干旱区生态环境知识资源中心(Arid): Source contributions in precipitation chemistry and analysis of atmospheric nitrogen deposition in a Sahelian dry savanna site in West Africa

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DOI	10.1016/j.atmosres.2020.105423
	Source contributions in precipitation chemistry and analysis of atmospheric nitrogen deposition in a Sahelian dry savanna site in West Africa
	Laouali, D.; Delon, C.; Adon, M.; Ndiaye, O.; Saneh, I; Gardrat, E.; Dias-Alves, M.; Tagesson, T.; Fensohlt, R.; Galy-Lacaux, C.
通讯作者	Galy-Lacaux, C (corresponding author), Univ Toulouse, Lab Aerol, Toulouse, France.
来源期刊	ATMOSPHERIC RESEARCH
ISSN	0169-8095
EISSN	1873-2895
出版年	2021
卷号	251
英文摘要	Experimental data on precipitation chemistry were collected at a semi-arid savanna in Senegal (Dahra) in 2013, 2014 and 2017. The chemical composition of precipitation was analyzed for inorganic and organic ions, using ionic chromatography. The pH values of precipitation range from 4.50 to 8.50 with 89% of the samples having basic pH. The composition of precipitation was controlled by four source contributions: marine, terrigenous, biogenic, and organic acids emissions from vegetation. The terrigenous contribution was the highest accounting for 42% of the total annual Volume Weighted Mean ionic concentrations, due to the proximity of the Saharan desert, followed by the marine source representing 36%, due to the location of Dahra close to the Atlantic Ocean. Nitrogenous (N) contribution represents 16% of the mean annual total ionic charge, from biogenic sources and livestock crossing the site all year round. Finally, the lowest contribution is from organic acidity (5%), due to the low density of vegetation especially during the dry season. Wet deposition fluxes in Dahra for all compounds show larger values than at other Sahelian savanna sites. Dry N deposition in Dahra was also estimated by inferential method using gas concentration measurements and modeled dry deposition velocities. The total N deposition fluxes (wet plus dry) range from 3.80 to 4.81 kgN ha(-1) yr(-1), comparable to fluxes at other semi-arid savannas in Niger and Mali. Wet deposition contributed with 37-53% of the total N flux, suggesting that wet N deposition is equally important to dry deposition fluxes for direct N loading to savanna ecosystems in the Sahel, with a large contribution of reduced compounds. This study shows that Dahra presents a precipitation chemistry composition with characteristics close to those from other Sahelian sites, with however the specificity of being more influenced by the proximity of the Atlantic ocean and the presence of livestock year round.
英文关键词	Precipitation chemistry Semi-arid climate West Africa Wet deposition Dry deposition Nitrogen
类型	Article
语种	英语
开放获取类型	hybrid, Green Published
收录类别	SCI-E
WOS记录号	WOS:000612175100001
WOS关键词	WET DEPOSITION ; CHEMICAL-COMPOSITION ; RAINWATER CHEMISTRY ; GRAZED ECOSYSTEM ; SULFUR-DIOXIDE ; SEA-SALT ; EMISSIONS ; SOIL ; FLUXES ; MODEL
WOS类目	Meteorology & Atmospheric Sciences
WOS研究方向	Meteorology & Atmospheric Sciences
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/349660
作者单位	[Laouali, D.] Univ Abdou Mournouni, Fac Sci & Tech, BP 10662, Niamey, Niger; [Delon, C.; Gardrat, E.; Dias-Alves, M.; Galy-Lacaux, C.] Univ Toulouse, Lab Aerol, Toulouse, France; [Adon, M.] Univ Felix Houphouet Boigny, Lab Phys Atmosphere, Abidjan, Cote Ivoire; [Ndiaye, O.; Saneh, I] Inst Senegalais Rech Agr, Ctr Rech Zootech Dahra, Dahra, Senegal; [Tagesson, T.; Fensohlt, R.] Univ Copenhagen, Dept Geosci & Nat Resource Management, Copenhagen, Denmark; [Tagesson, T.] Lund Univ, Dept Phys Geog & Ecosyst Sci, Lund, Sweden; [Adon, M.] Univ Jean Lorougnon Guede, Lab Sci & Tech Environm, Daloa, Cote Ivoire
推荐引用方式 GB/T 7714	Laouali, D.,Delon, C.,Adon, M.,et al. Source contributions in precipitation chemistry and analysis of atmospheric nitrogen deposition in a Sahelian dry savanna site in West Africa[J],2021,251.
APA	Laouali, D..,Delon, C..,Adon, M..,Ndiaye, O..,Saneh, I.,...&Galy-Lacaux, C..(2021).Source contributions in precipitation chemistry and analysis of atmospheric nitrogen deposition in a Sahelian dry savanna site in West Africa.ATMOSPHERIC RESEARCH,251.
MLA	Laouali, D.,et al."Source contributions in precipitation chemistry and analysis of atmospheric nitrogen deposition in a Sahelian dry savanna site in West Africa".ATMOSPHERIC RESEARCH 251(2021).