Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1029/2020JG006104
Licence creative commons licence
Title (Primary) Temporal patterns of methane emissions from two streams with different riparian connectivity
Author Leng, P. ORCID logo ; Kamjunke, N.; Li, F.; Koschorreck, M.
Journal Journal of Geophysical Research-Biogeosciences
Year 2021
Department SEEFO; FLOEK
Volume 126
Issue 8
Page From e2020JG006104
Language englisch
Topic T4 Coastal System
Keywords streams; methane (CH4); emissions; temporal variability; long-term monitoring; hydrologic connectivity
Abstract Streams are regionally important sources of CH4 to the atmosphere, but the temporal variability in and control on CH4 concentrations and emissions are not well understood. Especially, lack of long-term data hampers our ability to predict CH4 emissions from streams. Here, we present a seven-year data set of biweekly CH4 concentration and underlying potential drivers from two adjacent small German streams with contrasting riparian area characteristics. Over the seven-year study period, mean CH4 concentration and emissionswere 0.20 and 0.07 μmol L–1 and 2.01 and 0.84 mmol m–2 d–1 for the two streams, respectively. Our findings suggest that the combination of seasonality and topography ultimately shaped the considerable temporal variations of CH4. CH4 oxidation and production in the streams were probably of minor importance. Instead, fluctuations in CH4 concentrations likely reflected temporal pattern of CH4 input from soils of the riparian zone with larger CH4 variations in the stream with more riparian lands. Structural equation modeling revealed DOC and nitrate as important predictors of CH4 concentration. However, we did not identify predictors of the considerable short-term variability, nor the explicit pathways of CH4 delivery to streams. The discrepancy of the CH4 flux between streams was likely triggered by different connectivity to riparian soils with higher CH4 emissions in the hydrologically more connected stream. Inter-annual comparison showed that changing hydrologic conditions, rather than warming, may impact future CH4 emissions from temperate streams. We predict higher CH4 emissions occur in wetter years in streams with close connectivity to riparian soils.
Persistent UFZ Identifier
Leng, P., Kamjunke, N., Li, F., Koschorreck, M. (2021):
Temporal patterns of methane emissions from two streams with different riparian connectivity
J. Geophys. Res.-Biogeosci. 126 (8), e2020JG006104