摘要
稻田氮素径流损失是农业面源污染主要来源之一,以巢湖地区单季稻田为研究对象,利用该地区1957—2019年的历史气象数据,通过设定插秧区间(6月6—25日)及施肥期水位(3,10,20 cm),建立SMNRL模型,模拟不同插秧时间和田面水水位稻田氮素流失,研究降低长江中下游平原气候区单季稻田氮素径流损失风险的插秧时间与水位控制模式。结果表明:(1)施肥后,稻田田面水氮素浓度呈指数衰减,基肥期田面水氮素衰减期为9天,分蘖肥和穗肥期为7天。(2)在LW、HW组合中,各施肥期占全生育的氮素径流损失为基肥期>分蘖肥期>穗肥期。在LW组合中,基肥期为氮素径流损失高发期,基肥、分蘖肥、穗肥的氮素流失为72.4%~98.4%,1.9%~27.6%,0~8.3%。(3)控制水位比选择插秧时间对降低氮素径流损失更有效。相同水位下,适宜的插秧期氮素径流损失在全生育期施肥中合计能减少0.4~4.5 kg/hm^2,降低32.8%~80.3%;相同插秧时间下,LW、MW组合相比HW组合氮素径流损失能减少8.8~13.1 kg/hm^2,降低92.1%~98.8%。(4)在LW、MW、HW 3种组合中,插秧期分别以6月19日、6月11日、6月17日为界,将6月6—25日分为前后2个阶段,前1阶段插秧产生氮素径流损失均值显著低于后1阶段,分别低37.0%,25.0%,21.7%。(5)降低巢湖地区稻田氮素径流损失有效措施为施肥期水位控制为3 cm,并选择6月6-19日期间进行水稻插秧。
Nitrogen runoff loss from paddy fields is one of the main sources of agricultural non-point source pollution.In order to reduce the risk of nitrogen runoff loss from single-crop paddy fields in the climatic zone of the middle and lower reaches of the Yangtze River,a suitable fertilization and water level control model for this region was sought and the model of the SMNRL was built.This article used the historical meteorological data from 1957 to 2019 in the Chaohu Lake area by setting the rice transplanting interval(June 6 to 25)and the water level(3,10,20 cm)to simulate nitrogen loss in paddy fields.The result showed that:(1)After fertilization,the nitrogen concentration in the paddy field surface decreased exponentially.Nitrogen decay time of field water was 9 days at base fertilizer stage,and 7 days at tillering and earing fertilizer stage.(2)According to the order of nitrogen runoff loss that accounts for the whole growth in each fertilization period,in the combination of LW and HW,it was the basal fertilizer stage,the tiller fertilizer stage,and the panicle fertilizer stage.The nitrogen loss of basal fertilizer,tiller fertilizer,and panicle fertilizer was respectively 72.4%to 98.4%,1.9%to 27.6%,and 0 to 8.3%in the combination of LW,and the basal fertilizer period was the period of high nitrogen runoff loss.(3)Controlling water level was more effective than reducing planting time to reduce nitrogen runoff loss.Under the same water level,the total nitrogen runoff loss during the transplanting period were reduced by 0.4 to 4.5 kg/hm^2 and 32.8%to 80.3%during the whole growth period.Under the same transplanting time,the nitrogen runoff loss of the LW and MW combinations were reduced by 8.8 to 13.1 kg/hm^2 and 92.1%to 98.8%compared with the HW combination.(4)In the three combinations of LW,MW,and HW,June 6 to 25 was divided into the early and late stages of rice transplanting,with June 19,June 11,and June 17 as the boundaries respectively.The average nitrogen runoff loss in the early stage could be reduced by 37.
作者
文想成
张泰
董世杰
姚瑶
程钶强
李祥
王凤文
程志庆
马友华
杨书运
WEN Xiangcheng;ZHANG Tai;DONG Shijie;YAO Yao;CHENG Keqiang;LI Xiang;WANG Fengwen;CHENG Zhiqing;MA Youhua;YANG Shuyun(School of Resources and Environment, Anhui Agricultural University, Hefei 230036;Meteorological Bureau of Luan City, Anhui Province, Luan, Anhui 237000)
出处
《水土保持学报》
CSCD
北大核心
2021年第1期24-35,共12页
Journal of Soil and Water Conservation
基金
国家重点研发计划项目(2017YFD0301301)。
关键词
长江中下游平原
巢湖地区
单季稻
氮素流失损失
流失风险
plain of the middle and lower reaches of the Yangtze River
Chaohu area
single cropping rice
nitrogen runoff loss
loss risk
