Effects of N deposition on the quality and quantity of soil organic matter in a boreal forest: Contrasting roles of ammonium and nitrate

doi:10.1016/j.catena.2020.104996

	Effects of N deposition on the quality and quantity of soil organic matter in a boreal forest: Contrasting roles of ammonium and nitrate
	Geng, Jing 2; Fang, Huajun 1,3,4,5; Cheng, Shulan 3; Pei, Jie 2
刊名	CATENA
	2021-03-01
卷号	198 页码:9
关键词	Soil organic matter Ammonium fertilization Nitrate fertilization Pyrolysis-gas chromatography/mass spectrometry Boreal forest
ISSN号	0341-8162
DOI	10.1016/j.catena.2020.104996
通讯作者	Fang, Huajun(fanghj@igsnrr.ac.cn)
英文摘要	Elevated nitrogen (N) deposition plays a critical role in soil organic matter (SOM) transformation, but the responses of the quantity and quality of SOM to ammonium and nitrate fertilization remain unclear. In this work, a 6-year field experiment amended with ammonium chloride (NH4Cl) and potassium nitrate (KNO3) fertilizers at four rates of 0, 10, 20, and 40 kg N ha(-1) yr(-1) was conducted in a boreal forest. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) analysis and elemental analysis were used to investigate the chemical composition and soil organic carbon (SOC) contents in bulk soils and two density fractions (light fraction < 1.70 g cm(-3) and heavy fraction > 1.70 g cm(-3)). Soil microbial community composition was determined based on phospholipid fatty acids (PLFAs) analysis. Results showed that the SOC contents in the organic and mineral layers under nitrate addition were significantly increased by 27-87%. By contrast, ammonium addition significantly decreased the SOC contents in the organic layer by 28-54%. Nitrate addition increased relative proportions of acetic acid in the light fraction and toluene in bulk soil, but decreased relative abundance of phenol in bulk soil, indicating that more plant-derived input contributed to the increase of SOC. Contrastingly, ammonium addition increased the proportions of benzene in bulk soil and pyrrole as well as the mineralization index (pyrrole/phenol) in the heavy fraction, suggesting more advanced mineralization degree of SOM. Moreover, ammonium addition altered microbial community structure with a higher ratio of fungi/bacteria (F/B) while nitrate addition had little effect on soil microbial community. Overall, our findings highlight the contrasting roles of ammonium and nitrate in SOM dynamics, which should be distinguished to accurately predict the responses of SOC sequestration to N deposition especially in N-limited boreal forests.
资助项目	National Natural Science Foundation of China[41977041] ; National Natural Science Foundation of China[31770558] ; National Natural Science Foundation of China[41907036] ; Second Tibetan Plateau Scientific Expedition and Research Program (STEP)[2019QZKK1003] ; National Key Research and Development Program of China[2017YFA0604802] ; National Key Research and Development Program of China[2017YFA0604804] ; National Key Research and Development Program of China[2016YFC0500603] ; National Key Research and Development Program of China[2016YFC0503603] ; CAS Strategic Priority Program[XDA200204020] ; CAS Strategic Priority Program[XDA23060401] ; Thousand Talents Plan Project of High-End Innovative Talents of Qinghai Province
WOS关键词	EXTRACELLULAR ENZYME-ACTIVITIES ; PYROLYSIS-GAS CHROMATOGRAPHY ; NITROGEN DEPOSITION ; MICROBIAL COMMUNITY ; CARBON DECOMPOSITION ; MASS-SPECTROMETRY ; FUNGAL ; LITTER ; ADDITIONS ; RESPONSES
WOS研究方向	Geology ; Agriculture ; Water Resources
语种	英语
出版者	ELSEVIER
WOS记录号	WOS:000605337000021
资助机构	National Natural Science Foundation of China ; Second Tibetan Plateau Scientific Expedition and Research Program (STEP) ; National Key Research and Development Program of China ; CAS Strategic Priority Program ; Thousand Talents Plan Project of High-End Innovative Talents of Qinghai Province
内容类型	期刊论文
源URL	[http://ir.igsnrr.ac.cn/handle/311030/136261]
专题	中国科学院地理科学与资源研究所
通讯作者	Fang, Huajun
作者单位	1.Chinese Acad Sci, Key Lab Ecosyst Network Observat & Modeling, Inst Geog Sci & Nat Resources Res, Beijing 100101, Peoples R China 2.Sun Yat Sen Univ, Sch Geospatial Engn & Sci, Zhuhai 519082, Peoples R China 3.Univ Chinese Acad Sci, Coll Resources & Environm, Beijing 100049, Peoples R China 4.Zhongke Jian Inst Ecoenvironm Sci, Jian 343000, Jiangxi, Peoples R China 5.Chinese Acad Sci, Northwest Plateau Inst Biol, Xining 810001, Peoples R China
推荐引用方式 GB/T 7714	Geng, Jing,Fang, Huajun,Cheng, Shulan,et al. Effects of N deposition on the quality and quantity of soil organic matter in a boreal forest: Contrasting roles of ammonium and nitrate[J]. CATENA,2021,198:9.
APA	Geng, Jing,Fang, Huajun,Cheng, Shulan,&Pei, Jie.(2021).Effects of N deposition on the quality and quantity of soil organic matter in a boreal forest: Contrasting roles of ammonium and nitrate.CATENA,198,9.
MLA	Geng, Jing,et al."Effects of N deposition on the quality and quantity of soil organic matter in a boreal forest: Contrasting roles of ammonium and nitrate".CATENA 198(2021):9.