双氰胺在不同温度下对碱性土尿素氮转化的影响  

Effects of Dicyandiamide on Urea Nitrogen Transformation in Alkaline Soil in Different Temperatures

作　　者：张露[1,2] 皮荷杰 周细红[1] 蒋朝晖[1] 曾清如[1] 

机构地区：[1]湖南农业大学资源环境学院,湖南长沙410128 [2]陕西省土地工程建设集团国土资源部退化及未利用土地整治工程重点实验室,陕西西安710075 [3]株洲市环境保护研究院,湖南株洲412007

出　　处：《水土保持通报》2015年第6期172-177,共6页Bulletin of Soil and Water Conservation

基　　金：农业部重大专项"湖南省重金属污染耕地修复及农作物种植结构调整"(农办财函〔2014〕28号)

摘　　要：[目的]为了提高氮素的利用效率,减少NO_3^-—N淋溶污染,本试验研究了硝化抑制剂双氰胺(DCD)对碱性土壤中氮素转化的影响,为氮素的合理高效利用,增加作物产量提供参考。[方法]采用实验室人工气候箱培养法,研究双氰胺在15,25和35℃不同温度下对山西省晋城市菜园土(碱性)的pH值、氨挥发量及NH_4^+—N和NO_3^-—N转化的影响。[结果]在碱性土壤中施加双氰胺后,其pH值高于对照,且pH值随土壤温度的升高而升高;同时碱性土壤中氨挥发量也随温度升高而增大,每升高10℃,氮素以氨气形式损失的增加率约为6.90%;而土壤NO_3^-—N量却随温度的升高有所下降,其变化趋势与土壤NH_4^+—N量变化相反,此外温度的升高可导致NH_4^+—N含量峰值的出现时间提前,每增加10℃提前约为1周左右。双氰胺的施加可减少了NH_4^+—N转化为NO_3^-—N的量。[结论]双氰胺的施加可减少碱性土壤中氮素转化为NO_3^-—N所带来的淋溶污染问题,且随温度的升高pH值、氨挥发量和NH_4^+—N量增加。[Objective]In order to increase the utilization efficiency of nitrogen,reduce the leaching pollution of nitrifying nitrogen,the study explored the effect of nitrification inhibitor DCD on nitrogen transformation in alkaline soils,which may provide a reference for rational and efficient use of nitrogen and increasing crop yields.[Methods]The laboratory artificial climate chamber culture was used to study the effects of DCD on pH value,ammonia volatilization,nitrifying nitrogen and ammonia nitrogen conversion of Jincheng City of Shaanxi Province（alkalinity）garden soils in different temperatures of 15℃,25℃and 35℃.[Results]The result indicated that the pH value with DCD was higher than the control,which increased with the temperature increasing.The ammonia volatilization increased with the temperature increasing in alkaline soil,so the temperature increase by 10℃,the increasing rate of nitrogen loss in the form of ammonia was about 6.90%.The nitrifying nitrogen content decreased with temperature increasing,whose variation was opposite with ammonia nitrogen content.Moreover,the peak time of ammonia nitrogen content with temperature increasing was about one week ahead with the increase of temperature by each 10℃.DCD reduced the conversion of ammonia nitrogen to nitrifying nitrogen.[Conclusion]DCD can reduce the leaching pollution problems by lowering the nitrogen conversion to nitrifying nitrogen,and the pH value,ammonia volatilization and ammo-nia nitrogen increase with the temperature increasing.

关 键 词：双氰胺 氮素 pH值 氨挥发 NO3^-—N NH4^+—N 

分 类 号：S158.5[农业科学—土壤学]