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.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    Turbulent exchange of energy, momentum, and reactive gases between high vegetation and the atmospheric boundary layer
    Shapkalijevski, M.M. - \ 2017
    Wageningen University. Promotor(en): M.C. Krol; J. Vilà-Guerau de Arellano, co-promotor(en): A.F. Moene; H.G. Ouwersloot. - Wageningen : Wageningen University - ISBN 9789463430845 - 163
    vegetation - atmospheric boundary-layer - atmosphere - energy exchange - gases - canopy - meteorology - vegetatie - atmosferische grenslaag - atmosfeer - energie-uitwisseling - gassen - kroondak - meteorologie

    This thesis deals with the representation of the exchange of energy, momentum and chemically reactive compounds between the land, covered by high vegetation, and the lowest part of the atmosphere, named as atmospheric boundary layer (ABL).

    The study presented in this thesis introduces the roughness sublayer (RSL), the layer just above the tall vegetation canopy in which the atmospheric flow is directly affected by the presence of roughness elements, as an important part of the ABL system. Our focus is on the exchange of the thermodynamic, as well as the chemical properties of the boundary layer. Our methodology combines observational analysis using high resolution meteorological and chemistry measurements from the Canopy Horizontal Array Turbulence Study (CHATS) and modelling framework of the soil-vegetation-atmospheric boundary layer system. The systematic investigation in this thesis showed the relevance of the RSL for the turbulent exchange processes between the atmosphere and the land surface characterized by high vegetation. More specifically, we explained and discussed how the turbulence parameterization within the roughness sublayer is strongly dependent on canopy-phenology (canopy leaf state) and atmospheric-stability changes, and provided parameterization formulations for . Our modelling analysis further showed that the CHATS boundary-layer dynamics are mainly affected and controlled by the large-scale processes (advection and subsidence), while the effect of the canopy and the roughness sublayer were relatively small. Near the canopy top however, the the canopy had a significant impact on the modelled boundary layer state variables (wind speed, potential temperature and specific humidity) and the corresponding turbulent transfer coefficients (drag coefficients for momentum and scalars), as supported by the observations. With respect to the exchange of reactive compounds, we diagnosed twice-larger magnitude of the ozone deposition fluxes when the roughness sublayer effects are taken into account in the flux-gradient relationship, compared to the method which neglects these effects. Thus, neglecting the roughness sublayer effects in the surface flux parameterization schemes of ozone in atmosphere-chemistry models can lead to significant overestimation of the ozone diurnal mixing ratio in the boundary layer.

    By studying the high vegetation-atmosphere exchange processes, their quantification, and testing methods for their parameterization, we contribute to improve our understanding and representation of the roughness sublayer-atmospheric boundary-layer system.

    Estimation of abraham solvation equation coefficients for hydrogen bond formation from abraham solvation parameters for solute activity and basicity
    Noort, P.C.M. van - \ 2013
    Chemosphere 90 (2013)2. - ISSN 0045-6535 - p. 344 - 348.
    free-energy relationship - 298 k - partition-coefficients - organic-compounds - ionic liquids - lfer analysis - solubility - vapors - gases - water
    Abraham solvation equations find widespread use in environmental chemistry and pharmaco-chemistry. The coefficients in these equations, which are solvent (system) descriptors, are usually determined by fitting experimental data. To simplify the determination of these coefficients in Abraham solvation equations, this study derives equations, based on Abraham solvation parameters for hydrogen acidity and basicity of the solvents involved, to estimate the value of the coefficients for hydrogen bond formation. These equations were applied to calculate Abraham solvation parameters for hydrogen acidity and basicity for polyoxymethylene, polyacrylate, sodium dodecylsulfate, some ionic liquids, alkanoyl phosphatidyl cholines, and lipids for which fitted values for Abraham coefficients for hydrogen bond formation were available
    Biotrickling filter for the treatment of exhaust air from a pig rearing building: Ammonia removal performance and its fluctuations
    Melse, R.W. ; Ploegaert, J.P.M. ; Ogink, N.W.M. - \ 2012
    Biosystems Engineering 113 (2012)3. - ISSN 1537-5110 - p. 242 - 252.
    nitrous-acid - inhibition - nitrification - operations - gases - odor - nh3
    The removal of ammonia (NH3) by a full scale packed-bed biotrickling filter (packing volume: 3.8 m3; water buffer tank: 20 m3) under fluctuating loading conditions was studied. The unit was operated at an animal house for treatment of exhaust air at an average air contact time of 1.2 s. Continuous long-term ammonia measurements showed average inlet and outlet air concentrations of 14 ppm and 2.4 ppm, respectively, and a removal efficiency of 82%. The average temperature of the water was 16 °C, the pH 6.6, the ammonium concentration 1.9 g N l-1, and the nitrate concentration 1.8 g N l-1; no nitrite was detected. The average ammonia loading and removal rate were 29 and 24 g NH3 m-3 h-1, respectively. A daily and seasonal pattern could be observed in the ammonia removal performance. With increasing outside temperature ammonia loading rate, ammonia removal rate, and ammonia outlet concentration increased, resulting in a net decrease of the ammonia removal efficiency. This phenomenon might be explained by the existence of equilibrium between the ammonia concentration in the outlet air and the concentration of dissolved ammonia in the water, which is influenced by fluctuating air and water temperature. A nitrogen balance indicated that 86% of the removed ammonia-N was discharged or accumulated in the water as ammonium and nitrate, and 5% was emitted as nitrous oxide (N2O). The fluctuating removal patterns that were found suggest that current regulatory performance monitoring practices need to be improved
    Rural residential CO2 emissions in China: Where is the major mitigation potential?
    Liu Wenling, Wenling ; Wang Can, ; Mol, A.P.J. - \ 2012
    Energy Policy 51 (2012). - ISSN 0301-4215 - p. 223 - 232.
    biomass - combustion - gases
    Despite high-speed economic growth in recent decades, rural China is still confronted with persisting poverty, alongside energy shortages and environmental degradation. In tackling climate change, carbon emissions from rural energy use have been given little attention up till now. This paper provides an analysis of rural residential CO2 emissions in China based on diverse accounting methods, and employs the geographic information system (GIS) to map emissions of each province. Identifying the major emission sources could provide a basis for understanding the potential for greenhouse gas emission reduction and proposing related policy recommendations. The results showed that the largest GHG mitigation potential can be found at traditional biomass use among residents. Four emission reduction policy strategies are identified: (i) shifting to commercial energy; (ii) furthering the use of decentralized renewable energy options; (iii) commercializing biomass energy via biomass power generation, biomass briquettes and biogas production; (iv) improving the combustion efficiency of traditional biomass use in household appliances. Differences in resource endowment and local economic conditions created varied levels of rural residential greenhouse gas emission, the related mitigation potential, and the kinds of strategies and policies that need to be developed in the Chinese provinces.
    Solvation thermodynamics and the physical-chemical meaning of the constant in Abraham solvation equations
    Noort, P.C.M. van - \ 2012
    Chemosphere 87 (2012)2. - ISSN 0045-6535 - p. 125 - 131.
    free-energy relationship - organic solutes - partition constant - 298 k - bioconcentration factor - stationary-phase - ionic liquids - lfer analysis - enthalpy - gases
    braham solvation equations find widespread use in environmental chemistry. Until now, the intercept in these equations was determined by fitting experimental data. To simplify the determination of the coefficients in Abraham solvation equations, this study derives theoretical expressions for the value of the intercept for various partition processes. To that end, a modification of the description of the Ben-Naim standard state into the van der Waals volume is proposed. Differences between predicted and fitted values of the Abraham solvation equation intercept for the enthalpy of solvation, the entropy of solvation, solvent-water partitioning, air-solvent partitioning, partitioning into micelles, partitioning into lipid membranes and lipids, and chromatographic retention indices are comparable to experimental uncertainties in these values.
    WKK-rookgassen: een bedreiging voor biologische bestrijding? : geen bewijs voor negatieve effecten op biologische bestrijders
    Messelink, G.J. ; Bloemhard, C.M.J. - \ 2012
    Onder Glas 9 (2012)2. - p. 37 - 37.
    teelt onder bescherming - glastuinbouw - warmtekrachtkoppeling - schadelijke dampen - gassen - organismen ingezet bij biologische bestrijding - oorzakelijkheid - landbouwkundig onderzoek - paprika's - groenten - protected cultivation - greenhouse horticulture - cogeneration - fumes - gases - biological control agents - causality - agricultural research - sweet peppers - vegetables
    Met het doseren van CO2 vanuit WKK-installaties in kassen komt altijd een laag percentage rookgassen mee. De laatste jaren is er veel aandacht geweest voor de mogelijke negatieve effecten van deze rookgassen op gewassen. De effecten op andere organismen, zoals plantpathogenen, plagen en natuurlijke vijanden zijn onbekend. Wageningen UR Glastuinbouw heeft oriënterend gekeken of rookgassen de plaagbestrijding in paprika beïnvloeden.
    Inverse modelling of European N2O emissions: assimilating observations from different networks
    Corazza, M. ; Bergamaschi, P. ; Vermeulen, A.T. ; Krol, M.C. - \ 2011
    Atmospheric Chemistry and Physics 11 (2011)5. - ISSN 1680-7316 - p. 2381 - 2398.
    nitrous-oxide - atmospheric methane - ozone - gases
    We describe the setup and first results of an inverse modelling system for atmospheric N2O, based on a four-dimensional variational (4DVAR) technique and the atmospheric transport zoom model TM5. We focus in this study on the European domain, utilizing a comprehensive set of quasi-continuous measurements over Europe, complemented by N2O measurements from the Earth System Research Laboratory of the National Oceanic and Atmospheric Administration (NOAA/ESRL) cooperative global air sampling network. Despite ongoing measurement comparisons among networks parallel measurements at a limited number of stations show that significant offsets exist among the different laboratories. Since the spatial gradients of N2O mixing ratios are of the same order of magnitude as these biases, the direct use of these biased datasets would lead to significant errors in the derived emissions. Therefore, in order to also use measurements with unknown offsets, a new bias correction scheme has been implemented within the TM5-4DVAR inverse modelling system, thus allowing the simultaneous assimilation of observations from different networks. The N2O bias corrections determined in the TM5-4DVAR system agree within ~0.1 ppb (dry-air mole fraction) with the bias derived from the measurements at monitoring stations where parallel NOAA discrete air samples are available. The N2O emissions derived for the northwest European and east European countries for 2006 show good agreement with the bottom-up emission inventories reported to the United Nations Framework Convention on Climate Change (UNFCCC). Moreover, the inverse model can significantly narrow the uncertainty range reported in N2O emission inventories for these countries, while the lack of measurements does not allow to reduce the uncertainties of emission estimates in southern Europe. Several sensitivity experiments were performed to test the robustness of the results. It is shown that also inversions without detailed a priori spatio-temporal emission distributions are capable to reproduce major regional emission patterns within the footprint of the existing atmospheric network, demonstrating the strong constraints of the atmospheric observations on the derived emissions
    TransCom model simulations of CH4 and related species: linking transport, surface flux and chemical loss with CH4 variability in the troposphere and lower stratosphere
    Patra, P.K. ; Houweling, S. ; Krol, M.C. ; Bousquet, P. ; Belikov, D. - \ 2011
    Atmospheric Chemistry and Physics 11 (2011)24. - ISSN 1680-7316 - p. 12813 - 12837.
    general-circulation model - biomass burning emissions - atmospheric methane - growth-rate - interannual variability - methyl chloroform - tracer transport - sf6 - gases - co2
    A chemistry-transport model (CTM) intercomparison experiment (TransCom-CH4) has been designed to investigate the roles of surface emissions, transport and chemical loss in simulating the global methane distribution. Model simulations were conducted using twelve models and four model variants and results were archived for the period of 1990–2007. All but one model transports were driven by reanalysis products from 3 different meteorological agencies. The transport and removal of CH4 in six different emission scenarios were simulated, with net global emissions of 513±9 and 514±14 TgCH4 yr-1 for the 1990s and 2000s, respectively. Additionally, sulfur hexafluoride (SF6) was simulated to check the interhemispheric transport, radon (222Rn) to check the subgrid scale transport, and methyl chloroform (CH3CCl3) to check the chemical removal by the tropospheric hydroxyl radical (OH). The results are compared to monthly or annual mean time series of CH4, SF6 and CH3CCl3 measurements from 8 selected background sites, and to satellite observations of CH4 in the upper troposphere and stratosphere. Most models adequately capture the vertical gradients in the stratosphere, the average long-term trends, seasonal cycles, interannual variations (IAVs) and interhemispheric (IH) gradients at the surface sites for SF6, CH3CCl3 and CH4. The vertical gradients of all tracers between the surface and the upper troposphere are consistent within the models, revealing vertical transport differences between models. An average IH exchange time of 1.39±0.18 yr is derived from SF6 time series. Sensitivity simulations suggest that the estimated trends in exchange time, over the period of 1996–2007, are caused by a change of SF6 emissions towards the tropics. Using six sets of emission scenarios, we show that the decadal average CH4 growth rate likely reached equilibrium in the early 2000s due to the flattening of anthropogenic emission growth since the late 1990s. Up to 60% of the IAVs in the observed CH4 concentrations can be explained by accounting for the IAVs in emissions, from biomass burning and wetlands, as well as meteorology in the forward models. The modeled CH4 budget is shown to depend strongly on the troposphere-stratosphere exchange rate and thus on the model’s vertical grid structure and circulation in the lower stratosphere. The 15-model median CH4 and CH3CCl3 atmospheric lifetimes are estimated to be 9.99±0.08 and 4.61±0.13 yr, respectively, with little IAV due to transport and temperature.
    Grenzen voor luchtkwaliteit: Effecten van discontinue blootstelling aan etheen en stikstofoxiden op paprika
    Dijk, C.J. van; Meinen, E. ; Dueck, T.A. - \ 2011
    Wageningen : Wageningen UR Glastuinbouw (Rapporten GTB 1107) - 38
    rookgassen - kasgewassen - glastuinbouw - glasgroenten - concentratie - blootstelling - capsicum - componenten - schade - gassen - gewasproductie - flue gases - greenhouse crops - greenhouse horticulture - greenhouse vegetables - concentration - exposure - capsicum - components - damage - gases - crop production
    Het doseren van rookgassen met CO2 in de glastuinbouw kan grote gevolgen hebben voor het rendement van de bedrijven. Concentraties van toxische componenten kunnen sterk fluctueren in de tijd en komen zelden tot nooit alleen voor. Om het effect van deze typen blootstellingen in te kunnen schatten zijn paprikaplanten blootgesteld aan de twee belangrijkste rookgassen, NOx en etheen. De resultaten van dit onderzoek tonen aan dat blootstelling aan zowel continue als discontinue etheen concentraties van 40 ppb of hoger al na enkele dagen tot zichtbare effecten leiden. Etheen had ook een sterk negatief effect op de knoppen die tijdens de blootstellingsperiode werden gevormd; deze vielen grotendeels af waardoor ook geen bloemen en vruchten tot ontwikkeling kwamen. Dit onderzoek toont aan dat paprikaplanten minder sterk reageren op discontinue blootstellingen van etheen dan op continue, mogelijk als gevolg van het optreden van herstelmechanismen. Dit betekent dat tuinders mogelijk meer CO2 kunnen doseren dan op basis van de bestaande effectgrenswaarden voor mogelijk werd gehouden. De positieve effecten van CO2 op de gewasontwikkeling leiden nauwelijks tot vermindering van de etheengevoeligheid. Vertaald naar de praktijk betekent dit dat tuinders die CO2 doseren met rookgassen geen vermindering van de etheeneffecten hoeven te verwachten mochten de etheenconcentraties te hoog oplopen.
    Voorkomen van gewasschade door rookgassen
    Dueck, Tom - \ 2010
    loss prevention - fumes - gases - smoke - plant protection - emission - vegetable growing - agricultural research - cogeneration - greenhouse horticulture
    Rookgassen uit de WKK: betekenis voor het gewas
    Dueck, Tom - \ 2009
    greenhouse horticulture - cogeneration - energy - fumes - gases - smoke - pollution - loss prevention - greenhouse crops
    Positive feedback between global warming and atmospheric CO2 concentration inferred from past climate change
    Scheffer, M. ; Brovkin, V. ; Cox, P.M. - \ 2006
    Geophysical Research Letters 33 (2006)10. - ISSN 0094-8276 - p. 1 - 4.
    carbon-cycle - ice core - antarctic ice - temperatures - greenhouse - gases - model
    There is good evidence that higher global temperatures will promote a rise of greenhouse gas levels, implying a positive feedback which will increase the effect of anthropogenic emissions on global temperatures. However, the magnitude of this effect predicted by the available models remains highly uncertain, due to the accumulation of uncertainties in the processes thought to be involved. Here we present an alternative way of estimating the magnitude of the feedback effect based on reconstructed past changes. Linking this information with the mid-range Intergovernmental Panel on Climate Change estimation of the greenhouse gas effect on temperature we suggest that the feedback of global temperature on atmospheric CO2 will promote warming by an extra 15¿78% on a century-scale. This estimate may be conservative as we did not account for synergistic effects of likely temperature moderated increase in other greenhouse gases. Our semi-empirical approach independently supports process based simulations suggesting that feedback may cause a considerable boost in warming.
    Inverse modelling of national and European CH4 emissions using the atmospheric zoom model TM5
    Bergamaschi, P. ; Krol, M.C. ; Dentener, F. ; Vermeulen, A. ; Meinhardt, F. ; Graul, R. ; Ramonet, M. ; Peters, W. ; Dlugokencky, E.J. - \ 2005
    Atmospheric Chemistry and Physics 5 (2005)9. - ISSN 1680-7316 - p. 2431 - 2460.
    modern methane emissions - natural wetlands - co2 sources - interannual variability - transport - gases - sensitivity - lifetime - history - climate
    A synthesis inversion based on the atmospheric zoom model TM5 is used to derive top-down estimates of CH4 emissions from individual European countries for the year 2001. We employ a model zoom over Europe with 1° × 1° resolution that is two-way nested into the global model domain (with resolution of 6° × 4°. This approach ensures consistent boundary conditions for the zoom domain and thus European top-down estimates consistent with global CH4 observations. The TM5 model, driven by ECMWF analyses, simulates synoptic scale events at most European and global sites fairly well, and the use of high-frequency observations allows exploiting the information content of individual synoptic events. A detailed source attribution is presented for a comprehensive set of 56 monitoring sites, assigning the atmospheric signal to the emissions of individual European countries and larger global regions. The available observational data put significant constraints on emissions from different regions. Within Europe, in particular several Western European countries are well constrained. The inversion results suggest up to 50-90% higher anthropogenic CH4 emissions in 2001 for Germany, France and UK compared to reported UNFCCC values (EEA, 2003). A recent revision of the German inventory, however, resulted in an increase of reported CH4 emissions by 68.5% (EEA, 2004), being now in very good agreement with our top-down estimate. The top-down estimate for Finland is distinctly smaller than the a priori estimate, suggesting much smaller CH4 emissions from Finnish wetlands than derived from the bottom-up inventory. The EU-15 totals are relatively close to UNFCCC values (within 4-30%) and appear very robust for different inversion scenarios.
    Water soluble inorganic trace gases and related aerosol compounds in the tropical boundary layer. An analysis based on real time measurements at a pasture site in the Amazon Basin
    Trebs, I. - \ 2005
    Wageningen University. Promotor(en): J. Slanina. - [S.l.] : S.n. - ISBN 9789085041733 - 144
    rivierwater - aërosolen - gassen - energiebalans - atmosfeer - amazonia - brazilië - grenslaag - river water - aerosols - gases - energy balance - atmosphere - amazonia - brazil - boundary layer

    This dissertation investigates the behavior of water-soluble inorganic trace gases and related aerosol species in the tropical boundary layer. Mixing ratios of ammonia (NH3), nitric acid (HNO3), nitrous acid (HONO), hydrochloric acid (HCl), sulfur dioxide (SO;,) and the corresponding water-soluble aerosol species, ammonium (NH,,1), nitrate (NO3 ), nitrite (NO,), chloride (CI) and sulfate (SO,") were measured at a pasture site in the Amazon Basin (Rondónia, Brazil). Sampling was performed from 12 Sep. to 14 Nov. 2002, covering the late dry (biomass burning) season, the transition period and the onset of the wet season (clean conditions) (LBA-SMOCC*). Measurements were made continuously using a wet-annular denuder (WAD) in combination with a Steam-Jet Aerosol Collector (SJAC) followed by on-line analysis. Real-time data were combined with measurements of the aerosol compounds sodium (Na+), potassium (K), calcium (Ga ), magnesium (Mg2) and low-molecular weight polar organic acids determined using integrated filter samples. Additionally, on-line measured mixing ratios of nitric oxide (NO), nitrogen dioxide (NTX) and ozone (O3) as well as (microj-meteorological quantities are considered, Gaseous NH3 was present in mixing ratios an order of magnitude higher than those of HN0:i, HONO, HCl and SO,. Thermodynamic equilibrium models are used to explore the impact of mineral cations (particularly pyrogenic K+) and LMW polar organic acids on the NH4+-NO3"-C1 -SO.," -H2O aerosol system. Mineral cations present in Amazonian fine mode aerosols significantly balanced aerosol NO.," and SO/ during daytime and (NH4)2SOj appeared to be only a minor aerosol component. Thermodynamic equilibrium permitted the formation of aqueous ??,,??;, and NH^Cl only during nighttime at RH>90 %. During daytime, excess NH3 neutralized LMW polar organic acids, forming aerosol NRy. Local dry and wet deposition rates of inorganic ? are presented. Dry ? deposition was inferred using the "big leaf multiple resistance approach" and a canopy compensation point model. Dry ? deposition is dominated by NH:i and NO3, which featured highest mixing ratios as a consequence of biomass burning activities during the dry season. The pasture site was likely to have a strong potential for daytime NH3 (re-) emission, owing to high canopy compensation points, which are related to high surface temperatures and to direct NH^ emissions from cattle excreta. Total (dry + wet) ? deposition was estimated to be 7.3 - 9.8 kgN ha"1 yr"\ which exceeds predictions for the Amazon region by global chemistry and transport models by at least factor of two.
    Microgolven en plasmagas voor bestrijden zonder chemie
    Vegter, B. ; Bartels, P. - \ 2005
    Vakblad voor de Bloemisterij 60 (2005)27. - ISSN 0042-2223 - p. 38 - 39.
    tuinbouw - plantenziektebestrijding - elektromagnetische straling - microgolfstraling - gassen - stikstof - steriliseren - desinfectie - methodologie - landbouwkundig onderzoek - horticulture - plant disease control - electromagnetic radiation - microwave radiation - gases - nitrogen - sterilizing - disinfection - methodology - agricultural research
    De tuinbouwsector is niet de enige, die op zoek is naar een energiezuinige, chemicaliënvrije ziektebestrijding. In de levensmiddelentechnologie is al druk geexperimenteerd met magnetrontechniek en wordt onderzoek gedaan met nieuwkomer plasmagas. De tuinbouw kan van deze ervaringen profiteren
    Gasvormige emissies, mesttoediening en mestsamenstelling in de veehouderij : ex post evaluatierapportage van onderzoeksprogramma 309 : meten en monitoren van emissies van ammoniak, geur en broeikasgassen uit veehouderijgebouwen, ammoniakemissiemetingen bij mesttoediening in de praktijk en ontwikkeling van innovatieve methoden voor het meten van de mestsamenstelling
    Mol, G. ; Monteny, G.J. - \ 2004
    Wageningen : Agrotechnology & Food Innovations (Rapport / Agrotechnology & Food Innovations nr. 77) - ISBN 9789067547512 - 77
    emissie - gassen - ammoniak - geurstoffen - dierlijke meststoffen - samenstelling - meting - monitoring - dierhouderij - huisvesting, dieren - emission - gases - ammonia - odours - animal manures - composition - measurement - monitoring - animal husbandry - animal housing
    CA – bewaring aardbeiplanten : opschaling naar de praktijk
    Evenhuis, A. ; Schoorl, F.W. - \ 2003
    Horst Meterik, Randwijk : Praktijkonderzoek Plant & Omgeving, Sector AGV & BFP - 17
    aardbeien - koelcellen - plantmateriaal met wortels zonder kluit - gassen - houdbaarheid (kwaliteit) - kosten-batenanalyse - vegetatieve vermeerdering - strawberries - cold stores - bare rooted stock - gases - keeping quality - cost benefit analysis - vegetative propagation
    CA–bewaring is teeltkundig mogelijk, in jaren waarbij het plantmateriaal zich moeilijk laat bewaren kunnen CA - condities helpen de bewaring tot een goed einde te brengen. De meerkosten van CA - bewaring zullen bepalend zijn voor al of niet introductie in de praktijk. Deze kosten kunnen meevallen als gebruik gemaakt kan worden van bestaande ULO cellen die tijdens de bewaarperiode van aardbeiplanten niet ergens anders voor gebruikt worden. De geschatte meerkosten zijn ongeveer 1 cent per trayplant. Bij een potentiële opbrengstverhoging van 5% in het najaar worden deze terugverdiend.Aangetoond is dat grotere eenheden onder CA–condities bewaard kunnen worden.
    Alternatieve bestrijding insecten en mijten
    Conijn, C.G.M. - \ 2003
    BloembollenVisie 1 (2003)2. - ISSN 1571-5558 - p. 20 - 20.
    bloembollen - insectenplagen - acariciden - insecten - geïntegreerde bestrijding - opslag - gasbewaring - gassen - ornamental bulbs - insect pests - acaricides - insects - integrated control - storage - controlled atmosphere storage - gases
    Alternatieve bestrijding van insecten en mijten in bollen tijdens de bewaring is mogelijk middels CA-behandeling (zuurstofgehalte verlagen en/of de C0²-concentratie te verhogen). Het onderzoek is er nu op gericht om te bepalen bij welke behandelingsduur en bij welke temperatuur en luchtsamenstelling de insecten en mijten gedood worden
    Ontwerp van nieuwe meetprotocollen voor het meten van gasvormige emissies in de landbouw
    Hofschreuder, P. ; Mosquera Losada, J. ; Ogink, N.W.M. - \ 2003
    Wageningen : Agrotechnology & Food Innovations, WUR (Rapport / Agrotechnology & Food Innovations no. 008) - ISBN 9789067547277 - 94
    emissie - gassen - meting - huisvesting, dieren - ventilatie - analytische methoden - emission - gases - measurement - animal housing - ventilation - analytical methods
    Binnen het Europese onderzoeksproject Welfare Quality® werden protocollen opgesteld die het mogelijk maken om het welzijn aan het dier zélf te meten. De protocollen zijn echter lijvig, waardoor één welzijnsmeting afhankelijk van de diersoort 5 tot 8 uur vergt. Het ministerie van EL&I wil de protocollen vereenvoudigen, zodat ze gemakkelijk zijn in te zetten op veebedrijven.
    Groen gras en de Broeikas
    Hensen, A. ; Kasper, G.J. ; Pol, A. van den; Verkade, G.W. - \ 2003
    Praktijkkompas. Rundvee 17 (2003)4. - ISSN 1570-8586 - p. 24 - 25.
    graslanden - emissie - gassen - methaan - kooldioxide - stikstofoxide - rundvee - bodemeigenschappen - broeikaseffect - meting - onderzoeksprojecten - europese unie - grasslands - emission - gases - methane - carbon dioxide - nitric oxide - cattle - soil properties - greenhouse effect - measurement - research projects - european union
    Hoeveel CO2 wordt op een hectare grasland opgenomen, en hoeveel lachgas ontsnapt uit de bodem? Wat is de methaanemissie van de koeien die op die hectares grazen en hoeveel methaan komt er uit de mest die de dames achter laten? Kunnen we dat ook meten en kunnen we met metingen laten zien wat het effect is van verschillende beheersmaatregelen? Al deze vragen hebben te maken met het broeikaseffect en met de afspraken die Nederland gemaakt heeft om de emissies van broeikasgassen te beteugelen. Het Greengrass-project probeert nieuwe puzzelstukjes te vinden om het totaalplaatje van de gasuitwisseling boven graslanden in beeld te brengen.
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