| 引用本文: | 郭晗笑,申丽霞,樊耀,等.压力水头和肥液浓度对微润灌土壤水氮运移的影响[J].灌溉排水学报,0,():-. |
| GUO Han-xiao,SHEN Li-xia,FAN Yao,et al.压力水头和肥液浓度对微润灌土壤水氮运移的影响[J].灌溉排水学报,0,():-. |
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| 摘要: |
| 摘 要：【目的】探究微润灌溉水肥一体化条件下土壤水氮分布特征。【方法】通过室内土箱模拟试验，设置了2个压力水头（1 m和1.5 m）和3个氮肥（尿素）水平（0、500和1 000 mg/L），共6个处理。定时记录累积入渗量和湿润锋运移距离，132 h后测定了湿润体不同位置土壤含水率、铵态氮量、硝态氮量，研究了不同压力水头和施氮量对土壤水氮分布的影响。【结果】尿素肥液对微润管出流速率具有明显影响，累积入渗量与时间呈显著的线性相关，压力水头1.5 m、施氮水平0 mg/L处理累积入渗量最大，达到10.55 L，湿润锋运移距离也最远。与1 m压力水头处理组相比，1.5 m压力水头处理组土壤含水率、铵态氮量、硝态氮量均增大；入渗132 h，与500 mg/L氮肥入渗处理相比，1 m压力水头水平下，1 000 mg/L氮肥入渗处理土壤中铵态氮、硝态氮量较小，1.5 m压力水头水平下，1000 mg/L氮肥入渗处理土壤中铵态氮量、硝态氮量较多。【结论】增大压力水头显著增加了入渗速率、累积入渗量、湿润锋运移距离、土壤含水率、土壤中铵态氮量和硝态氮量；尿素肥液入渗限制了微润灌出流，提高了土壤中铵态氮量、硝态氮量，肥液浓度过大会限制尿素在土壤中的分解转化。 |
| 关键词: 微润灌溉;尿素肥液浓度;压力水头;累积入渗量;土壤含水率;铵态氮;硝态氮; |
| DOI： |
| 分类号:S275.9 |
| 基金项目:山西省自然科学(201701D121109,201801D121266)；山西省重点研发计划(201703D211020-2)；国家自然科学青年(51809189) |
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| Effects of pressure head and nitrogen application on water and nitrogen transport in soil under moistube irrigation |
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GUO Han-xiao, SHEN Li-xia, FAN Yao, NIU Shuang, YANG Mei, SUN Xue-lan, LIU Rong-hao
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College of water conservancy and Engineering,Taiyuan University of technology
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| Abstract: |
| 【Background】Moistube irrigation is a new type irrigation technology that delivers water and fertilizer to the root area of crops through semi-permeable membrane tube in a continuous flow from line source. The water and nitrogen migration and distribution are significant bases for the design and management of micro-irrigation system. At present, there are many studies on water and nutrient transport in planting experiments, but few studies on water and nitrogen transport through indoor simulation experiments. Therefore, the promotion of moistube irrigation technology has been seriously hindered. Urea is an organic fertilizer suitable for deep application and is suitable for combination with moistube irrigation. In order to provide data support for the development of moistube irrigation, the soil water and nitrogen transport law of urea fertilizer infiltration was studied.【Objective】To explore the distribution characteristics of soil water and nitrogen under the condition of water and fertilizer integration of moistube irrigation.【Method】Through the laboratory soil simulation test, six treatments including two pressure head treatments of 1m、1.5m and three nitrogen application levels of 0mg/L、500mg/L and 1000mg/L were set in the experiment. The cumulative infiltration amount and the migration distance of the wetting front were recorded regularly. After 132h, the soil moisture content, ammonium nitrogen and nitrate nitrogen content at different locations of the wetting body were measured, and the effects of pressure head and nitrogen concentration on the distribution of water and nitrogen in the soil were studied.【Results】Urea fertilizer limited the outflow of moistube, and the cumulative infiltration amount is significantly linearly correlated with the time. The pressure water head of 1.5 m and the nitrogen application level of 0 mg/L have the largest cumulative infiltration amount, reaching 10.55 L, and the wetting front diffuses furthest. The decrease of pressure head and the increase of the concentration of infiltration led to the decrease of the wetting front advance rate. Compared with the 1 m pressure head treatment group, the soil moisture content, ammonium nitrogen content and nitrate nitrogen content in the 1.5 m pressure head treatment group all increased. There was a peak of ammonium nitrogen in the soil, and the peak occurred at different time with different treatments, which would affect the accumulation of nitrate nitrogen and ammonium nitrogen in the soil. At 132 h of infiltration, at the level of 1m pressure head, the contents of ammonium nitrogen and nitrate nitrogen in the soil were smaller when compared with that of 500 mg/L. At the level of 1.5m pressure head, the contents of ammonium nitrogen and nitrate nitrogen in the soil were larger when compared with that of 500 mg/L.【Conclusion】Increasing the pressure head significantly increased the infiltration rate, cumulative infiltration amount, the migration distance of the wetting front, soil moisture content, the contents of ammonium nitrogen and nitrate nitrogen, while the infiltration of urea fertilizer limited the micro-irrigation flow and increased the contents of ammonium nitrogen and nitrate nitrogen, excessive concentration of fertilizer will limit the decomposition and transformation of urea in soil. |
| Key words: Moistube irrigation; Liquid concentration of urea fertilizer; Pressure head; Cumulative infiltration; Soil moisture content; Ammonium nitrogen; Nitrate nitrogen; |
