（DCD）通常被用作硝化抑制剂，具有减少稻田氮损失的潜力。在稻田系统中，周丛生物膜通常存在于土壤/水界面，对养分循环有重要影响。然而，DCD 与稻田周丛生物膜之间的相互作用及其对氮循环的后续影响尚不清楚。在这项工作中，进行了微宇宙实验，以研究周丛生物膜和 DCD 之间的相互作用以及它们对稻田氮循环的潜在影响。结果表明，DCD 影响周丛生物膜的发育，而周丛生物膜的存在加速了 DCD 的降解。结果还表明，DCD 的应用主要通过抑制氨氧化细菌（AOB）来降低硝化潜力。较高的 DCD 用量增加了 NH 挥发损失。然而，周丛生物膜的存在减少了 NH 挥发损失，但增加了反硝化作用。我们的工作有助于更好地了解稻田中的氮循环过程，并为提高氮素利用效率和控制非点源污染提供了有用信息。
