摘要
为研究硝态氮在宁夏黄灌区灌於土中的基本运移规律,采用水平土柱进行硝态氮水平运移规律研究,并采用自制垂直土柱完成了硝态氮垂直运移规律研究。硝态氮水平运移规律研究表明:硝态氮运移与水分湿润峰迁移具有很好的一致性,随着硝态氮运移距离的增加,硝态氮浓度升高,并在湿润峰处累积;硝态氮浓度随含水量的增加而减少,并呈幂函数关系;硝态氮运移速率随运移距离增加而减小,且呈冥函数关系。硝态氮垂直运移实验表明:由于有机质和粘粒含量不同,各土层硝态氮穿透曲线差异较大;CXTFIT模型的拟合结果与实测结果相关性很好,说明可以使用CXTFIT模型进行土壤硝态氮运移预测和土壤硝态氮运移参数的测定。
Nitrate nitrogen（NO-3-N） transport has special patterns in anthropogenic-alluvial soil of Ningxia irrigation area.In this paper,we studied the NO-3-N transport characteristics using the horizontal and vertical soil columns.The results on NO-3-N horizontal transport experiment indicated that the NO-3-N horizontal transport followed very well with the soil moisture movement.With the increases of NO-3-N horizontal transport distance,the concentration of NO-3-N was higher,and reached the maximum at the interface of wetting front.The concentration of NO-3-N decreased with the increases of the soil water content,and their relationships could be fitted with a power function.The NO-3-N transport rate decreased with the increase of the NO-3-N horizontal movement distance,following a power function as well.Vertically,the NO-3-N breakthrough curve（BTC） significantly different along with the soil depths,as affected by the different content of the organic matter and the clay in different soil layers.The CXTFIT was used to simulate the breakthrough curve.Parameters obtained with CXTFIT fitted very well with the measured values,indicating that the CXTFIT model could be used for NO-3-N transport prediction in anthropogenic-alluvial soil of Ningxia irrigation area.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2011年第10期2046-2053,共8页
Journal of Agro-Environment Science
基金
黄河上游灌区农田退水污染控制与湿地生态修复关键技术研究与示范(2008ZX07212-004)
关键词
灌於土
硝态氮
水平运移
垂直运移
穿透曲线
anthropogenic-alluvial soil
nitrate nitrogen
horizontal transport
vertical transport
break through curve
