OPENAIRE OpenAire Sygma Bielefeld Academic Search Engine (BASE) UnpayWall HAL-INSU Recolector de Ciencia Abierta, RECOLECTA Multidisciplinary Digital Publishing Institute Crossref Microsoft Academic Graph HAL-CEA European Union Open Data Portal http://www.mdpi.com/2073-4441/12/6/1722/pdf https://www.mdpi.com/2073-4441/12/6/1722/pdf https://doi.org/10.3390/w12061722 Water Open Access 2020-06-18 2020-10-20 <?xml version='1.0' encoding='UTF-8'?><article><p>Studies exploring how different sources of dissolved organic matter (DOM) influence in-stream dissolved organic carbon (DOC) uptake at the ecosystem scale are scarce in the literature. To fill this knowledge gap, we examined the relationship between DOM sources and in-stream net DOC uptake (UDOC) in a sub-humid Mediterranean stream. We considered four reach-scale scenarios occurring under natural conditions that differed in predominant DOM sources (groundwater, leaf litter, and/or upstream water). Results showed that groundwater inputs favored in-stream net DOC uptake, while leaf litter inputs promoted in-stream net DOC release. However, there was no clear effect of DOM source mixing on the magnitude of UDOC. Further, the variability in UDOC within and among scenarios was mostly explained by stream DOC concentration, suggesting that DOC availability limits microbial activity in this stream. DOM composition became a controlling factor of UDOC variability only during the leaf litter period, when stream DOC concentration was the highest. Together, these results suggest that the capacity of headwater forested streams to process DOC is closely tied to the availability of different DOM sources and how they vary over time and along the river network.</p></article> [SDU.OCEAN]Sciences of the Universe [physics]/Ocean leaf litter carbon availability Atmosphere [SDU.OCEAN] Sciences of the Universe [physics]/Ocean, Atmosphere 577 Leaf litter 910 15. Life on land dissolved organic carbon 01 natural sciences [SDU.ENVI] Sciences of the Universe [physics]/Continental interfaces, environment 6. Clean water Dissolved organic matter composition groundwater inputs 13. Climate action Groundwater inputs dissolved organic matter composition In-stream net uptake [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces Dissolved organic carbon environment in-stream net uptake Carbon availability 0105 earth and related environmental sciences Anna Lupon, Núria Catalán, Eugènia Martí, Susana Bernal, 2020-06-17 journalpaper <?xml version='1.0' encoding='UTF-8'?><article><p>Studies exploring how different sources of dissolved organic matter (DOM) influence in-stream dissolved organic carbon (DOC) uptake at the ecosystem scale are scarce in the literature. To fill this knowledge gap, we examined the relationship between DOM sources and in-stream net DOC uptake (UDOC) in a sub-humid Mediterranean stream. We considered four reach-scale scenarios occurring under natural conditions that differed in predominant DOM sources (groundwater, leaf litter, and/or upstream water). Results showed that groundwater inputs favored in-stream net DOC uptake, while leaf litter inputs promoted in-stream net DOC release. However, there was no clear effect of DOM source mixing on the magnitude of UDOC. Further, the variability in UDOC within and among scenarios was mostly explained by stream DOC concentration, suggesting that DOC availability limits microbial activity in this stream. DOM composition became a controlling factor of UDOC variability only during the leaf litter period, when stream DOC concentration was the highest. Together, these results suggest that the capacity of headwater forested streams to process DOC is closely tied to the availability of different DOM sources and how they vary over time and along the river network.</p></article> Influence of Dissolved Organic Matter Sources on In-Stream Net Dissolved Organic Carbon Uptake in a Mediterranean Stream 10.3390/w12061722 839709