DOI: 10.1007/s10533-014-9984-z
Scopus记录号: 2-s2.0-84904797216
论文题名: Patterns and drivers of riverine nitrogen (N) across alpine, subarctic, and boreal Sweden
作者: Sponseller R.A. ; Temnerud J. ; Bishop K. ; Laudon H.
刊名: Biogeochemistry
ISSN: 0168-2563
EISSN: 1573-515X
出版年: 2014
卷: 120, 期: 2018-01-03 起始页码: 105
结束页码: 120
语种: 英语
英文关键词: Catchment
; Inorganic nitrogen
; Organic nitrogen
; Rivers
; Streams
; Watershed
英文摘要: Concentrations of nitrogen (N) in surface waters reflect the export of different organic and inorganic forms from terrestrial environments and the modification of these resources within aquatic habitats. We evaluated the relative influence of terrestrial ecosystem state factors, anthropogenic gradients, and aquatic habitat variables on patterns of N concentration in streams and rivers across Sweden. We analyzed data from 115 national monitoring stations distributed along a 1,300 km latitudinal gradient, draining catchments that differed by more than 10 °C in mean annual temperature (MAT), and more than five orders of magnitude in area. Regional trends in total organic nitrogen (TON) and carbon:nitrogen (C:N) were closely linked to broad-scale gradients in state factors (e.g., MAT), reflecting the importance of long-term ecosystem development on terrestrial organic matter accrual and export. In contrast, trends in nitrate (NO3 -), the dominant form of inorganic N, were largely unrelated to state factors, but instead were closely connected to gradients related to anthropogenic inputs (e.g., agricultural cover). Despite large differences in drainage size and cover by lakes and wetlands among sites, these descriptors of the aquatic environment had little influence on spatial patterns of N chemistry. The temporal variability in N concentrations also differed between forms: inorganic N was strongly seasonal, with peaks during dormant periods that underscore biotic control over terrestrial losses of limiting resources. Organic N showed comparatively weaker seasonality, but summertime increases suggest temperature-driven patterns of soil TON production and export-temporal signals which were modified by variables that govern water residence time within catchments. Unique combinations of regional predictors reflect basic differences in the cycling of organic versus inorganic N and highlight variation in the sensitivity of these different N forms to environmental changes that directly alter inputs of resources, or indirectly modify terrestrial ecosystems through shifts in species composition, rates of forest productivity, soil development, and hydrologic routing. © 2014 Springer International Publishing Switzerland. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/83721
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: Department of Ecology and Environmental Science, Umeå University, Umeå, Sweden; Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden; Swedish Meteorological and Hydrological Institute (SMHI), Norrköping, Sweden; Department of Earth Sciences, Uppsala University, Uppsala, Sweden; Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
Recommended Citation:
Sponseller R.A.,Temnerud J.,Bishop K.,et al. Patterns and drivers of riverine nitrogen (N) across alpine, subarctic, and boreal Sweden[J]. Biogeochemistry,2014-01-01,120(2018-01-03)