Methodiek voor berekening van ammoniakemissie uit de landbouw in Nederland (2009)
Velthof, G.L., Groenestein, C.M., Hoogeveen, M.W., Huijsmans, J.F.M.
Maatregelen om ammoniakemissie bij bovengronds toedienen van mest te beperken (2009)
Tamminga, S., Sebek, L.B.J., Bussink, W., Huijsmans, J.F.M., Velthof, G.L.
P. C. Stolk, E. J. Moors, A. Hensen, G. L. Velthof, P. Kabat
Chambers are widely used to measure surface fluxes of nitrous oxide (N<sub>2</sub>O). Usually linear regression is used to calculate the fluxes from the chamber data. Non-linearity in the...
Schils, R.L.M., Velthof, G.L., Kuikman, P.J., Oudendag, D.A., Oenema, O.
Animal production systems are large and complex sources of greenhouse gases (GHG), especially nitrous oxide (N2O) and methane (CH4). Emissions from these systems are expected to rise over the coming...
Bertora, C., Alluvione, F, Zavattaro, L, Velthof, G.L., Grignani, C
The treatment of manures may improve their agricultural value and environmental quality, for instance with regards to greenhouse gases mitigation and enhancement of carbon (C) sequestration. The...
Schils, R.L.M., Velthof, G.L., Kuikman, P.J.
Fertiliser and manure application are important sources of nitrous oxide (N2O) emissions from agricultural soils. The current default IPCC emission factor of 1.0% is independent of the type of...
Decomposition and accumulation of organic matter in soil; comparison of some models (2008)
Janssen, B.H., Heesmans, H.I.M., Conijn, J.G., Velthof, G.L., Chardon, W.J.
Indicator voor stikstofmineralisatie in gescheurd grasland; synthese (2008)
Velthof, G.L., Hoving, I.E., Dekker, P.H.M., Reijneveld, A., ...
Toetsdiepte voor nitraat : synthese onderzoek 2008 (2008)
Groenendijk, P., Griffioen, J., Velthof, G.L., Janssen, G., Fraters, B.
"EURURALIS 2.0 Technical background and indicator documentation" (2008)
Balkema, A., Bakker, M, Banse, M.A.H., Bouwman, L.A., Eickhout, B., ...
Estimation of nitrogen losses via denitrification from a heavy clay soil under grass (2007)
Dolfing, J., Heinen, M., Velthof, G.L.
Denitrification is an important pathway for nitrogen (N) loss from agricultural soils, but measured field data on denitrification in clay soils are scarce. The objective of the present research was...
Schröder, J.J., Aarts, H.F.M., Schils, R.L.M., Velthof, G.L., ...
Properly managed manures have a high fertilizer equivalency and are thus a valuable source of nutrients in forage production systems. An efficient utilization of these nutrients, however, is limited...
Leaching of solutes from an intensively managed peat soil to surface water (2007)
Droogers, P., Velthof, G.L., Oenema, O.
In many peat land areas in The Netherlands target concentrations for nitrogen (N) and phosphorus (P) in surface water are exceeded. A considerable, but poorly quantified, fraction, of the N and P...
Gebruiksnormen van meststoffen in de praktijk, getoetst in 2004 en 2005 (2007)
Oenema, J., Assinck, F.B.T., Verloop, J., Velthof, G.L., Aarts, F.
Grassland renovation in the Netherlands; agronomic, environmetal and economic issues (2007)
Schils, R.L.M., Aarts, H.F.M., Bussink, D.W., Conijn, J.G., Corre, V.J., ...
Landbouwpraktijk en waterkwaliteit op landbouwbedrijven aangemeld voor derogatie (2007)
Fraters, B., Reijs, J.W., Boumans, L.J.M., Aarts, H.F.M., Daatselaar, C.H.G., ...
Nutrient losses from manure management in the European Union (2007)
Oenema, O., Oudendag, D.A., Velthof, G.L.
Manure management systems are conducive to nutrient and carbon losses, but the magnitude of the loss highly depends on the nutrient element, the manure management system and the environmental...
Quantification of ammonia emission and nitrate leaching in EU-27 using MITERRA-EUROPE (2007)
Velthof, G.L., Oudendag, D.A., Witzke, H.P., Asman, W.A.H., Klimont, Z., Oenema, O.
Production of N2O in the soil - more than nitrification and denitrification (2007)
Kool, D.M., Wrage, N., Oenema, O., Velthof, G.L., Kuikman, P.J.
Fraters, B., Boumans, L.J.M., Gast, F.L.F., Griffioen, J., Klaver, G.T., ...
Het verlagen van de toetsdiepte voor nitraat in het grondwater in zandgebieden van de bovenste meter van het grondwater naar de bovenste vijf meter, blijkt niet opportuun. Het verlagen van de...
In juli 2004 heeft Nederland overeenstemming bereikt met de Europese Commissie over het Derde Nederlandse Actieprogramma (2004-2009). Op zand- en lössgrond mag vanaf 2006 de graszode alleen tussen 1...
Een nieuwe toetsdiepte voor nitraat in grondwater? (2006)
Fraters, B., Boumans, L.J.M., Gast, L.F.L., Griffioen, J., Klaver, G.T., ...
Urine patches from cattle and sheep on pastures represent considerable, highly localized N applications. Subsequent nitrification and denitrification of the nitrogenous compounds may result in high...
Gaseous nitrogen and carbon losses from pig manure derived from different diets (2005)
Velthof, G.L., Nelemans, J.A., Oenema, O., Kuikman, P.J.
Received for publication July 23, 2004. Manipulation of the diets of pigs may alter the composition of the manure and thereby the environmental and agricultural qualities of the manure. Laboratory...
Velthof, G.L., Vos, A., Kuikman, P.J.
Urine patches in pastures rank among the highest sources of the greenhouse gas nitrous oxide (N2O) from animal production systems. Previous laboratory studies indicate that N2O emissions for urine-N...
Subsoil 15N-N2O concentrations in a sandy soil profile after application of 15N-fertilizer (2005)
Georgius, P.J., Hummelink, E.W.J., Velthof, G.L., Zwart, K.B.
Trends in global nitrous oxide emissions from animal production systems (2005)
Oenema, O., Wrage, N., Velthof, G.L., Dolfing, J., Kuikman, P.J.
Wastes from animal production systems contribute as much as 30–50% to the global N2O emissions from agriculture, but relatively little attention has been given on improving the accuracy of the...
Effect van tijdstip van scheuren op N-mineralisatie en -uitspoeling (2005)
Velthof, G.L., Conijn, J.G., Aarts, H.F.M., Voogd, J.C.H., Groenendijk, P., ...
Conceptprotocol voor bemesting op basis van een bodemanalyse (2005)
Velthof, G.L., Dekker, P.H.M., Hoving, I.E., Reijneveld, A., Aarts, H.F.M.
Subsoil 15N-N2O concentrations in a sandy soil profile after application of 15N-fertilizer (2005)
Georgius, P.J., Hummelink, E.W.J., Velthof, G.L., Zwart, K.B.
Studies on emissions of nitrous oxide (N2O) from agricultural soils mostly focus on fluxes between the soil and the atmosphere or are limited to the atmosphere in the topsoil. However, in soils with...
De bodemgesteldheid van de referentiepercelen : resultaten van veld- en laboratoriumonderzoek (2005)
Sturen op nitraat: nitraatconcentraties in het grondwater en mogelijke indicatoren (2005)
Smit, A.L., Boels, D., ...
Kros, J., Kuikman, P.J., Velthof, G.L., Voogd, J.C.H., Wieggers, H.J.J., ...
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...
De Vries, W., Kros, J., Kuikman, P.J., Velthof, G.L., Voogd, J.C.H., Wieggers, H.J.J., ...
Environmental Sciences, 2(2005) S.217-33
Wrage, N., Velthof, G.L., Laanbroek, H.J., Oenema, O.
Nitrifier denitrification is the reduction of NO2- to N2 by nitrifiers. It leads to the production of the greenhouse gas nitrous oxide (N2O) as an intermediate and possible end product. It is not...
Hoving, I.E., Radersma, S., ...
In het project STuren OP NITraat wordt gezocht naar verbanden tussen zogenaamde kandidaat-indicatoren voor de nitraatbelasting van het grondwater. Na analyse van de gegevens van twee meetseizoenen...
Gebruiksnormen bij verschillende landbouwkundige en milieukundige uitgangspunten (2004)
Schröder, J.J., Aarts, H.F.M., ...
Kuikman, P.J., Velthof, G.L., Walvoort, D.J.J., ...
In het kader van het Reductie Plan Overige Broeikasgassen (ROB Landbouw) zijn de mogelijkheden voor het verminderen van de emissie van lachgas (N2O) bij optimalisern van beweiding bestudeerd. In de...
Wrage, N., Velthof, G.L., Oenema, O., Laanbroek, H.J.
Autotrophic ammonia-oxidizing bacteria produce nitrous oxide (N2O) as a by-product of nitrification or as an intermediate of nitrifier denitrification. In soil incubations, acetylene (C2H2) and large...
Kasper, G.J., Velthof, G.L., Kuikman, P.J.
Intensive dairy farming systems are a large source of emission of the greenhouse gas nitrous oxide (N2O), because of high nitrogen (N) application rates to grasslands and silage maize fields. The...
Nitrogen rate, surplus or residue? Performance of selected indicators for nitrate leaching (2004)
Smit, A., Velthof, G.L., ...
Smit, A., Hoving, I.E., ...
In het project `Sturen op Nitraat¿ wordt gezocht naar indicatoren waarmee de nitraatconcentratie in het grondwater kan worden voorspeld. Uit een analyse van de meetresultaten van drie meetseizoenen...
Denitrificatie in de zone tussen bouwvoor en het bovenste grondwater in zandgronden (2004)
Velthof, G.L., Brouwer, F., Fraters, B., Groenendijk, P., ...
Er zijn grote variaties in de nitraatconcentratie in het bovenste grondwater van uitspoelings-gevoelige zandgronden geconstateerd. Deze variaties worden waarschijnlijk veroorzaakt door...
Achtergronddocument bij enkele vragen van de evaluatie Meststoffenwet 2004 (2004)
In de evaluatie van de Meststoffenwet 2004 wordt verslag uitgebracht aan het kabinet, Tweede Kamer en andere belanghebbenden van de werking van de Meststoffenwet sinds de invoering hierin van het...
Effects of grassland cultivation on N and C cycles and soil quality dynamics (2004)
Vertès, F., Hatch, D.J., Velthof, G.L., Abiven, S., Hopkins, A., Springob, G.
Smit, A., Hoving, I.E., ...
Binnen het project ¿Sturen op Nitraat¿ zijn regressiemodellen ontwikkeld. In dit rapport wordt op verschillende manieren getoetst hoe nauwkeurig de nitraatconcentratie uit waarnemingen aan de...
Denitrification in agricultural soils in the Netherlands (2004)
Zwart, K.B., Velthof, G.L., Heinen, M., Grift, B., Boumans, L.
Wrage, N., Velthof, G.L., Oenema, O., Laanbroek, H.J.
Autotrophic ammonia-oxidizing bacteria produce nitrous oxide (N2O) as a by-product of nitrification or as an intermediate of nitrifier denitrification. In soil incubations, acetylene (C2H2) and large...
Gegevensverzameling Sturen op nitraat; op zoek naar een indicator (2003)
Smit, A., Chardon, W.J., ...
In dit rapport worden de onderzoeksopzet en de bemonsteringsmethodieken van het project Sturen op nitraat beschreven. Het monitoringsysteem, de stratificering en de verdeling van proefplekken over de...
Mineralisatie en denitrificatie zijn bodemprocessen die een groot effect hebben op de hoeveelheid voor het gewas beschikbare stikstof en de stikstofuitspoeling naar grond- en oppervlaktewater....
Hoving, I.E., ...
In het project STuren OP NITraat wordt gezocht naar verbanden tussen zogenaamde kandidaat-indicatoren voor de nitraatbelasting van het grondwater. Na analyse van de gegevens van één meetseizoen...
Voorjaarsinzaai pakt goed uit in 2002 (2003)
Grasland wordt bij voorkeur gescheurd in het najaar. De huidige wetgeving staat scheuren tot uiterlijk 15 september toe. Dit betekent dat eind augustus de laatste snede gewonnen kan worden en dat de...
Mineralisatie en denitrificatie zijn bodemprocessen die een groot effect hebben op de hoeveelheid voor het gewas beschikbare stikstof en de stikstofuitspoeling naar grond- en oppervlaktewater....
The Netherlands has submitted a derogation under the Nitrate Directives to the European Union (EU) in 2000. In the final opinion by a group of experts about the Dutch derogation, recommendations on...
Nitrous oxide emission from soils amended with crop residues (2002)
Velthof, G.L., Kuikman, P.J., Oenema, O.
Crop residues incorporated in soil are a potentially important source of nitrous oxide (N2O), though poorly quantified. Here, we report on the N2O emission from 10 crop residues added to a sandy and...
Grassland renovation in the Netherlands; agronomic, environmental and economic issues (2002)
Schils, R.L.M., Aarts, H.F.M., Bussink, D.W., Conijn, J.G., Corré, W.J., ...
Velthof, G.L., Dolfing, J., Kasper, G.J., ...
In het kader van het reductieplan overige broeikasgassen (ROB Landbouw) zijn de mogelijkheden voor het verminderen van de emissie van lachgas (N2O) uit bemeste landbouwgronden bestudeerd. In de...
Dolfing, J., Velthof, G.L., Kuikman, P.J.
In het kader van het reductieplan overige broeikasgassen (ROB Landbouw) zijn de mogelijkheden voor het verminderen van de emissie van lachgas (N2O) als gevolg van het toepassen van gewasresten...
Velthof, G.L., Oenema, O., Kuikman, P.J.
The decision support system MITERRA-DSS was developed to quantify the effects of measures to mitigate carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4) emissions from agriculture in The...
Role of nitrifier denitrification in the production of nitrous oxide (2001)
Wrage, N., Velthof, G.L., Oenema, O.
Nitrifier denitrification is the pathway of nitrification in which ammonia (NH3) is oxidized to nitrite (NO2−) followed by the reduction of NO2− to nitric oxide (NO), nitrous oxide (N2O) and...
Effects of ageing and cultivation of grassland on soil nitrogen (2001)
Nitrogen losses from agriculture in the Netherlands have to be strongly decreased because of national and international policy (e.g. Nitrate Directive). The cultivation of grassland when grassland is...
Regionaal nutriëntenmanagement; een verkenning van perspectieven en beperkingen (2001)
De van oudsher monofunctionele landbouw verandert steeds meer in een multifunctionele landbouw, waarin meerdere functies van het landelijke gebied worden verweven. Met behulp van regionaal...
Oenema, O., Velthof, G.L., Kuikman, P.J.
Agricultural activities greatly contribute to the global net flux of CH4, N2O and CO2 from the terrestrial biosphere into the atmosphere. For CH4 and N2O, the net contribution is in the order of...
Beperking van lachgasemissie uit gewasresten; een systeemanalyse (2000)
In het kader van het reductieplan overige broeikasgassen (ROB) worden de mogelijkheden bestudeerd voor het verminderen van de lachgasemissie uit gewasresten die na de oogst in de bodem achterblijven....
Beperking van lachgasemissie uit bemeste landbouwgronden; een systeemanalyse (2000)
Velthof, G.L., Schils, R.L.M., Monteny, G.J., Kuikman, P.J.
In het kader van het reductieplan overige broeikasgassen (ROB) worden de mogelijkheden bestudeerd voor het verminderen van de lachgasemissie uit bemeste landbouwgronden. In een bureaustudie is een...
Beperking van lachgasemissie uit beweid grasland; een systeemanalyse (2000)
Velthof, G.L., Holshof, G., Kuikman, P.J.
In het kader van het reductieplan overige broeikasgassen (ROB) worden de mogelijkheden bestudeerd voor het verminderen van de lachgasemissie uit beweid grasland. In een bureaustudie zijn de...
Temporal stability of spatial patterns of nitrous oxide fluxes from sloping grassland (2000)
Velthof, G.L., Gebauer, G., Pietrzak, S., Jarvis, S.C., Pinto, M., ...
Insight into the temporal and spatial variability of nitrous oxide (N2O) fluxes from soils is required to set up efficient sampling protocols of N2O fluxes and to set up strategies to reduce N2O...
Velthof, G.L., Neeteson, J.J., Oenema, O.
De Europese Commissie heeft Nederland in 1999 in gebreke gesteld betreffende de implementatie van wetgeving in het kader van de Nitraatrichtlijn. Een van de punten hierbij is dat Nederland de netto...
Velthof, G.L., Bannink, A., Oenema, O., Spoelstra, S.F.
Optimization of the utilization of nutrients in animal manures requires a whole-chain approach, from the animal feed via the animal and animal manure to the soil and crop. A literature study was...
Forfaitaire waarden voor gasvormige stikstofverliezen uit stallen en mestopslagen; gew. druk (2000)
Oenema, O., Velthof, G.L., Verdoes, N., Monteny, G.J., Bannink, A., ...
De Europese Nitraatrichtlijn stelt grenzen aan de hoeveelheid stikstof die via dierlijke mest op landbouwgronden mag worden toegediend. De Nederlandse mestwetgeving schrijft bovendien voor dat...
Kuikman, P.J., Corré, W.J., Kroes, J.G., Vellinga, T.V., ...
In Nederland draagt de agrarische sector in belangrijke mate (35-40%) bij aan de nationale emissie van lachgas. De lachgasemissie uit landbouw bedraagt naar schatting negen miljoen ton...
Postma, R., Velthof, G.L., Oenema, O.
A study was conducted to investigate the potential of using mixtures of cattle slurry with cheap urea (U) or urea-ammonium nitrate (UAN). The kinetics of NH3 volatilization, nitrous oxide (N2O)...
Comparison of nitrogen mineralization indices for arable land (2000)
Velthof, G.L., Oenema, O., Nelemans, J.A.
Nitrogen (N) efficiency in arable cropping systems can be improved when the expected N mineralization in soil during the growing season is accounted for in the N fertilizer recommendation. There are...
Temporal stability of spatial patterns of nitrons oxide fluxes from sloping grassland (2000)
Velthof, G.L., Gebauer, G., Pietrzak, S., Jarvis, S.C., Pinto, M., ...
Insight into the temporal and spatial variability of nitrous oxide (N2O) fluxes from soils is required to set up efficient sampling protocols of N2O fluxes and to set up strategies to reduce N2O...
Emissions of CO2, CH4 and N2O from pasture on drained peat soils in The Netherlands (1999)
Langeveld, C.A., Segers, R., Dirks, B.O.M., Velthof, G.L., Hensen, A.
Nitrous oxide emission from intensively managed grasslands (1998)
The N2O emission from intensively managed grasslands in the Netherlands, and possible options to mitigate N2O emission, were studied. The study consisted of field studies in which the N2O emission...
Nitrous oxide emission from dairy farming systems in the Netherlands (1997)
A large part of the nitrogen (N) input in dairy farming systems in the Netherlands is lost from the system via N leaching and volatilization of gaseous N compounds, including the greenhouse gas...
Nitrous oxide emission from dairy farming systems in the Netherlands (1997)
A large part of the nitrogen (N) input in dairy farming systems in the Netherlands is lost from the system via N leaching and volatilization of gaseous N compounds, including the greenhouse gas...
Emissions of CO2, CH4 and N2O from pasture on drained peat soils in the Netherlands. (1997)
Langeveld, C.A., Segers, R., Dirks, B.O.M., Velthof, G.L., Hensen, A.
Nitrous oxide emission from intensively managed grassland. (1997)
http://library.wur.nl/wda/abstracts/ab2265.html
Nitrous oxide emission from dairy farming systems in the Netherlands. (1997)
A large part of the nitrogen (N) input in dairy farming systems in the Netherlands is lost from the system via N leaching and volatilization of gaseous N compounds, including the greenhouse gas...
G.L. Velthof, J.G. Koops, J.H. Duyzer, O. Oenema
Three measurement campaigns were carried out to answer questions related to the factors controlling variations in nitrous oxide (N2O) fluxes from intensively managed grassland on peat soil,...
G.L. Velthof, J.G. Koops, J.H. Duyzer, O. Oenema
Three measurement campaigns were carried out to answer questions related to the factors controlling variations in nitrous oxide (N2O) fluxes from intensively managed grassland on peat soil,...
Velthof, G.L., Jarvis, S.C., Stein, A., Allen, A.G., Oenema, O.
Fluxes of nitrous oxide (N2O) were measured in mown and intensively-grazed plots on a slightly-sloping, poorly-drained clay soil, using 144 flux chambers on four consecutive days. We tested the...
Seasonal variations in nitrous oxide losses from managed grasslands in the Netherlands. (1996)
Velthof, G.L., Brader, A.B., Oenema, O.
Seasonal and interannual variations in nitrous oxide (N2O) losses from agricultural soils hamper the accurate quantification of the N2O source strength of these soils. This study focuses on a...
Emissions of CO2, CH4 and N2O from pasture on drained peat soils in the Netherlands. (1996)
Langeveld, C.A., Segers, R., Dirks, B.O.M., Velthof, G.L., Hensen, A.
Velthof, G.L., Koops, J.G., Duyzer, J.H., Oenema, O.
Three measurement campaigns were carried out to answer questions related to the factors controlling variations in nitrous oxide (N2O) fluxes from intensively managed grassland on peat soil,...
Accurate estimates of total nitrous oxide (N2O) losses from grasslands derived from flux-chamber measurements are hampered by the large spatial and temporal variability of N2O fluxes from these...
Intensively managed grasslands are potentially a large source of nitrous oxide (N2O) in the Netherlands because of the large nitrogen (N) input and the fairly wet soil conditions. To quantify the...
Nitrous oxide emission from managed grasslands in The Netherlands, Scotland and Belgium. (1994)
Velthof, G.L., Oenema, O., McTaggart, I.P., Clayton, H., Smith, K.A., ...
Denitrification in nitric-acid-treated cattle slurry during storage (1993)
Lowering the pH of cattle slurry with HNO3 was used to reduce NH3 volatilization during storage and after application. Incubation studies were carried out to examine possible NO3 losses and N2O...
Nitrous oxide (N2O) fluxes from cattle slurry after surface application to grassland were measured under semi-controlled environmental conditions during three periods in 1991. Three types of cattle...
Denitrification in nitric-acid-treated cattle slurry during storage (1993)
Lowering the pH of cattle slurry with HNO3 was used to reduce NH3 volatilization during storage and after application. Incubation studies were carried out to examine possible NO3 losses and N2O...
Nitrous oxide (N2O) fluxes from cattle slurry after surface application to grassland were measured under semi-controlled environmental conditions during three periods in 1991. Three types of cattle...
Denitrification in nitric-acid-treated cattle slurry during storage. (1993)
Lowering the pH of cattle slurry with HNO3 was used to reduce NH3 volatilization during storage and after application. Incubation studies were carried out to examine possible NO3 losses and N2O...
Nitrous oxide (N2O) fluxes from cattle slurry after surface application to grassland were measured under semi-controlled environmental conditions during three periods in 1991. Three types of cattle...
Lachgasemissie uit grasland (1993)
Het Nederlands Meststoffen Instituut (NMI) is in het voorjaar 1992 gestart met onderzoek naar de lachgasemissie uit grasland.
Emissions of ammonia, nitrous oxide and methane from cattle slurry (1993)
Oenema, O., Velthof, G.L., Bussink, D.W.
Measurements were made of N2O and CH4 production during a 6 month storage (15 degrees C) period from either unamended cattle slurry or slurry unamended with HNO3 to pH 4.5 or pH 6. After storage the...
Stikstofverliezen en lachgasemissie uit aangezuurde dunne rundermest (1993)
Toevoeging van salpeterzuur aan dunne mest is een effectieve methode om ammoniakvervluchtiging uit mest te verminderen bij opslag. Dunne mest vlak voor de toediening aanzuren voorkomt ook...
Nitrous oxide (N2O) fluxes from cattle slurry after surface application to grassland were measured under semi-controlled environmental conditions during three periods in 1991. Three types of cattle...
Velthof, G.L., Postmus, J., Prins, W.H.
Ammonia (NH3) volatilization from urea and calcium ammonium nitrate (CAN) broadcast to permanent grassland on a clay soil was measured in-situ, using a system of wind-tunnels. When CAN was applied...