摘要
红壤坡耕地氮磷淋溶不仅造成土壤肥力的下降,而且已成为农业面源污染的重要来源。该研究通过室内土柱淋溶试验,采用间歇淋溶法研究坡耕地裸露红壤和稻草秸秆覆盖红壤2种处理下氮素与磷素的淋溶特征。结果表明:对氮素而言,无论是8次间歇淋溶还是单次淋溶过程,总氮及硝态氮、铵态氮、有机氮等各形态氮素浓度总体均呈现减小的趋势,在淋溶初期无论有无覆盖土壤的淋溶液中总氮浓度都很高(在20 mg/L左右),硝态氮是氮素淋溶的主要形态(有无覆盖分别占68.3%和67.9%);对磷素而言,淋溶液中总磷浓度均很低(在0.1 mg/L以下),且在淋溶过程中其浓度大小呈波动状态;与裸露红壤相比,秸秆覆盖处理下淋溶液的总氮和总磷累积量分别可减少19.4%和23.3%,秸秆覆盖措施能够抑制红壤坡耕地氮磷的淋溶。该研究可为减少红壤坡耕地氮磷损失,防控面源污染提供参考。
Nitrogen and phosphorus leaching in red soil slope cropland not only caused the decline of soil fertility,but also became an important source of agricultural non-point source pollution.The leaching characteristics of nitrogen and phosphorus under the two treatments of bare red soil and straw mulching red soil in the slope cropland were studied by laboratory simulation tests with soil column.The results showed that for nitrogen,no matter during the eight intermittent leaching processes or the single leaching process,the concentration of total nitrogen(TN)and nitrate nitrogen(NO3--N),ammonium nitrogen(NH4+-N)and organic nitrogen all showed a decreasing trend.At the initial stage of leaching,the concentration of TN was very high which was about 20 mg/L and NO3--N was the main form of nitrogen leaching.The rates NO3--N from bare soil and mulching soil accounted for 68.3%and 67.9%respectively.For phosphorus,the concentration of TP in the leaching solution was very low which was below 0.1 mg/L and its trend was fluctuating during the leaching process.Compared with the bare red soil,the total accumulation amount of TN and TP in the leaching solution from the straw mulching treatment could be reduced by 19.4%and 23.3%respectively.It showed that the straw mulching measures could inhibit the leaching of nitrogen and phosphorus in the red soil slope cropland.This study could provide a reference for reducing the loss of nitrogen and phosphorus in red soil slope cropland and preventing and controlling non-point source pollution.
作者
欧阳祥
莫明浩
计勇
聂小飞
温英英
OUYANG Xiang;MO Minghao;JI Yong;NIE Xiaofei;WEN Yingying(College of Water and Ecological Engineering,Nanchang Institute of Technology,Nanchang 330099,China;Jiangxi Institute of Soil and Water Conservation,Nanchang 330029,China;Jiangxi Provincial Key Laboratory of Soil Erosion and Prevention,Nanchang 330029,China)
出处
《环境科学与技术》
CAS
CSCD
北大核心
2019年第11期40-46,共7页
Environmental Science & Technology
基金
国家自然科学基金项目(41501300,41761060,41601297)
江西省青年科学基金项目(20161BAB216148)
江西水利科技项目(KT201718,KT201721)
江西省重点研发计划项目(20192BBGL70043).
关键词
淋溶
氮素
磷素
土柱
坡耕地
红壤
秸秆覆盖
leaching
nitrogen
phosphorus
soil column
slope cropland
red soil
straw mulching
作者简介
欧阳祥(1995-),男,硕士研究生,主要从事水资源水环境研究,(电子信箱)871889311@qq.com;通讯作者:莫明浩,男,教授级高级工程师,博士,主要从事水土保持与生态环境研究,(电子信箱)mominghao@126.com。
