干旱区生态环境知识资源中心(Arid): Nitrogen cycling and environmental impacts in upland agricultural soils in North China: A review

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	Nitrogen cycling and environmental impacts in upland agricultural soils in North China: A review
	Ju Xiaotang; Zhang Chong
来源期刊	Journal of Integrative Agriculture
ISSN	2095-3119
出版年	2017
卷号	16 期号:12 页码:2848-2862
英文摘要	The upland agricultural soils in North China are distributed north of a line between the Kunlun Mountains, the Qinling Mountains and the Huaihe River. They occur in arid, semi-arid and semi-humid regions and crop production often depends on rain-fed or irrigation to supplement rainfall. This paper summarizes the characteristics of gross nitrogen (N) transformation, the fate of N fertilizer and soil N as well as the N loss pathway, and makes suggestions for proper N management in the region. The soils of the region are characterized by strong N mineralization and nitrification, and weak immobilization and denitrification ability, which lead to the production and accumulation of nitrate in the soil profile. Large amounts of accumulated nitrate have been observed in the vadose-zone in soils due to excess N fertilization in the past three decades, and this nitrate is subject to occasional leaching which leads to groundwater nitrate contamination. Under farmer's conventional high N fertilization practice in the winter wheat-summer maize rotation system (N application rate was approximately 600 kg ha~(-1) yr~(-1)), crop N uptake, soil residual N, NH_3 volatilization, NO_3~- leaching, and denitrification loss accounted for around 27, 30, 23, 18 and 2% of the applied fertilizer N, respectively. NH_3 volatilization and NO_3~- leaching were the most important N loss pathways while soil residual N was an important fate of N fertilizer for replenishing soil N depletion from crop production. The upland agricultural soils in North China are a large source of N_2O and total emissions in this region make up a large proportion (approximately 54%) of Chinese cropland N_2O emissions. The non-coupled strong ammonia oxidation process is an important mechanism of N_2O production. Slowing down ammonia oxidation after ammonium-N fertilizer or urea application and avoiding transient high soil NH_4~+ concentrations are key measures for reducing N_2O emissions in this region. Further N management should aim to minimize N losses from crop and livestock production, and increase the recycling of manure and straw back to cropland. We also recommend adoption of the 4R (Right soure, Right rate, Right time, Right place) fertilization techniques to realize proper N fertilizer management, and improving application methods or modifying fertilizer types to reduce NH_3 volatilization, improving water management to reduce NO_3~- leaching, and controlling the strong ammonia oxidation process to abate N_2O emission. Future research should focus on the study of the trade-off effects among different N loss pathways under different N application methods or fertilizer products.
英文关键词	N transformation NH_3 volatilization ammonia oxidation NO_3~- leaching N_2O emission upland agricultural soils
类型	Article
语种	英语
收录类别	CSCD
WOS研究方向	Agriculture
CSCD记录号	CSCD:6136719
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/335884
作者单位	Ju Xiaotang, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.; Zhang Chong, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China.
推荐引用方式 GB/T 7714	Ju Xiaotang,Zhang Chong. Nitrogen cycling and environmental impacts in upland agricultural soils in North China: A review[J],2017,16(12):2848-2862.
APA	Ju Xiaotang,&Zhang Chong.(2017).Nitrogen cycling and environmental impacts in upland agricultural soils in North China: A review.Journal of Integrative Agriculture,16(12),2848-2862.
MLA	Ju Xiaotang,et al."Nitrogen cycling and environmental impacts in upland agricultural soils in North China: A review".Journal of Integrative Agriculture 16.12(2017):2848-2862.