Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

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Quantification and attribution of urban fossil fuel emissions through atmospheric measurements
Super, Ingrid - \ 2018
Wageningen University. Promotor(en): Wouter Peters, co-promotor(en): Michiel van der Molen; H.A.C. Denier van der Gon. - Wageningen : Wageningen University - ISBN 9789463434980 - 192
A multi-model approach to monitor emissions of CO2 and CO from an urban–industrial complex
Super, I. ; Denier van der Gon, H.A.C. ; Molen, M.K. van der; Sterk, H.A.M. ; Hensen, A. ; Peters, W. - \ 2017
Atmospheric Chemistry and Physics 17 (2017). - ISSN 1680-7316 - p. 13297 - 13316.
Monitoring urban–industrial emissions is often challenging because observations are scarce and regional atmospheric transport models are too coarse to represent the high spatiotemporal variability in the resulting concentrations.
In this paper we apply a new combination of an Eulerian model (Weather Research and Forecast, WRF, with chemistry) and a Gaussian plume model (Operational Priority Substances – OPS). The modelled mixing ratios are compared to observed CO2 and CO mole fractions at four sites along a transect from an urban–industrial complex (Rotterdam, the Netherlands) towards rural conditions for
October–December 2014. Urban plumes are well-mixed at our semi-urban location, making this location suited for an integrated emission estimate over the whole study area. The signals at our urban measurement site (with average enhancements of 11 ppm CO2 and 40 ppb CO over the baseline) are highly variable due to the presence of distinct source areas dominated by road traffic/residential heating emissions or industrial activities. This causes different emission signatures that are translated into a large variability in observed
1COV1CO2 ratios, which can be used to identify dominant source types. We find that WRF-Chem is able to represent synoptic variability in CO2 and CO (e.g. the median CO2 mixing ratio is 9.7 ppm, observed, against 8.8 ppm, modelled),
but it fails to reproduce the hourly variability of daytime urban plumes at the urban site (R2 up to 0.05). For the urban site, adding a plume model to the model framework is beneficial to adequately represent plume transport especially
from stack emissions. The explained variance in hourly, daytime CO2 enhancements from point source emissions increases from 30% with WRF-Chem to 52% with WRFChem in combination with the most detailed OPS simulation.
The simulated variability in 1COV1CO2 ratios decreases drastically from 1.5 to 0.6 ppbppm􀀀1, which agrees better with the observed standard deviation of 0.4 ppbppm􀀀1. This is partly due to improved wind fields (increase in R2 of 0.10) but also due to improved point source representation (increase in R2 of 0.05) and dilution (increase in R2 of 0.07). Based on our analysis we conclude that a plume model with detailed and accurate dispersion parameters adds substantially to top–down monitoring of greenhouse gas emissions in urban environments with large point source contributions within a 10 km radius from the observation sites.
Interpreting continuous in-situ observations of carbon dioxide and carbon monoxide in the urban port area of Rotterdam
Super, I. ; Denier van der Gon, H.A.C. ; Visschedijk, A.J.H. ; Moerman, M.M. ; Chen, H. ; Molen, M.K. van der; Peters, W. - \ 2017
Atmospheric Pollution Research 8 (2017)1. - ISSN 1309-1042 - p. 174 - 187.
CO:CO ratio - Concentration gradient - Urban CO flux - Urban monitoring

Large networks of expensive instruments are often used to independently quantify and monitor urban CO2 emissions with sufficient level of detail. However, many developing regions cannot afford such a monitoring effort. We explore the use of a simple, less costly method to constrain urban emissions using only two measurement sites, one upwind and one downwind of the city of Rotterdam in the Netherlands. This provides an interesting dataset of concentration gradients of multiple combustion tracers over an urban-industrial complex. We find clear emission signals from three source sectors, mainly related to industrial activities in the port and from residential areas. We estimate the anthropogenic CO2 emissions for three footprints from our observations and find them in reasonable agreement with the Dutch National Emission Registration (NER) database after accounting for biogenic fluxes. The large confidence interval for one of the footprints illustrates that the presence of point sources complicates the flux estimates. Additionally, we were able to pinpoint a limitation in the emission database using observed fossil fuel CO:CO2 ratios, although the applicability of this method is limited for the footprint with a large influence from point source emissions. There is also a large variability in the observed ratios per footprint, which indicates that the dominant source type varies over time. Finally, we show that the fossil fuel CO concentration can be used to calculate fossil fuel CO2 if their emission ratio is well-known.

Impact of a future H2 transportation on atmospheric pollution in Europe
Popa, M.E. ; Segers, A.J. ; Denier van der Gon, H.A.C. ; Krol, M.C. ; Visschedijk, A.J.H. ; Schaap, M. ; Röckmann, T. - \ 2015
Atmospheric Environment 113 (2015). - ISSN 1352-2310 - p. 208 - 222.
Air quality - Europe - Hydrogen vehicles - Road traffic

Hydrogen (H2) is being explored as a fuel for passenger vehicles; it can be used in fuel cells to power electric motors or burned in internal combustion engines. In order to evaluate the potential influence of a future H2-based road transportation on the regional air quality in Europe, we implemented H2 in the atmospheric transport and chemistry model LOTOS-EUROS. We simulated the present and future (2020) air quality, using emission scenarios with different proportions of H2 vehicles and different H2 leakage rates. The reference future scenario does not include H2 vehicles, and assumes that all present and planned European regulations for emissions are fully implemented. We find that, in general, the air quality in 2020 is significantly improved compared to the current situation in all scenarios, with and without H2 cars. In the future scenario without H2 cars, the pollution is reduced due to the strict European regulations: annually averaged CO, NOx and PM2.5 over the model domain decrease by 15%, 30% and 20% respectively. The additional improvement brought by replacing 50% or 100% of traditionally-fueled vehicles by H2 vehicles is smaller in absolute terms. If 50% of vehicles are using H2, the CO, NOx and PM2.5 decrease by 1%, 10% and 1% respectively, compared to the future scenario without H2 cars. When all vehicles run on H2, then additional decreases in CO, NOx and PM2.5 are 5%, 40%, and 5% relative to the no-H2 cars future scenario. Our study shows that H2 vehicles may be an effective pathway to fulfill the strict future EU air quality regulations.O3 has a more complicated behavior - its annual average decreases in background areas, but increases in the high-NOx area in western Europe, with the decrease in NOx. A more detailed analysis shows that the population exposure to high O3 levels decreases nevertheless. In all future scenarios, traffic emissions account for only a small proportion of the total anthropogenic emissions, thus it becomes more important to better regulate emissions of non-traffic sectors. Although atmospheric H2 increases significantly in the high-leakage scenarios considered, the additional H2 added into the atmosphere does not have a significant effect on the ground level air pollution in Europe.

Critical loads of cadmium, lead and mercury and their exceedances in Europe
Hettelingh, J.P. ; Schütze, G. ; Vries, W. de; Denier van der Gon, H.A.C. ; Ilyin, I. ; Reinds, G.J. ; Slootweg, J. ; Travnikov, O. - \ 2015
In: Critical Loads and Dynamic Risk Assessments: Nitrogen, Acidity and Metals in Terrestrial and Aquatic Ecosystems / de Vries, W., Hettelingh, J.P., Posch, M., Springer (Environmental Pollution 25) - ISBN 9789401795081 - p. 523 - 546.
In this chapter information is summarized on the assessment of the risk of impacts of cadmium, lead and mercury emissions and related depositions of these metals, with an emphasis on natural areas in Europe. Depositions are compared to critical loads to identify areas in Europe where critical loads are exceeded. Critical loads of cadmium, lead and mercury were based on (i) computations by 18 Parties to the Convention on Long-range Transboundary Air Pollution (LRTAP) and (ii) computations from available data on soil chemistry, meteorology and land cover for the other Parties. Two target years are considered, i.e. 2010 and 2020. Emissions for these years have been assessed in support of the negotiations for the review and possible revision of the Heavy metal protocol (Aarhus 1998). The relationship between emissions, depositions and critical load exceedances is analysed assuming the implementation of abatement techniques under Current LEgislation in 2010 (CLE2010) and in 2020 under Full Implementation of the Aarhus protocol (FI2020). Comparing the critical loads to atmospheric depositions in these years, shows that cadmium deposition is not a widespread risk in either years, that the computed risk of lead deposition affects about 22 and 16¿% of natural European area in 2010 and 2020, respectively, and that mercury deposition is computed to affect an area of more than 74¿% in both years.
Heavy metal emissions, depositions, critical loads and exceedances in Europe
Hettelingh, J.P. ; Sliggers, J. ; Bolcher, M. van het; Denier van der Gon, H. ; Groenenberg, J.E. ; Ilyin, I. ; Reinds, G.J. ; Slootweg, J. ; Travnikov, O. ; Visschedijk, A. ; Vries, W. de - \ 2007
The Hague : VROM-DGM
Human activities release heavy metals into the atmosphere where they are also transported across national boundaries. This has resulted in an enrichment of heavy metals in environments that are far from emission sources. Atmospheric deposition of mercury and lead in particular are calculated to be too high, affecting 77 % and 42 % of European ecosystems respectively in 2000.
Guidelines for planning afforestation of former arable land
Hansen, K. ; Vesterdal, L. ; Muys, B. ; Gilliams, S. ; Rosenqvist, L. ; Salm, C. van der; Elemans, M. ; Denier van der Gon, H.A.C. ; Gundersen, P. ; Johansson, M.B. ; Orshoven, J. van; Heil, G.W. ; Kros, H. ; Bleeker, A. ; Deursen, W. van; Stendahl, J. - \ 2007
In: Environmental Effects of Afforestation in North-Western Europe / Heil, G.W., Muys, B., Hansen, K., Dordrecht : Springer (Plant and Vegetation 1) - ISBN 9781402045677 - p. 249 - 291.
Nitrogen deposition and nitrate leaching following afforestation: Experiences from oak and Norway spruce chronosequences in Denmark, Sweden and the Netherlands.
Rosenqvist, L. ; Hansen, K. ; Vesterdal, L. ; Denier van der Gon, H.A.C. ; Salm, C. van der; Bleeker, A. ; Johansson, M. - \ 2007
In: Environmental Effects of Afforestation in North-Western Europe / Heil, G.W., Muys, B., Hansen, K., Dordrecht : Springer (Plant and Vegetation 1) - ISBN 9781402045677 - p. 79 - 108.
Interception and water recharge following afforestation: Experiences from oak and Norway spruce chronosequences in Denmark, Sweden and the Netherlands.
Salm, C. van der; Rosenqvist, L. ; Vesterdal, L. ; Hansen, K. ; Denier van der Gon, H.A.C. ; Bleeker, A. ; Wieggers, R. ; Toorn, A. van den - \ 2007
In: Environmental Effects of Afforestation in North-Western Europe. Dordrecht : Springer (Plant and Vegetation 1) - ISBN 9781402045677 - p. 53 - 77.
Upscaling regional emissions of greenhouse gases from rice cultivation: methods and sources of uncertainty
Verburg, P.H. ; Bodegom, P.M. van; Denier van der Gon, H.A.C. ; Bergsma, A. ; Breemen, N. van - \ 2006
Plant Ecology 182 (2006)1-2. - ISSN 1385-0237 - p. 89 - 106.
methane emissions - atmospheric methane - water management - ch4 emission - paddy soils - fields - model - china - variability - sensitivity
One of the important sources of greenhouse gases is the emission of methane from rice fields. Methane emission from rice fields is the result of a complex array of soil processes involving plant-microbe interactions. The cumulative effects of these processes at the level of individual plants influence the global atmospheric composition and make it necessary to expand our research focus from small plots to large landscapes and regions. However, present extrapolations (`upscaling¿) are tenuous at best because of methodological and practical problems. The different steps taken to calculate regional emission strengths are discussed and illustrated by calculations for a case-study in the Philippines. The applicability of high quality, process-based, models of methane emission at the level of individual plants is limited for regional analysis by their large data requirements. Simplified models can be used at the regional level but are not able to capture the complex emission situation. Data availability and model accuracy are therefore often difficult to match. Other common sources of uncertainty are the quality of input data. A critical evaluation of input data should be made in every upscaling study to assess the suitability for calculating regional emissions. For the case-study we show effects of differences in input data caused by data source and interpolation technique. The results from the case-study and similar studies in literature indicate that upscaling techniques are still troublesome and a cause of large uncertainties in regional estimates. The results suggest that some of the stumbling blocks in the conventional upscaling procedure are almost impassable in the near future. Based on these results, a plea is made for meso-level measurements to calibrate and validate upscaling methods in order to be better able to quantify and reduce uncertainties in regional emission estimates
Use of measurements and models to improve the national IPCC based assessments of soil emissions of nitrous oxide
Vries, W. de; Kros, J. ; Kuikman, P.J. ; Velthof, G.L. ; Voogd, J.C.H. ; Wieggers, H.J.J. ; Butterbach-Bahl, K. ; Denier van der Gon, H.A.C. ; Amstel, A.R. van - \ 2005
Environmental Sciences 2 (2005)2-3. - ISSN 1569-3430 - p. 217 - 233.
This paper presents various methods to assess nitrous oxide emissions from soils in response to the nitrogen input in agriculture (grassland and arable land) and in forests, using available measurements and results of detailed process-based and more simple and empirical modelling approaches. The measurements and modelling approaches focus on Europe and specifically the Netherlands. Both measurements and model applications indicate that default emission factors for N2O emissions are an underestimate for fertilizer and manure application on organic soils and for N deposition on forests. These results illustrate the potential of measurements and models to improve default IPCC Good Practice Guidance emission factors. Validated detailed process oriented biogeochemical models are furthermore useful to extrapolate results of measurements to other combinations of land use, soil type and management practices, whereas more simplified models have a large potential to extrapolate N2O emission estimates to the regional and national scale. Use of both types of models is essential to improve detail and precision in national N2O emission inventories
Indirect nitrous oxide emissions from the Netherlands
Denier van der Gon, H.A.C. ; Bleeker, A. ; Ligthart, T. ; Kuikman, P.J. ; Groenigen, C.J. van; Hamminga, W. ; Kroeze, C. ; Wilde, H.P.J. de; Hensen, A. - \ 2005
In: Proceedings of the non-CO2 Greenhouse Gas Symposium (NCGG-4), Utrecht, 4-6 July 2005. - Rotterdam : Millpress - ISBN 9059660439 - p. 153 - 160.
Prediction of reducible soil iron content from iron extraction data
Bodegom, P.M. van; Reeven, J. van; Denier van der Gon, H.A.C. - \ 2003
Biogeochemistry 64 (2003)2. - ISSN 0168-2563 - p. 231 - 245.
rice paddy soils - methane production - redox conditions - organic-matter - pyrite formation - reduction - sediments - methanogenesis - aquifer - decomposition
Soils contain various iron compounds that differ in solubility, reducibility and extractability. Moreover, the contribution of the various iron compounds to total iron (Fe) and total Fe concentrations differs highly among soils. As a result, the total reducible Fe content can also differ among soils, and so does the dynamics of iron reduction. These factors complicate the prediction of reducible Fe based on Fe extraction data and hamper the application of process-based models for reduced or waterlogged soils where redox processes play a key-role. This paper presents a theoretical analysis relating reducible to extractable Fe reported in the literature. Predictions made from this theoretical analysis were evaluated in soil incubations using 18 rice paddy soils from all over the world. The incubation studies and the literature study both show that reducible Fe can be related to Fe from some selected, but not all, iron extractions. The combination of measurements for labile Fe(III) oxides (derived from oxalate-extractable Fe) and stabile Fe(III) oxides (derived from dithionite-citrate-extractable Fe) shows highly significant correlations with reducible Fe with high coefficients of determination (r(2) = 0.92-0.95 depending on the definition of stabile Fe(III) oxides). Given the high diversity in rice soils used for the incubations, these regression equations will have general applicability. Application of these regression equations in combination with soil database information may improve the predictive ability of process-based models where soil redox processes are important, such as CH4 emission models derived for rice paddies or wetlands.
Upscaling methane emissions from rice paddies: problems and possibilities
Bodegom, P.M. van; Verburg, P.H. ; Denier van der Gon, H.A.C. - \ 2002
Global Biogeochemical Cycles 16 (2002)2. - ISSN 0886-6236 - p. 1 - 1.
Global methane emission estimates depend highly on the models, techniques, and databases used. Since emissions cannot be measured directly at large scales, it is impossible to judge which estimate is more realistic. In this paper, different aspects of uncertainty in upscaling methane emissions from rice paddies are discussed. These aspects are visualized by a case study on the spatial upscaling of methane emissions from the island of Java, Indonesia. The first aspect concerns process information. An approach to incorporate this information in a simplified but process-based way in predictive models is discussed. Sources of uncertainty include the methane emissions measurements, processes quantification, process simplification, and the use of data transfer functions. Data availability of input parameters, the second aspect, is uncertain because of differences between different data sources, the use of data sources for purposes not originally planned for, and the scale at which data are available. Data interpolation in combination with nonlinear model responses introduces scaling errors, the third aspect. Data accuracy introduced the highest uncertainties in emission estimates but is rarely accounted for in the estimation of global emissions.
Effects of interpolation and data resolution on methane emission estimates from rice paddies
Bodegom, P.M. van; Verburg, P.H. ; Stein, A. ; Adiningsih, S. ; Denier van der Gon, H.A.C. - \ 2002
Environmental and Ecological Statistics 9 (2002). - ISSN 1352-8505 - p. 5 - 26.
rijst - emissie - methaan - geostatistiek - rice - emission - methane - geostatistics
Rice paddies are an important source of the greenhouse gas methane (CH4). Global methane emission estimates are highly uncertain and do not account for effects of interpolation or data resolution errors. This paper determines such scaling effects for the influence of soil properties on calculated CH4 emissions for the island of Java, Indonesia. The effects of different interpolation techniques, variograms and neighbor optimization were tested for soil properties by cross-validation. Interpolated organic carbon values were not significantly different from the original soil samples, in contrast to interpolated soil iron contents. Interpolation of soil properties coupled to a process-based model on CH4 emissions led to a significant change in distribution of calculated CH4 emissions, i.e., the variance decreased. Effects of data resolution were examined by interpolating soil properties to derive data at different data resolutions and then calculating CH4 emissions by applying the process-based model at these resolutions. The soil properties did not differ significantly for different data resolutions, in contrast to calculated CH4 emissions. These scaling effects were caused by the combination of interpolation and a non-linear model. Real scaling effects may even be larger because small-scale variability was not accounted for. Scaling effects, including those caused by small-scale variability, have to be considered to achieve unbiased and less uncertain global CH4 emissions estimates from rice paddies.
Optimizing grain yields reduces CH4 emissions from rice paddy fields
Denier van der Gon, H.A.C. ; Kropff, M.J. ; Breemen, N. van; Wassmann, R. ; Lantin, R.S. ; Aduna, E. ; Corton, T.M. ; Laar, H.H. van - \ 2002
Proceedings of the National Academy of Sciences of the United States of America 99 (2002)19. - ISSN 0027-8424 - p. 12021 - 12024.
emissie - methaan - rijstgronden - natte rijst - opbrengsten - rice soils - emission - methane - flooded rice - yields
Microbial production in anoxic wetland rice soils is a major source of atmospheric CH4, the most important non-CO2 greenhouse gas. Much higher CH4 emissions from well managed irrigated rice fields in the wet than in the dry season could not be explained by seasonal differences in temperature. We hypothesized that high CH4 emissions in the wet season are caused by low grain to biomass ratios. In a screenhouse experiment, removing spikelets to reduce the plants' capacity to store photosynthetically fixed C in grains increased CH4 emissions, presumably via extra C inputs to the soil. Unfavorable conditions for spikelet formation in the wet season may similarly explain high methane emissions. The observed relationship between reduced grain filling and CH4 emission provides opportunities to mitigate CH4 emissions by optimizing rice productivity.
Upscaling methane emissions from wetland rice fields
Woerd, H. van der; Bergsma, A. ; Denier van der Gon, H. ; Janssen, L. ; Leeuwen, H. van; Verhoeven, R. ; Valkengoed, E. van; Wal, J.T. van der - \ 2001
Delft : Netherlands Remote Sensing Board (BCRS), Programme Bureau, Rijkswaterstaat Survey Department - ISBN 9789054113690 - 73
rijst - bodemeigenschappen - bodemchemie - broeikaseffect - methaan - schaalverandering - rice - soil properties - soil chemistry - greenhouse effect - methane - scaling
Upscaling and downscaling of regional methane sources - rice agriculture as a case study
Breemen, N. van; Denier van der Gon, H. ; Veldkamp, T. ; Verburg, P. ; Bodegom, P.M. van; Goudriaan, J. ; Leffelaar, P.A. ; Stams, F. ; Houweling, S. ; Lelieveld, J. ; Slanina, S. ; Zhang, Y. - \ 2001
Bilthoven, the Netherlands : RIVM (Dutch National Research Programme on Global Air Pollution and Climate Change 410 200 070) - ISBN 9789058510495 - 133
rijst - bodemeigenschappen - bodemchemie - broeikaseffect - methaan - schaalverandering - verzegelen - luchtverontreiniging - azië - rice - soil properties - soil chemistry - greenhouse effect - methane - scaling - sealing - air pollution - asia
Sulfate-containing amendments to reduce methane emissions from rice fields: mechanisms, effectiveness and costs
Denier van der Gon, H.A. ; Bodegom, P.M. van; Wassman, R. ; Lantin, R.S. ; Metra-Corton, T.M. - \ 2001
Mitigation and Adaptation Strategies for Global Change 6 (2001). - ISSN 1381-2386 - p. 71 - 89.
Application of sulfate-containing amendments is often suggested as a mitigation option to reduce methane (CH4) emissions from rice ( Oryza) fields. This paper discusses the mechanism and potential of this mitigation option, reviews the relevant experimental data, and presents first, indicative costs of application. CH4 emission data for rice fields with sulfate-containing amendments are compiled to reinterpret the resulting reduction in CH4 emission and find a general relationship between emission reduction and amount of sulfate applied. The reduction in CH4 emission depends on the amount of sulfate applied. However, absolute emission reduction is location specific and cannot be derived from the amount of sulfate (SO2-4) applied only. We established a logarithmic relationship, across locations, between SO2-4 application and fractional emission reduction relative to the emission of the non-amended control field. Recycling of SO2-4 in the rhizosphere was essential to explain the observed reductions in CH4 emission for a number of the experiments. The cost of applying SO2-_4-containing fertilizers varies across countries and depends on local fertilizer prices. Since a fractional reduction is obtained, the cost-efficiency in terms of CH4 mitigation per unit of SO2-4 applied will be highest in high-emitting rice production systems. Provided the proper target areas are selected, the cost of SO2-4-containing fertilizer as a mitigation option to reduce CH4 emissions in rice fields is estimated at 5–10 US dollar per Mg CO2-equivalent.
Spatial and temporal dynamics of methane emissions from agricultural sources in China
Verburg, P.H. ; Denier van der Gon, H.A.C. - \ 2001
Global Change Biology 7 (2001). - ISSN 1354-1013 - p. 31 - 47.
Agricultural activities contribute significantly to the global methane budget. Agricultural sources of methane are influenced by land-use change, including changes in agricultural area, livestock keeping and agricultural management practices. A spatially explicit inventory of methane emissions from agriculture is made for China taking the interconnections between the different agricultural sources into account. The influence of land-use change on methane emissions is studied by linking a dynamic land-use change model with emission calculations. The land-use change model calculates changes in rice area and livestock numbers for a base-line scenario. Emissions are calculated for 1991 based on land-use statistics and for 2010 based on simulated changes in land-use patterns. Emissions from enteric fermentation and manure management are based on emission factors, while emissions from rice paddies involve the calculation of total organic carbon added to rice paddy soils and assume that a constant fraction is emitted as methane. Spatial patterns of emissions are presented for the different sources. For the land-use scenario considered it is expected that total methane emissions from agricultural sources in China increase by 11 hile the relative contribution of rice fields to the emission decreases. Emissions from manure management are expected to become more important. These results indicate that agencies should anticipate changes in source strengths as a consequence of land-use changes when proposing mitigation strategies and future national greenhouse gas budgets
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