基于大型渗漏池监测的褐潮土农田水、氮淋失特征  

Characteristics of Field Water and Nitrogen Leaching in a Haplic Luvisol Soil Based on Large Lysimeter

作　　者：张亦涛[1,2] 王洪媛[1,2] 刘宏斌[1,2] 任天志[3] 

机构地区：[1]中国农业科学院农业资源与农业区划研究所,北京100081 [2]农业部面源污染控制重点实验室,北京100081 [3]农业部环境保护科研监测所,天津300191

出　　处：《中国农业科学》2016年第1期110-119,共10页Scientia Agricultura Sinica

基　　金：国家公益性行业(农业)科研专项(201003014)

摘　　要：【目的】明确华北平原褐潮土农田典型种植模式下水分和氮素的输入及淋失特征,阐明施氮量对淋失水质的影响,为从源头减少氮素淋失、防控农田面源污染提供科学依据。【方法】2007—2012年在"国家褐潮土土壤肥力与肥料效益长期监测基地"上,针对玉米单作种植模式,设置不同施氮梯度(不施氮CK,优化施氮T1,习惯施氮T2),利用"渗漏池"监测玉米生育期间土壤水分和氮素淋失过程,同时利用田间小气候气象站监测降雨发生过程,并详细记录灌溉事件。【结果】降雨和灌溉发生在4—10月,淋失发生在5—11月,相对降雨和灌溉时间有所滞后。年际间降雨量差异较大(134—525 mm),除2009年降雨少、无灌溉且未监测到淋失事件以外,其他年份水分输入总量均高于500 mm,并均监测到淋失事件。施氮处理比不施氮处理的淋失发生次数和淋失水量均有所减少,其中CK共发生淋失37次,淋失水量422 mm,T2共发生淋失31次,淋失水量310 mm。5年监测期间,灌溉和降雨携带的全氮共计157 kg·hm^(-2),其中可溶性总氮106 kg·hm^(-2),但年际间差异较大(7.53—34.1 kg·hm^(-2));灌溉和降雨携入氮量越多的年份,任一处理的氮素淋失量明显高于其他年份相同处理。硝态氮是淋失水中的主要氮素形态,并且施氮量越高,淋失水中硝态氮比重越大;无论是单次淋失事件还是年度淋失总量,T2淋失的可溶性总氮和硝态氮均明显高于CK和T1。CK和T1处理5年内全部淋失事件中的硝态氮平均浓度分别低于2.0、5.0mg·L^(-1),而T2处理的5年31次淋失事件中硝态氮浓度平均为29.5 mg·L^(-1),超过地下Ⅲ类水标准(20 mg·L^(-1))的次数有15次,最高浓度达79.0 mg·L^(-1)。【结论】灌溉和降雨是导致淋失的主要原因,输入的水量越多,越易发生淋失,硝态氮是淋失水中的主要氮素形态;年际间,氮素淋失量与灌溉和降雨携入的氮量呈正相关关系,灌溉和降雨�【Objective】The aim of this article was to determine clear characteristics of input and leaching of water and nitrogen under a typical farmland planting system in the North China Plain, and clarify the effect of N fertilizer on leaching water quality, which was eventually to provide a scientific basis for reducing nitrogen leaching from the source and prevention farmland ofnon-point source pollution. 【Method】 The experiment was set in the ＂Key Experimental Station on Ecological Environment of Drab Fluvo-aquic Soil in Changping, Ministry of Agriculture＂ for maize monoculture from 2007 to 2012, including three nitrogen gradients（no nitrogen CK, optimize nitrogen T1 and traditional nitrogen T2）. A large lysimeter was used to monitor the process of leaching of soil water and nitrogen during maize growth, at the same time the field microclimate stations were used to monitor the process of precipitation, while detailed irrigation events were also recorded. 【Result】The result showed that the precipitation and irrigation mainly occurred in April to October of every year. And leaching mainly occurred in May to November, which was later than the precipitation and irrigation. Annual precipitation was different among the five years（134-525 mm）. Precipitation in 2009 was less with no irrigation and resulted in no leaching events, while total water input was higher than 500 mm/year in other years leading to leaching events. Leaching occurrence frequency and water amount in the treatment of nitrogen application decreased compared to no nitrogen application, CK had 37 leaching events with a water volume of 422 mm while T2 had 31 leaching events with a water volume of 310 mm. Total nitrogen in irrigation and precipitation was 157 kg·hm^-2 and the dissolved total nitrogen was 106 kg·hm^-2 , while annual total nitrogen in irrigation and precipitation was different among the five years（7.53-34.1 kg·hm^-2 ）. For one year, the more nitrogen in irrigation and precipitation, the more nitrogen leaching for t

关 键 词：降雨 施氮 可溶性总氮 硝态氮 淋失 水质 

分 类 号：S158[农业科学—土壤学]