DOI: 10.1007/s10533-013-9909-2
Scopus记录号: 2-s2.0-84896351767
论文题名: Influence of emergent vegetation on nitrate cycling in sediments of a groundwater-fed river
作者: Ullah S. ; Zhang H. ; Heathwaite A.L. ; Heppell C. ; Lansdown K. ; Binley A. ; Trimmer M.
刊名: Biogeochemistry
ISSN: 0168-2563
EISSN: 1573-515X
出版年: 2014
卷: 118, 期: 2018-01-03 起始页码: 121
结束页码: 134
语种: 英语
英文关键词: Emergent vegetation
; Groundwater-fed rivers
; Nitrate cycling
; Riverbed sediments
; Water quality
Scopus关键词: anoxic conditions
; concentration (composition)
; denitrification
; dissolved organic carbon
; dissolved oxygen
; emergence
; fluvial deposit
; immobilization
; nitrate
; nutrient cycling
; piezometer
; river bed
; sediment analysis
; sediment chemistry
; vegetation structure
; Cumbria
; England
; Leith River
; United Kingdom
英文摘要: Emergent vegetation in river beds can play a significant role in nutrient cycling in riverine sediments. We analysed and compared pore water NO3 - concentration gradients in the sediments of the River Leith, Cumbria, UK, in the presence and absence of emergent vegetation (dominated by Sparganium spp.). High resolution (1 cm interval), in situ, vertical profiles of NO3 - to 30 cm depth were measured using deployment of diffusive equilibrium in thin films probes on four occasions from July to September 2010. We found significantly (p < 0.05) lower NO3 - concentration under vegetated sediments (VS) compared to those under adjacent un-vegetated sediments (UVS). Concentrations of dissolved oxygen, measured in pore water collected from multi-level piezometers at 10, 20, 25, 30 and 35 cm depths at the VS and UVS sties, were generally lower under VS (median concentration = 28 μM) than under UVS (median = 132 μM) and correlated significantly with NO3 - concentration (Spearman's r = 0.74, p < 0.05). Similarly, pore water dissolved organic carbon (DOC) concentration was 2.8 times higher under VS compared to UVS, and correlated negatively with NO3 - concentration (Spearman's r = -0.39, p < 0.05). Specific ultra-violet absorption at 254 nm (SUVA) and per cent aromaticity values of DOC were significantly higher under VS (p < 0.05), suggesting that the DOC contained more complex (aromatic) compounds than DOC recorded under UVS. We suggest that, the higher quantity of DOC and its distinct SUVA and percentage aromaticity under VS may have supported faster dissolved oxygen consumption, with the creation of anoxic zones conducive for NO3 - reduction mainly through denitrification. Metabolic uptake and immobilization of NO3 - by plants and microbes may have further contributed to lower NO3 - concentrations under VS. As Sparganium spp. is a common plant growing in river beds in the UK, its role in NO3 - cycling should be considered in attempts to accurately budget N cycling in river beds. © 2013 Springer Science+Business Media Dordrecht. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/83631
Appears in Collections: 气候减缓与适应 气候变化事实与影响
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作者单位: Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, United Kingdom; School of Physical and Geographical Sciences, Keele University, Staffordshire, ST5 5BG, United Kingdom; School of Geography, Queen Mary University of London, Mile End Rd, London, E1 4NS, United Kingdom; School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Rd, London, E1 4NS, United Kingdom
Recommended Citation:
Ullah S.,Zhang H.,Heathwaite A.L.,et al. Influence of emergent vegetation on nitrate cycling in sediments of a groundwater-fed river[J]. Biogeochemistry,2014-01-01,118(2018-01-03)