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[目的]分析氮素在盐碱稻田内的动态变化及潜在环境影响。[方法]以松嫩平原典型苏打盐碱地水稻田为研究对象,采用田间试验方法研究了该区水稻田中的氮素动态变化及其对环境的潜在影响。[结果]试验区土壤属强碱土,CEC、C/N比值都较高,保肥能力差;2年试验期内,田表水中的盐碱化指标含量波动较大;试验初期总氮和氨氮浓度达到最高值,之后随时间的推移而下降,强降雨对其影响较大;硝态氮浓度出现峰值晚于总氮和氨态氮,之后随时间的推移而下降;试验期间,氨挥发损失占总氮损失的18.9%～28.8%;田面水中总氮浓度均高于国家地表水环境质量III类标准;农田退水中的非离子氨浓度较高,对下游查干湖鱼类养殖存在危害。[结论]为盐碱地治理和水体和渔业资源保护提供了理论依据。
[Objective] The research aimed to analyze the dynamic change and potential environmental impact of nitrogen in saline-alkali paddy fields. [Method] Taking the typical soda saline-alkali rice paddy field in Songnen Plain as the research object, the field experiment was conducted to study the dynamic changes of nitrogen and its potential impact on the environment in paddy fields. [Result] The soil in the test area was strongly alkaline earth with high CEC and C / N ratio and poor fertilizer holding capacity. During the two years of experiment, the content of salinization index fluctuated greatly in the field water. The total nitrogen and ammonia nitrogen Concentration reached the highest value, then decreased with the passage of time, heavy rainfall had a greater impact on it; the peak value of nitrate nitrogen appeared later than total nitrogen and ammonia nitrogen, and then decreased with the passage of time. During the experiment, ammonia volatilization loss Accounting for 18.9% -28.8% of the total nitrogen loss; the total nitrogen concentration in surface water is higher than the national standard III of surface water environmental quality; the concentration of non-ionic ammonia in farmland reclamation is high, which is harmful to the fish breeding in Chagan Lake downstream. [Conclusion] This provided a theoretical basis for salinization and protection of water and fishery resources.