{"id":17118,"date":"2026-08-26T09:55:33","date_gmt":"2026-08-26T07:55:33","guid":{"rendered":"https:\/\/www.proefschriftmaken.nl\/portfolio\/marien-korevaar\/"},"modified":"2026-08-26T09:55:41","modified_gmt":"2026-08-26T07:55:41","slug":"marien-korevaar","status":"publish","type":"us_portfolio","link":"https:\/\/www.proefschriftmaken.nl\/en\/portfolio\/marien-korevaar\/","title":{"rendered":"Marien Korevaar"},"content":{"rendered":"","protected":true},"excerpt":{"rendered":"","protected":true},"author":8,"featured_media":17119,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"footnotes":""},"us_portfolio_category":[45],"class_list":["post-17118","us_portfolio","type-us_portfolio","status-publish","post-password-required","hentry","us_portfolio_category-new-template"],"acf":{"main_text":"","naam_van_het_proefschift":"Quantification of atmospheric emissions from livestock houses to the surrounding environment","samenvatting":"In de afgelopen decennia is de wereldwijde consumptie van dierlijke eiwitten aanzienlijk toegenomen, wat heeft geleid tot een uitbreiding van de veehouderij. Tegelijkertijd zijn stallen ontwikkeld tot grotere en technologisch geavanceerdere gebouwen, wat hogere regionale concentraties dieren mogelijk maakt. In veel landen is de veehouderij niet alleen ge\u00efntensiveerd, maar ook steeds meer geografisch geconcentreerd geraakt. Hoewel veehouderij positief kan bijdragen aan het verkleinen van de ecologische voetafdruk van de landbouw, kan het ook nadelige lokale milieueffecten veroorzaken. Stallen kunnen bronnen worden van luchtvervuiling, eutrofi\u00ebring en verzuring in de directe omgeving. Atmosferische emissies uit stallen waarover men zich in het bijzonder zorgen maakt zijn ammoniak, fijnstof, bio-aerosolen en geur, die nadelig bijdragen aan de omgeving.\n\nHet kwantificeren van deze emissies is essentieel voor het beoordelen van de impact van stallen op biodiversiteit en volksgezondheid in de omgeving. De methoden en strategie\u00ebn die nodig zijn voor de kwantificering van emissies hangen af van de specifieke emissiecomponenten, evenals de schaal waarop emissies worden ge\u00ebvalueerd. Dit proefschrift onderzoekt en evalueert methoden en strategie\u00ebn voor het kwantificeren van emissies uit stallen met als doel de geschiktheid van deze benaderingen voor diverse toepassingen te beoordelen.\n\nHoofdstuk 1 geeft een algemene inleiding, beginnend met een overzicht van de relevante emissiecomponenten uit stallen en de potenti\u00eble methoden voor de meting daarvan. Vervolgens worden de belangrijkste benaderingen voor het schatten van gemiddelde emissies uit stallen besproken. Op basis van dit overzicht worden de belangrijkste uitdagingen binnen dit onderzoeksdomein ge\u00efdentificeerd, die de basis vormen voor de doelstellingen van dit proefschrift.\n\nDe algemene doelstelling van dit proefschrift is het bieden van passende kennis en hulpmiddelen voor de kwantificering van atmosferische emissies uit stallen naar de omgeving. De uitdaging met betrekking tot de kwantificering is onderverdeeld in drie kernaspecten: de nauwkeurigheid van meetmethoden, de schaal van emissievariabiliteit en het ontwerp van meetstrategie\u00ebn. Dit proefschrift richt zich op deze aspecten met een focus op de emissie van PM10 en ammoniak uit stallen in de intensieve veehouderij. Dit komt neer op drie specifieke doelstellingen:\n1. evalueer de nauwkeurigheid van de referentiemethode voor het meten van PM10 in stallen vergeleken met de Europese referentiemethode voor buitenlucht en het effect van diercategorie\u00ebn op de nauwkeurigheid van deze methode.\n2. krijg inzicht in de (bronnen van) variabiliteit van ammoniak- en PM10-emissie binnen en tussen stallen.\n3. ontwerp en beoordeel meetstrategie\u00ebn om gemiddelde ammoniak- en PM10-emissies over verschillende tijdsbestekken te schatten.\n\nOm deze doelen te bereiken is in hoofdstuk 2 en 3 onderzoek gedaan naar de nauwkeurigheid van de gravimetrische referentiemethode voor PM10 in stallen. Er is gevonden dat, onder stalcondities, de cycloon als pre-separator nauwkeuriger is dan de impactor. In representatieve stallen bleek de relatie tussen metingen met de impactor en met de cycloon afhankelijk te zijn van de diercategorie. Hoofdstuk 3 concludeert dat verschillen in deeltjesgrootteverdeling (PSD) tussen diercategorie\u00ebn groot genoeg zijn om consistent verschillen in de relatie tussen impactor en cycloon te veroorzaken.\n\nGebruikmakend van de gravimetrische referentiemethode onderzocht hoofdstuk 4 hoe continue meting van PM10-concentraties mogelijk zou kunnen maken in pluimveestallen. Deze studie bevestigde dat lichtverstrooiingstechnieken PM10-concentraties in voli\u00e8rehuisvesting met relatief hoge nauwkeurigheid kunnen meten, mits er intermitterende meetstrategie\u00ebn worden toegepast om sensoroverbelasting te voorkomen. Hoofdstuk 5 onderzocht meetstrategie\u00ebn voor het schatten van gemiddelde NH3-emissies uit vleesvarkensstallen. Het bleek dat het gelijkmatig verdelen van metingen over het jaar de laagste onzekerheid opleverde. De nauwkeurigheid kan verder worden verbeterd door metingen te standaardiseren op basis van productiecyclus en buitentemperatuur.\n\nMeetstrategie\u00ebn en variatie in fijnstofemissies werden in hoofdstuk 6 onderzocht voor een breed scala aan diercategorie\u00ebn op 74 bedrijven. Dit maakte het mogelijk representatieve gemiddelde PM10-emissies vast te stellen. Bij vleeskuikens wordt 74% van de variatie verklaard door gewicht en buitentemperatuur, terwijl bij vleesvarkens het gewicht en de relatieve luchtvochtigheid binnen 52% van de variatie verklaren.\n\nHet afsluitende hoofdstuk 7 biedt een synthese van de conclusies. Onzekerheden in meetmethoden en -strategie\u00ebn hebben direct invloed op de schatting van de impact op volksgezondheid en biodiversiteit. Inzicht in emissieniveaus en verschillen tussen stallen is cruciaal voor het identificeren van kansen voor emissiereductie, maar vereist integratie met inzichten in productiviteit en dierenwelzijn.","summary":"Over recent decades, global consumption of animal-based protein has increased substantially, driving an expansion of livestock farming. Concurrently, livestock houses have developed towards larger and more technologically advanced houses, enabling higher regional concentrations of animals. In many countries, livestock production has not only intensified but has also become increasingly geographically concentrated. While livestock farming can potentially contribute positively to reducing the environmental footprint of agriculture, livestock farming can also generate disadvantageous local environmental effects. Livestock houses may become sources of air pollution, eutrophication and acidification in the surrounding environment. Atmospheric emissions originating from livestock houses particularly of concern are ammonia, particulate matter, bio-aerosols, and odor contributing adversely to the surrounding environment.\n\nQuantifying these emissions is essential for assessing the impacts of livestock housing on biodiversity and public health in the surrounding environment. The methods and strategies required for emission quantification depend on the specific emission components under consideration, as well as on the scale for which emissions are evaluated. This thesis investigates and evaluates methods and strategies for quantifying emissions from livestock houses with the aim of evaluating the suitability of these approaches for diverse applications.\n\nChapter 1 provides a general introduction, beginning with an overview of the relevant emission components from livestock houses and the potential methods for their measurement. Subsequently, the main approaches used to estimate average emissions from livestock houses are reviewed. Based on this overview, the key challenges within this research domain are identified, forming the basis for the objectives of this thesis.\n\nThe overall objective of this thesis is to provide appropriate knowledge and tools for the quantification of atmospheric emissions from livestock houses to the surrounding environment. The challenge related to the quantification of atmospheric emission is broken down to three key aspects: accuracy of measurement methods, the scale of emission variability and design of measurement strategies. This thesis aims at addressing these key aspects with a focus on the emission of PM10 and ammonia from livestock houses in intensive farming. This comes down to three specific objectives for this thesis:\n1. evaluate the accuracy of the reference method for measuring PM10 in livestock houses compared to the European reference method for ambient air and the effect of livestock categories on the accuracy of this method.\n2. gain insight in the (sources of) variability of ammonia and PM10 emission within and among livestock houses.\n3. design and assess measurement strategies to estimate average ammonia and PM10 emissions over different timeframes.\n\nTo address these aims, in Chapters 2 and 3, research is conducted on the accuracy of the gravimetric reference method for PM10 in livestock houses, since understanding the reference method is essential for studying measurement strategies and variation in emissions. It is found that, under livestock housing conditions, the cyclone as a pre-separator of the sampler is more accurate than the impactor, which is applied in ambient air as the European reference method. In experiments carried out in representative livestock houses for the livestock categories fattening pigs, laying hens and broilers, the relationship between measurements with the impactor and with the cyclone as a pre-separator was shown to depend on the livestock category. These findings were consistently found in the meta-analysis presented in Chapter 2.\n\nAs a possible explanation for the difference in the relationship between cyclone and impactor measurements across livestock categories, Chapter 3 investigated the effect of particle size distribution (PSD). It is concluded that the differences in PSD between livestock categories are sufficiently large to consistently cause differences in the relationship between impactor and cyclone. These findings support the findings of Chapter 2 that livestock category specific calibration functions are recommended for accurate PM10 measurements in livestock houses. However, since the differences in impactor\/cyclone relationships among livestock categories identified in the sensitivity analysis in Chapter 3 are significantly smaller than those reported in empirical studies in Chapter 2, it is not likely that PSD is the sole predictor of the impactor\/cyclone relationship in livestock houses.\n\nUsing the gravimetric reference method for PM10, Chapter 4 investigated how an alternative method could enable continuous measurement of PM10 concentrations under the challenging conditions of poultry houses. This study confirmed that the use of a light scattering technique makes it possible to measure PM10 concentrations in cage free laying hen houses with relatively high accuracy, but after a certain period is subject to malfunctioning due to PM overloading of the sensor. Besides, this study showed that a high extent of autocorrelation appears in PM10 concentration levels in cage-free poultry houses over time, which indicates that intermittent measurement strategies can be applied. Based on the observed variability and insights from literature on the relation-ship between PM10 generation and hen behavior and housing management, different measurement strategies were developed. Application of found strategies allows instruments to be used for longer periods without maintenance, keeping the uncertainty of the monitoring limited, and enabling the determination of PM10 concentrations on an hourly, daily, and long-term basis.\n\nChapter 5 also examined measurement strategies, but in this case to estimate average NH3 emissions from livestock houses. Based on continuous measurements of actual ammonia emissions from twelve conventional fattening pig houses, annual averages were determined for each house, as well as the variation over time. Using these data series, it was possible to test different measurement strategies for their accuracy. These strategies consisted of continuously monitoring during a certain period of the year to estimate the mean, conducting measurements on a few days distributed throughout the year or measuring on several days distributed over the year and production cycles. Using the extensive data series obtained from a substantial number of conventional fattening pig houses, the strategies could be compared, showing that equally distributing measurements over the year yields the lowest uncertainty for estimating mean NH3 emissions from a single fattening pig house. The average uncertainty across twelve houses was lowest for strategies distributing measurements over the year and production cycles. The study further demonstrates that accuracy can be improved by standardizing measurements based on independent relationships between NH3 emissions, production cycle stage and outdoor temperature. Depending on the monitoring objective, continuous measurement on consecutive days for a certain part of the year may nevertheless represent a practical strategy.\n\nMeasurement strategies and variation within and between livestock houses were also investigated for particulate matter emissions in Chapter 6, in this case across a much wider range of livestock categories. Using the calibration functions established in Chapter 2, PM10 emission measurements were analyzed from 24 h measurements conducted at 74 farms, covering 15 housing systems for poultry, pigs, dairy goats and dairy cows. This analysis allowed to establish representative average PM10 emissions for the livestock categories and housing systems included in the study. Other findings provided valuable insights into the variation of PM10 emissions. PM10 emissions in broilers are strongly correlated with broiler weight and outdoor temperature, explaining 74% of the variation, whereas for fattening pigs, pig weight and indoor relative humidity explain 52% of the variation. Combined with the insight in variation within and among livestock houses for different livestock categories this can contribute to more effective measurement strategies and improved emission modeling.\n\nThe final Chapter 7 provides a synthesis of the main conclusions of this thesis and discusses the findings of Chapters 2 through 6, examining them from two perspectives. In this discussion, the challenge of assessing atmospheric emissions from livestock houses to the surrounding environment is considered from outside and inside the farm. From the environmental perspective, the dispersion of emission components to nearby residents or sensitive ecosystems is of primary concern. Uncertainties in measurement methods and strategies directly affect the estimation of potential impacts on public health and biodiversity, implying that not all measurement approaches are equally suitable for all applications. From the livestock housing perspective, understanding emission levels is linked to the conditions and processes in the livestock house driving the formation of emission components. Insight into emission levels and differences between livestock houses can be valuable for identifying opportunities for emission reduction; however, emission information alone does not provide actionable guidance unless it is accompanied by insight into their implications for productivity, animal welfare, and other emission components.","auteur":"Marien Korevaar","auteur_slug":"marien-korevaar","publicatiedatum":"21 september 2026","taal":"EN","url_flipbook":"https:\/\/ebook.proefschriftmaken.nl\/ebook\/marienkorevaar?iframe=true","url_download_pdf":"https:\/\/ebook.proefschriftmaken.nl\/download\/479b0b4c-c037-4321-9b1a-567ef48ff2e3\/highres","url_epub":"","ordernummer":"19264","isbn":"","doi_nummer":"","naam_universiteit":"Wageningen University","afbeeldingen":17120,"video_url":"","podcast_url":"","naam_student:":"","binnenwerk":"","universiteit":"Wageningen University","cover":"","afwerking":"","cover_afwerking":"","design":""},"_links":{"self":[{"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/us_portfolio\/17118","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/us_portfolio"}],"about":[{"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/types\/us_portfolio"}],"author":[{"embeddable":true,"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/comments?post=17118"}],"version-history":[{"count":1,"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/us_portfolio\/17118\/revisions"}],"predecessor-version":[{"id":17121,"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/us_portfolio\/17118\/revisions\/17121"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/media\/17119"}],"wp:attachment":[{"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/media?parent=17118"}],"wp:term":[{"taxonomy":"us_portfolio_category","embeddable":true,"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/us_portfolio_category?post=17118"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}