不同耕作模式下稻田生态系统对田面水中无机态氮的消纳  

Inorganic Nitrogen Sequestration in Rice-based Ecosystems by Different Times of Fertilization and Tillage Methods

作　　者：唐颖[1] 黄慰情[1] 黄耀华[1] 雷琳[1] 黄登海[1] 蒋先军[1] 周鑫斌[1] 谢德体[1] 

机构地区：[1]西南大学资源环境学院,重庆400715

出　　处：《西南师范大学学报（自然科学版）》2011年第6期62-68,共7页Journal of Southwest China Normal University(Natural Science Edition)

基　　金：国家科技支撑计划"沿三峡水库(重大工程区)农业面源污染防控与综合治理技术研究"(2007BAD87B10)

摘　　要：稻田生态系统可以有效减少流入水体的农业面源污染物.本文通过模拟试验,研究了不同施肥时间(常规施肥时间和在此基础上提前一个半月施肥)以及在不同耕作模式(垄作、平作)下稻田生态系统对田面水中无机态氮的消纳效果.结果表明:稻田生态系统能够有效降低田面水中无机态氮、全磷的含量.与灌水第1d相比,灌水14d后,所有稻田田面水中NH4+-N浓度平均下降84.3%,灌水21d后,所有稻田田面水中NO3--N浓度平均下降64.6%,TP浓度下降58.0%;提前施肥条件下稻田生态系统对田面水中无机态氮具有更好的吸附、消纳效果,灌水后的第1d,所有稻田田面水中NH4+-N浓度均出现最高值,其中,常规时间施肥和提前施肥NH4+-N质量体积浓度分别为2.52和1.28mg/L,灌水后的第3d,常规时间施肥稻田田面水中NO3--N质量体积浓度上升至最大值5.92mg/L,而此时提前施肥稻田约为3.65mg/L;不同耕作模式对无机态氮消纳的影响差异不显著.Rice-based ecosystems could be used to sequestrate pollutants from agricultural waste water. Through the simulation test, the consumption of inorganic nitrogen was studied in the paddy field surface water under different fertilization time（regular fertilization time and fertilized one and a half month earlier, which was called early irrigation in the present paper）and different tillage methods （ridge tillage and con ventional tillage）. It was found that： rice-based ecosystem could effectively reduce the contents of inorgan- ic nitrogen and total phosphorus in paddy field surface water. Compared with the first day, the concentra- tion of NH4＋ --N in paddy field surface water had reduced by 84.3% after 14 days of irrigation,the concen- tration of NO/--N decreased by 64.6% after 21 days of irrigation and total phosphorus reduced by 58.0% at the same time; rice-based ecosystems had a better adsorption in inorganic nitrogen when early fertiliza- tion, the concentration of NH＋ --N in paddy field surface water were all reached their peak values 1 day af- ter irrigation, with 2.52mg/L in regular fertilization and 1.28mg/L in early fertilization, but the concen tration of NO3---N in regular fertilization reached the peak value of 5.92 mg/L about 3 days after irriga- tion, and 3.65 mg/L in early fertilization at the same time; there was no obvious difference about adsorp- tion in inorganic nitrogen between ridge tillage and conventional tillage.

关 键 词：面源污染 稻田生态系统 保护性耕作 

分 类 号：X592[环境科学与工程—环境工程]