Modelling the effects of climate on long-term patterns of dissolved organic carbon concentrations in the surface waters of a boreal catchment

Abstract. Dissolved organic carbon concentrations ([DOC]) in surface waters are increasing in many regions of Europe and North America. These increases are likely driven by a combination of changing climate, recovery from acidification and change in severity of winter storms in coastal areas. INCA-C, a process-based model of climate effects on surface water [DOC], was used to explore the mechanisms by which changing climate controls seasonal to inter-annual patterns of [DOC] in the lake and outflow stream of a small Finnish catchment between 1990 and 2003. Both production in the catchment and mineralization in the lake controlled [DOC] in the lake. Concentrations in the catchment outflow were controlled by rates of DOC production in the surrounding organic soils. The INCA-C simulation results were compared to those obtained using artificial neural networks (ANN). In general, "black box" ANN models provide better fits to observed data but process-based models can identify the mechanism responsible for the observed pattern. A statistically significant increase was observed in both INCA-C modelled and measured annual average [DOC] in the lake. This suggests that some of the observed increase in surface water [DOC] is caused by climate-related processes operating in the lake and catchment. However, a full understanding of surface water [DOC] dynamics can only come from catchment-scale process-based models linking the effects of changing climate and deposition on aquatic and terrestrial environments.

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Impacts of Droughts and Acidic Deposition on Long-Term Surface Water Dissolved Organic Carbon Concentrations in Upland Catchments in Wales

Frontiers in Environmental Science ◽

10.3389/fenvs.2020.578611 ◽

2020 ◽

Vol 8 ◽

Author(s):

Jaeyoung Lee ◽

Paul G. Whitehead ◽

Martyn N. Futter ◽

Jim W. Hall

Keyword(s):

Surface Water ◽

Organic Carbon ◽

Dissolved Organic Carbon ◽

Acidic Deposition ◽

Carbon Concentrations ◽

Upland Catchments

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THE COMPOSITION OF CYCLOPOID ASSEMBLAGES IN ECOLOGICALLY DIFFERENT GROUNDWATER HABITATS OF A DANUBE RIVERINE WETLAND IN AUSTRIA

Crustaceana ◽

10.1163/156854099503780 ◽

1999 ◽

Vol 72 (8) ◽

pp. 883-892 ◽

Cited By ~ 4

Author(s):

Peter Pospisil

Keyword(s):

Species Richness ◽

Surface Water ◽

Low Temperature ◽

Organic Carbon ◽

Dissolved Organic Carbon ◽

Surface Waters ◽

Groundwater Monitoring ◽

Temperature Fluctuations ◽

Strong Surface ◽

Riverine Wetland

AbstractThe cyclopoid assemblages of three groundwater monitoring sites in the Danube wetlands were investigated from mid 1996 to end 1997. One of these sites, located 200 m from surface waters, represents a stable, oligotrophic habitat (characterized by low temperature fluctuations and low dissolved organic carbon (DOC)-values). Six groundwater cyclopoids permanently inhabit this habitat. At two other sites, located closely to a backwater of the Danube and characterized by strong surface water influences, only four stygobitic cyclopoids occur altogether. These data support modern opinions, which stress that groundwater habitats are more heterogeneous and display higher biodiversity (i. e., higher species richness) of selected crustacean taxocoenoses (in this case, Cyclopoida) than expected earlier. Die Grundwassercyclopiden dreier Untersuchungsstellen in den Donauauen wurden von Juni 1996 bis Dezember 1997 untersucht. Eine dieser Stellen reprasentierte ein stabiles, oligotrophes Habitat (charakterisiert durch geringe Temperaturschwankungen und niedrige ''dissolved organic carbon'' (DOC)-Werte). Dieses Habitat wurde von sechs Grundwassercyclopiden standig besiedelt, im Vergleich zu nur vier Arten an den beiden anderen Stellen zusammen, die durch das nahe Oberflachengewasser stark beeinflusst wurden. Diese Beobachtungen bestatigen die moderne Ansicht, dass im Grundwasser eine grossere Habitatdiversitat sowie eine grossere Biodiversitat (d. h., Artenreichtum) von ausgewahlten Crustaceen-Taxozonosen (in diesem Fall Cyclopoida) zu finden ist als bisher angenommen.

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The role of catchment characteristics in determining surface water nitrogen in four upland regions in the UK

Hydrology and Earth System Sciences ◽

10.5194/hess-11-356-2007 ◽

2007 ◽

Vol 11 (1) ◽

pp. 356-371 ◽

Cited By ~ 44

Author(s):

R. C. Helliwell ◽

M. C. Coull ◽

J. J. L. Davies ◽

C. D. Evans ◽

D. Norris ◽

...

Keyword(s):

Surface Water ◽

Organic Carbon ◽

Dissolved Organic Carbon ◽

Surface Waters ◽

N Deposition ◽

Organic N ◽

Soluble Nitrogen ◽

N Saturation ◽

The South ◽

South Pennines

Abstract. Hydrochemical and catchment data from 80 upland moorland sites in four regions with contrasting climate, soils, geology and geomorphology have been analysed to assess the key catchment attributes that influence enhanced leaching of soluble nitrogen to surface waters. The regions are the South Pennines of northern England, the Snowdonia National Park in north Wales, the Galloway region of south-west Scotland and the Mourne Mountains in Northern Ireland, all highly acidified, with median pH values of <5.5. Linear regression of mean summer and winter concentrations for nitrate (NO3−), ammonium (NH4+), dissolved organic nitrogen (DON) and dissolved organic carbon (DOC) were expressed as functions of catchment attributes. Nitrate concentrations in waters draining catchments dominated by peaty soils (large C pool) were much less than those in catchments dominated by mineral soils (small C pool). Hence, if future N deposition levels are maintained or increase, high-altitude catchments with small carbon pools are potentially more susceptible to NO3− leaching. All N species exhibit seasonality; this is most marked in Galloway and least marked in the South Pennines, which implies that the South Pennines have reached an advanced stage of N saturation. Surface water inorganic N concentrations and the ratio of dissolved organic carbon (DOC) to dissolved organic N (DON) can be related to deposition inputs, although relationships differ throughout the year. If the DOC/DON ratio is indicative of catchment N saturation, levels of N retention are at least partially determined by deposition levels. This study identifies N deposition as a major inter-regional control on the degree of catchment N saturation and on N leaching to surface waters; it stresses the importance of catchment factors in modifying the relationship between N deposition and leaching in acid sensitive UK upland catchments.

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A long-term simulation of the effects of acidic deposition and climate change on surface water dissolved organic carbon concentrations in a boreal catchment

Hydrology Research ◽

10.2166/nh.2009.101 ◽

2009 ◽

Vol 40 (2-3) ◽

pp. 291-305 ◽

Cited By ~ 36

Author(s):

M. N. Futter ◽

M. Forsius ◽

M. Holmberg ◽

M. Starr

Keyword(s):

Climate Change ◽

Surface Water ◽

Organic Carbon ◽

Dissolved Organic Carbon ◽

Monitoring And Evaluation ◽

Doc Concentration ◽

Emissions Scenarios ◽

Carbon Concentrations ◽

Headwater Catchment

Concentrations of dissolved organic carbon (DOC) are increasing in many surface waters across Europe. Two of the main mechanisms proposed to explain this increase are declines in sulfate (SO42−) deposition and changes in climate. Many of the reductions in SO42− have already occurred; climate change related effects are occurring now and will continue in the future. This paper presents the first application of a new version of INCA-C, the Integrated Catchments model for Carbon, which simulates the effects of both climate and SO42− deposition on surface water DOC concentration ([DOC]). The model was applied to Valkea-Kotinen, a small headwater catchment in Finland, where it was able to simulate present-day (1990–2007) trends in [DOC] in the lake and catchment outflow as functions of observed climate and European Monitoring and Evaluation Programme (EMEP)-modelled SO42− deposition. Using a parameter set derived from a present-day calibration, the model was run with two climate scenarios from the Special Report on Emissions Scenarios (SRES) and three EMEP deposition scenarios to simulate surface water [DOC] between 1960 and 2100. The results show that much of the historical increase in [DOC] can be explained as a result of historical declines in SO42− deposition and that surface water [DOC] will continue to increase as climate changes.

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Mercury, monomethyl mercury, and dissolved organic carbon concentrations in surface water entering and exiting constructed wetlands treated with metal-based coagulants, Twitchell Island, California

Data Series ◽

10.3133/ds950 ◽

2015 ◽

Cited By ~ 2

Author(s):

Elizabeth B. Stumpner ◽

Tamara E.C. Kraus ◽

Jacob A. Fleck ◽

Angela M. Hansen ◽

Sandra M. Bachand ◽

...

Keyword(s):

Surface Water ◽

Organic Carbon ◽

Dissolved Organic Carbon ◽

Constructed Wetlands ◽

Monomethyl Mercury ◽

Carbon Concentrations

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BOREAS TGB-05 DISSOLVED ORGANIC CARBON CONCENTRATIONS FROM NSA BEAVER PONDS

ORNL Distributed Active Archive Center Datasets ◽

10.3334/ornldaac/385 ◽

1999 ◽

Author(s):

R. A. BOURBONNIERE

Keyword(s):

Organic Carbon ◽

Dissolved Organic Carbon ◽

Beaver Ponds ◽

Carbon Concentrations

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Groundwater protection and diffuse nitrogen emissions to surface waters – which catchment areas have to be considered?

Water Science & Technology Water Supply ◽

10.2166/ws.2007.072 ◽

2007 ◽

Vol 7 (3) ◽

pp. 103-110

Author(s):

C. Schilling ◽

M. Zessner ◽

A.P. Blaschke ◽

D. Gutknecht ◽

H. Kroiss

Keyword(s):

Surface Water ◽

Total Nitrogen ◽

Surface Waters ◽

Flow Path ◽

Emission Model ◽

Catchment Scale ◽

Danube Basin ◽

Nitrogen Emissions ◽

Nitrogen Levels ◽

Catchment Areas

Two Austrian case study regions within the Danube basin have been selected for detailed investigations of groundwater and surface water quality at the catchment scale. Water balance calculations have been performed using the conceptual continuous time SWAT 2000 model to characterise catchment hydrology and to identify individual runoff components contributing to river discharge. Nitrogen emission calculations have been performed using the empirical emission model MONERIS to relate individual runoff components to specific nitrogen emissions and for the quantification of total nitrogen emissions to surface waters. Calculated total nitrogen emissions to surface waters using the MONERIS model were significantly influenced by hydrological conditions. For both catchments the groundwater could be identified as major emission pathway of nitrogen emissions to the surface waters. Since most of the nitrogen is emitted by groundwater to the surface water, denitrification in groundwater is of considerable importance reducing nitrogen levels in groundwater along the flow path towards the surface water. An approach was adopted for the grid-oriented estimation of diffuse nitrogen emissions based on calculated groundwater residence time distributions. Denitrification in groundwater was considered using a half life time approach. It could be shown that more than 90% of the total diffuse nitrogen emissions were contributed by areas with low groundwater residence times and short distances to the surface water. Thus, managing diffuse nitrogen emissions the location of catchment areas has to be considered as well as hydrological and hydrogeological conditions, which significantly influence denitrification in the groundwater and reduce nitrogen levels in groundwater on the flow path towards the surface water.

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