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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    Food security investments - Transforming the aquaculture, dairy and horticulture sectors in Kenya : Recommendations to support the transition from aid to inclusive aid and trade
    Kessler, J.J. ; Coninx, I. ; Kilelu, C.W. ; Vugt, S.M. van; Koomen, I. ; Bebe, Bockline ; Soma, K. ; Ndambi, O.A. ; Gema, Joyce ; Obwanga, Benson ; Rurangwa, E. ; Moreno Echeverri, I.M. ; Beekman, G. ; Wangui Koge, Jessica ; Lee, Jan van der; Daburon, A.I.L. ; Wesonga, John ; Ruben, R. - \ 2020
    Wageningen Centre for Development Innovation, Wageningen University & Research (WCDI-20-123 ) - 7 p.
    Rapid and robust on-scene detection of cocaine in street samples using a handheld near-infrared spectrometer and machine learning algorithms
    Kranenburg, Ruben F. ; Verduin, Joshka ; Weesepoel, Yannick ; Alewijn, Martin ; Heerschop, Marcel ; Koomen, Ger ; Keizers, Peter ; Bakker, Frank ; Wallace, Fionn ; Esch, Annette van; Hulsbergen, Annemieke ; Asten, Arian C. van - \ 2020
    Drug Testing and Analysis 12 (2020)10. - ISSN 1942-7603 - p. 1404 - 1418.
    cocaine - forensic illicit-drug analysis - indicative testing - k-nearest neighbors - near-infrared

    On-scene drug detection is an increasingly significant challenge due to the fast-changing drug market as well as the risk of exposure to potent drug substances. Conventional colorimetric cocaine tests involve handling of the unknown material and are prone to false-positive reactions on common pharmaceuticals used as cutting agents. This study demonstrates the novel application of 740–1070 nm small-wavelength-range near-infrared (NIR) spectroscopy to confidently detect cocaine in case samples. Multistage machine learning algorithms are used to exploit the limited spectral features and predict not only the presence of cocaine but also the concentration and sample composition. A model based on more than 10,000 spectra from case samples yielded 97% true-positive and 98% true-negative results. The practical applicability is shown in more than 100 case samples not included in the model design. One of the most exciting aspects of this on-scene approach is that the model can almost instantly adapt to changes in the illicit-drug market by updating metadata with results from subsequent confirmatory laboratory analyses. These results demonstrate that advanced machine learning strategies applied on limited-range NIR spectra from economic handheld sensors can be a valuable procedure for rapid on-site detection of illicit substances by investigating officers. In addition to forensics, this interesting approach could be beneficial for screening and classification applications in the pharmaceutical, food-safety, and environmental domains.

    Drivers of Farm-level Adoption of Crop Extension Packages in Ethiopia
    Tafere, Tewodros ; Elias, Eyasu ; Koomen, I. - \ 2020
    Wageningen : Wageningen Centre for Development Innovation - 28 p.
    Smallholder farmers’ adoption of agricultural technologies varies to a great degree with respect to spatial diversity, household related characteristics, access to infrastructure and institutional design. This cross-sectional study was conducted in order to understand the factors affecting the uptake agricultural technologies in the highlands of Ethiopia. Analysis was conducted on data collected in 2014 from a survey of 2,880 households in four major regions of the country covering 30 districts. Econometric method (two-limit Tobit model) was used to analyse determinants of farm-level adoption of crop technology packages promoted by the national agricultural extension service. Findings reveal that 71%, 66%, 60%, 52%, 46% and 29% of the sample households adopted recommended technology packages for potato, wheat, maize, tef, barley, and sorghum respectively. Results demonstrate that agro-ecology and spatial variability, distance from homestead to farm plots, slope index of the farm, access to extension services, access to credit, lagged gross annual income and membership to a cooperatives were all significant factors influencing technology adoption. The study shows there is significant variation in technology adoption between model farmers and non-model farmers. However, the productivity difference is limited to few crops. The findings suggest that investment in infrastructure, promoting access to institutional services and access to credit are instrumental to technology adoption by smallholders. The extension strategy should therefore promote inclusive strategy in which both model and non-model farmers have equal access to technology supply and extension services.
    Issue Brief 4 - Impact of COVID-19 pandemic and measures on the fruit sector in Côte d’Ivoire
    Boyd, Salome ; Coulibaly, Moussa ; Groote, Bram de; Koomen, I. - \ 2020
    - 4 p.
    Issue Brief 5 - Impact of COVID-19 pandemic on the Horticulture sector in Ghana
    Groote, Bram de; Assibey-Yeboah, Sheila ; Boyd, Salome ; Koomen, I. - \ 2020
    - 4 p.
    Using the Climate Atlas as a tool to spur climate change adaptation in the Kenyan Horticulture sector : 3R Kenya Practice Brief no. 019
    Selm, Merlijn C. van; Matsaba, Emmanuel ; Coninx, I. ; Koomen, I. ; Wesonga, John M. ; Goosen, H. - \ 2020
    Wageningen Centre for Development Innovation, Wageningen University & Research (WCDI-20-119/3R Kenya Practice Brief 019) - 8 p.
    This policy brief describes how climate change may affect the Kenyan horticulture sector and what can be done to tackle climate change impacts. The main questions considered were:
    • What kind of climate change can be expected?
    • How will this impact the horticulture sector?
    • What is the potential for action?
    This brief describes how data is used to answer these questions
    Handboek leeftijdsbepalingen (versie 3.0)
    Bolle, L.J. ; Hoek, R. ; Pennock-Vos, M.G. ; Beier, Ulrika ; Dijkman Dulkes, H.J.A. ; Os-Koomen, E. van; Snaar, Beanne ; Vries, M. de; Pasterkamp, T.L. ; Koelemij, E.I. ; Beintema, J.J. ; Bakker, A.G. ; Huijer, T. ; Sneekes, A.C. ; Meeren-Pido, H. van der; Wiegerinck, J.A.M. - \ 2020
    Centrum voor Visserijonderzoek (Rapport / Centrum voor Visserijonderzoek CVO rapport 20.012) - 119 p.
    Piloting a fresh fruit and vegetables market to deliver high quality, safe food products : Reflections and lessons learned
    Gema, Joyce ; Koge, Jessica W. ; Keige, John ; Moreno-Echeverri, Indira ; Kipkoech-Kosgei, Carolyne ; Matsaba, Emmanuel ; Kilelu, Catherine ; Wesonga, John ; Koomen, Irene - \ 2020
    Wageningen : Wageningen Centre for Development Innovation (Report / Wageningen Centre for Development Innovation WCDI-20-117) - 49
    Meta-analysis of 3R Kenya findings about the transformation of the aquaculture, dairy and horticulture sectors : Recommendations to support the transition from aid to inclusive aid and trade
    Kessler, Jan Joost ; Coninx, Ingrid ; Kilelu, Catherine ; Vugt, Simone van; Koomen, Irene ; Bebe, Bockline ; Soma, Katrine ; Ndambi, Asaah ; Gema, Joyce ; Obwanga, Benson ; Rurangwa, Eugene ; Moreno Echeverri, Indira ; Beekman, Gonne ; Wangui Koge, Jessica ; Lee, Jan van der; Daburon, Annabelle ; Wesonga, John ; Ruben, Ruerd - \ 2020
    Wageningen : Wageningen Centre for Development Innovation (Report / Wageningen Centre for Development Innovation WCDI-20-116) - 63
    Vismonitoring Zoete Rijkswateren en Overgangswateren t/m 2019 : Deel II, Toegepaste methoden
    Keeken, O.A. van; Bruijn, P.J.A. de; Griffioen, A.B. ; Os-Koomen, E. van; Wiegerinck, J.A.M. - \ 2020
    IJmuiden : Wageningen Marine Research (Wageningen Marine Research rapport C047/20) - 102
    Om een inschatting te krijgen van de toestand van de zoete rijkwateren en overgangswateren worden diverse vismonitoringsprogramma’s uitgevoerd. Deze programma’s maken deel uit van het Wettelijke Onderzoekstaken (WOT) programma in opdracht van het ministerie van Landbouw, Natuur en Voedselkwaliteit (LNV) en het Programmaplan Vis-en Biotamonitoring 2018-2023 van Rijkswaterstaat (RWS). In totaal worden 13 monitoringsprogramma’s en één registratieprogramma in de grote zoete rijkswateren (meren en rivieren), de overgangswateren en de spuikom bij Kornwerderzand in de Waddenzee uitgevoerd. Ontsluiting van vismonitoringsgegevens gebeurt op drie manieren. Het voorliggende rapport (Deel II) is een achtergronddocument waarin de gebruikte monitoringsmethodieken in de verschillende vismonitoringen in de zoete rijkswateren en overgangswateren t/m 2019 worden vastgelegd. In het rapport ‘Toestand en trends’ (Deel I) worden de resultaten geïnterpreteerd (trends en duiding). Daarnaast worden de monitoringsdata via een dataportaal1 ontsloten (voorheen rapportage Deel III). Wijzigingen die in 2019 zijn doorgevoerd, staan puntsgewijs opgesomd in paragraaf 1.1. De veranderingen betreffen het beëindigen van bepaalde bemonsteringen of juist het starten van nieuwe bemonsteringen, maar ook veranderingen in monsterlocaties of –frequenties en rapportage.
    Valuing the effect of land use change on landscape services on the urban–rural fringe
    Zhou, Ting ; Kennedy, Erin ; Koomen, Eric ; Leeuwen, Eveline S. van - \ 2020
    Journal of Environmental Planning and Management 63 (2020)13. - ISSN 0964-0568 - p. 2425 - 2445.
    economic valuation - land-use change - lansdscape services - the Netherlands - urban–rural fringe

    The urban–rural fringe is a dynamic environment where urban expansion limits the provision of landscape services. Economic valuation of these services is proposed to quantify the impact of urbanisation and inform planners of the potential losses that attribute to these land-use changes. However, most evaluation methods remain controversial regarding shortcomings in providing reliable results. This study applies market price, contingent valuation and value transfer methods and compares their performance in assessing the economic impact of land-use changes on the urban–rural fringe of the Amstelland (the Netherlands). Results with these applied methods differ greatly due to their respective advantages in revealing use values or non-use values of landscape services and dependence on land-use change. Thus, results are sensitive to value types, the scarcity of landscape services, scale of the study area, and involved stakeholders. This paper reflects on the strengths and weaknesses of these methods in different planning contexts.

    Progress Report HortiFresh West Africa 2019 : Commercial Fruit & Vegetable Sector Development in West Africa programme
    Assibey-Yeboah, Sheila ; Koomen, I. - \ 2020
    Wageningen Centre for Development Innovation (WCDI-20-105 )
    This report can also be downloaded from : http://www.d-portal.org/
    3R Kenya (Robust, Reliable and Resilient) - From aid to trade project, annual report 2019
    Koge, Jessica ; Kilelu, C.W. ; Vugt, S.M. van; Coninx, I. ; Koomen, I. ; Soma, K. ; Obwanga, Benson ; Gema, Joyce ; Omedo Bebe, Bockline - \ 2020
    Wageningen Centre for Development Innovation, Wageningen University & Research (WCDI-20-104 ) - 42 p.
    Climate-resilient horticulture for sustainable county development in Kenya
    Patrick, Esther M. ; Koge, Jessica ; Zwarts, Emiel ; Wesonga, John M. ; Atela, Joanes O. ; Tonui, Charles ; Kilelu, Catherine ; Goosen, Hasse ; Coninx, Ingrid ; Koomen, Irene - \ 2020
    Wageningen : Wageningen Centre for Development Innovation (Report / Wageningen Centre for Development Innovation WCDI-20-107) - 49
    Climate change presents one of the greatest challenges to the productivity and sustainable growth of the agricultural sector in Kenya due to extreme events such as droughts and floods as well as changes in temperature. Horticultural crops are particularly sensitive to climate change because of their high water demand and strict temperature requirements. Increased or decreased rainfall and increased temperature result in drought or flooding, lack of water for irrigation, and pests and diseases epidemic can affect the suitability of areas for growing horticultural crops. Understanding the impacts of climate for a given crop under specific conditions is key to supporting further development of the horticulture sector. While horticulture is a priority economic subsector in many counties, it is not known how the counties position themselves with regard to dealing with climate change threats in the sector. A review of the literature shows how climate change significantly affects the performance of horticultural crops across a variety of climatic zones and that counties need to be better prepared to address these effects. Horticulture covers myriad crops (including fruits and vegetables), which are affected by climate change in different ways. Seasonal patterns, both for temperature as well as (onset of) rainfall are changing. Temperature thresholds for specific crops are being exceeded, while some areas are now more favourable for growing certain crops where previously temperatures were too low. Suboptimal temperatures affect both the yield and quality of produce. The horticulture sector has also experienced incidences of pests, such as Tuta absoluta on tomato; climate change is a confounding factor to the spread and establishment of these pests. Agriculture which is highly affected by climate change is devolved to counties; as such, policies relevant to it are expected to be implemented at county level. An analysis of the County Integrated Development Plans showed that horticulture is a high-value subsector that plays a major role in generating revenue for county development. Most counties have prioritized horticulture and made substantial investments. Climate change is acknowledged as a threat to different sectors, but there is only scant analysis of the factors causing it, effects it will have and proposed responses to it. Farmers and crop officers from Kiambu and Kajiado counties are aware of climate change and its effects on horticulture. However, understanding of the relationship between cause and effect and of possible mitigating actions is weak. We observed that at all levels, in the field as well as at county level, preparedness for climate change is low and government support to the farmers is also limited. Due attention and informed decision-making based on, for example the Kenya Climate Atlas that is currently being developed, is required.
    BENEFIT Partnership - 2019 annual report : Bilateral Ethiopian-Netherlands effort for food, income and trade partnership
    Alemu, Dawit ; Koomen, Irene ; Schaap, Mirjam ; Ayana, Amsalu ; Borman, Gareth ; Elias, Eyasu ; Smaling, Eric ; Getaw, Helen ; Becx, Gertjan ; Sopov, Monika ; Terefe, Geremew ; Schrader, Ted ; Tafere, Tewodros ; Vonk, Remko - \ 2020
    Wageningen : Wageningen Centre for Development Innovation (Report / Wageningen Centre for Development Innovation WCDI-20-094) - 211
    Op naar het patatje zonder
    Steingröver, Eveliene ; Koomen, Arjan - \ 2019

    het onderzoek van Eveliene Steingrover en Arjan Koomen wordt aangehaald.

    Vismonitoring Zoete Rijkswateren en Overgangswateren t/m 2018 : Deel II: Toegepaste methoden
    Sluis, M.T. van der; Cremer, J.M.S. ; Griffioen, A.B. ; Keeken, O.A. van; Os-Koomen, E. van; Wiegerinck, J.A.M. ; Bruijn, P.J.A. de - \ 2019
    IJmuiden : Wageningen Marine Research (Wageningen Marine Research rapport C086/19) - 98
    Om een inschatting te krijgen van de kwaliteit van de zoete rijkwateren en overgangswateren, wordt het vismonitoringprogramma uitgevoerd. Dit programma maakt deel uit van het Programmaplan Vis-en Biotamonitoring 2018-2023 van Rijkswaterstaat en het Wettelijke Onderzoekstaken (WOT) programma in opdracht van het ministerie van Landbouw, Natuur en Voedselkwaliteit (LNV). Het programma bestaat uit 13 monitoringsprogramma’s en één registratieprogramma in de grote zoete rijkswateren (meren en rivieren) en overgangswateren en in de spuikom bij Kornwerderzand in de Waddenzee. Ontsluiting van vismonitoringsgegevens gebeurt op drie manieren: Deel I ‘Toestand en trends’ waarin de resultaten worden geïnterpreteerd (trends en duiding), het hier voorliggende rapport (Deel II) is een achtergronddocument waarin de gebruikte monitoringsmethodieken in de verschillende vismonitoringen in de zoete rijkswateren en overgangswateren t/m 2018 worden vastgelegd. Daarnaast worden de monitoringsdata via het dataportal1 ontsloten, voorheen heette dat Deel III. Wijzigingen die in 2018 zijn doorgevoerd, staan puntsgewijs opgesomd in paragraaf 1.1. De veranderingen betreffen het beëindigen van bepaalde bemonsteringen of juist het starten van nieuwe bemonsteringen, maar ook veranderingen in monsterlocaties of –frequenties en rapportage.
    Reisverslag BTS 2019
    Boois, I.J. de; Os-Koomen, E. van - \ 2019
    IJmuiden : Centrum voor Visserijonderzoek (Rapport / Centrum voor Visserijonderzoek CVO 19.017) - 44 p.
    The History of Dutch Agricultural
    Gordijn, F. ; Koomen, I. ; Maimu, Zaina ; Zwarts, Harm ; Botden, N. - \ 2019
    Wageningen Centre for Development Innovation
    3R Kenya (Robust, Reliable and Resilient) - From aid to trade project : Annual report 2018
    Koge, Jessica ; Kilelu, Catherine ; Coninx, I. ; Vugt, S.M. van; Lee, J. van der; Koomen, I. ; Soma, K. ; Obwanga, Benson ; Gema, Joyce ; Omedo Bebe, Bockline - \ 2019
    Wageningen Centre for Development Innovation (WCDI-19-057 )
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