摘要
为探讨蓄水坑灌肥液入渗下土壤水氮运移特性,通过室内试验对湿润体内土壤水分、NH+4-N和NO3--N的运移分布规律及氨挥发特性进行了系统研究。结果表明,蓄水坑灌肥液入渗下土壤水分主要分布在20~80 cm深层范围,表层土壤含水率较低,土壤水分的扩散分布主要集中在前9 d,再分布过程中,深层土壤含水率的增幅大于表层;氨挥发主要发生在蓄水坑边壁界面,占氨挥发总量的72.41%,且最大日均氨挥发量出现在第7天,达34.08 mg/(m^2·d);NH+4-N主要分布在地表以下30~60 cm范围,再分布10 d内NH+4-N质量分数随时间的延长逐渐增加,且第7天增加较快,15 d后减小;NO3--N主要分布在土壤湿润锋边缘,再分布15 d内,土壤NO3--N质量分数均随时间的延长逐渐增加。蓄水坑灌肥液入渗下,可提高地表以下30~60 cm土壤水分和NH+4-N质量分数,减小土壤表层氨挥发损失,增强90~100 cm深层土壤的硝化作用。
Harvesting rainfall using pits for irrigation has become increasingly popular in northwestern China. In this paper we investigated the movement of water and nitrogen in soil under irrigation and fertilization from a water storage tank in laboratory at 30℃. The tank was a cylindrical wedge-shaped plexiglass with radius of 100 cm and height of 120, approximately twelfth of the storage pit used in the field. The results showed that the water was mainly within 20-60 cm depth of the soil and the soil surface was relatively dry. The infiltration of water from the pit into the soft took place in the first nine days, and water redistribution occurred mainly downwards. Ammonia volatilized mainly at the soil-pit interface, accounting for 72.41% of the total volatilization.The maximum daily ammonia volatilization was 34.08 mg/（m2·d）, peaking seven days after the infiltration. The ammonium was main- ly found in 30-60 cm depth of the soil, increasing monotonically in the first nine days and then decreasing from 15 days after the infiltration started. The nitrate was found in the wetting front, increasing from Day 1 to Day 15 after the infiltration started. In summary, irrigation and fertilization from the water storage pit increased water con- tent and ammonium within the soil in the depth of 30 cm to 60 cm, decreased surface ammonia volatilization, and enhanced nitrification in soil in the depth of 90 cm to 100 cm.
出处
《灌溉排水学报》
CSCD
北大核心
2017年第10期56-61,共6页
Journal of Irrigation and Drainage
基金
国家自然科学基金项目(51409184)
山西省青年科技研究基金项目(201601D202070)
高等学校博士学科点专项科研基金项目(20130402110008)
太原理工大学校基金项目(2013Z071)
关键词
蓄水坑灌
肥液入渗
水氮运移
氨挥发
water storage pit irrigation
fertilizer solution infiltration
soil water and nitrogen transport
ammonia volatilization
