caa a22 4500 605517002 CHVBK 20210128100717.0 cr unu---uuuuu 210128e20150401xx s 000 0 eng 10.1007/s10533-015-0071-x doi (NATIONALLICENCE)springer-10.1007/s10533-015-0071-x Spatial controls on dissolved organic carbon in upland waters inferred from a simple statistical model [Elektronische Daten] [Donald Monteith, Peter Henrys, Chris Evans, Iain Malcolm, Ewan Shilland, M. Pereira] Dissolved organic carbon (DOC) concentrations in upland surface waters in many northern hemisphere industrialised regions are at their highest in living memory, provoking debate over their "naturalness”. Because of the implications for drinking water treatment and supply there is increasing interest in the potential for mitigation through local land management, and for forecasting the likely impact of environmental change. However, the dominant controls on DOC production remain unresolved, hindering the establishment of appropriate reference levels for specific locations. Here we demonstrate that spatial variation in long-term average DOC levels draining upland UK catchments is highly predictable using a simple multiple logistic regression model comprising variables representing wetland soil cover, rainfall, altitude, catchment sensitivity to acidification and current acid deposition. A negative relationship was observed between DOC concentration and altitudethat, for catchments dominated by organo-mineral soils, is plausibly explained by the combined effects of changing net primary production and temperature-dependent decomposition. However, the magnitude of the altitude effect was considerably greater for catchments with a high proportion of wetland cover, suggesting that additional controls influence these sites such as impeded respiratory loss of carbon in wet soils and/or an increased susceptibility to water level drawdown at lower altitudes. The model suggests (1) that continuing reductions in sulphur deposition on acid sensitive organo-mineral soils, will drive further significant increases in DOC and, (2) given the differences in the magnitude of the observed altitude-DOC relationships, that DOC production from catchments with peat-dominated soils may be more sensitive to climate change than those dominated by mineral soils. However, given that mechanisms remain unclear, the latter warrants further investigation. Springer International Publishing Switzerland, 2015 Dissolved organic carbon nationallicence Dissolved organic matter nationallicence Upland waters nationallicence Acidification nationallicence Recovery nationallicence Climate change nationallicence Land use nationallicence Monteith Donald NERC Centre for Ecology & Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, LA1 4AP, Lancaster, UK aut Henrys Peter NERC Centre for Ecology & Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, LA1 4AP, Lancaster, UK aut Evans Chris NERC Centre for Ecology & Hydrology, Environment Centre Wales, Deiniol Road, LL57 2UW, Bangor, UK aut Malcolm Iain Marine Scotland Freshwater Laboratory, Faskally, PH16 5LB, Pitlochry, Perthshire, Scotland, UK aut Shilland Ewan Environmental Change Research Centre, University College London, Gower Street, WC1E 6BT, London, UK aut Pereira M. NERC Centre for Ecology & Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, LA1 4AP, Lancaster, UK aut Biogeochemistry Springer International Publishing 123/3(2015-04-01), 363-377 0168-2563 123:3<363 2015 123 10533 https://doi.org/10.1007/s10533-015-0071-x text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10533-015-0071-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Monteith Donald NERC Centre for Ecology & Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, LA1 4AP, Lancaster, UK aut NATIONALLICENCE 700 1- Henrys Peter NERC Centre for Ecology & Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, LA1 4AP, Lancaster, UK aut NATIONALLICENCE 700 1- Evans Chris NERC Centre for Ecology & Hydrology, Environment Centre Wales, Deiniol Road, LL57 2UW, Bangor, UK aut NATIONALLICENCE 700 1- Malcolm Iain Marine Scotland Freshwater Laboratory, Faskally, PH16 5LB, Pitlochry, Perthshire, Scotland, UK aut NATIONALLICENCE 700 1- Shilland Ewan Environmental Change Research Centre, University College London, Gower Street, WC1E 6BT, London, UK aut NATIONALLICENCE 700 1- Pereira M. NERC Centre for Ecology & Hydrology, Lancaster Environment Centre, Library Avenue, Bailrigg, LA1 4AP, Lancaster, UK aut NATIONALLICENCE 773 0- Biogeochemistry Springer International Publishing 123/3(2015-04-01), 363-377 0168-2563 123:3<363 2015 123 10533