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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    Influence of educational actions on transitioning of food safety culture in a food service context: Part 1 – Triangulation and data interpretation of food safety culture elements
    Mariano Zanin, Lais ; Luning, P.A. ; Cunha, Diogo Thimoteo da; Stedefeldt, Elke - \ 2021
    Elsevier 119 (2021). - 12 p.
    Foodborne diseases still occur globally, and alongside food safety systems, food safety culture has been established as a factor in ensuring food safety. This study describes the development of a mixed-methods approach to collecting quantitative and qualitative data and interpreting the triangulated data to assess the prevailing food safety culture. The mixed-methods approach was designed based on the literature and was tested in a food service establishment at an army headquarters in Brazil. Both managers (3) and food handlers (39) participated. The quantitative (questionnaires and checklists) and qualitative (participant observations) data were triangulated using a scoring system on an interpretation grid. The scoring system typified the prevailing food safety culture (FS-culture) and its elements as reactive (score 1), reactive to active (score 1–2), active (score 2), active to proactive (score 2–3), or proactive (score 3) FS-culture. The overall prevailing FS-culture in the case study, scored 1–2. This FS-culture score was mainly attributed to the score 1 for the elements of leadership, risk perception, and management systems, styles and processes, and the score 1–2 for communication, knowledge, and work environment. The mixed-methods approach revealed an overestimation of FS-culture elements in the quantitative analysis and underestimation in the qualitative analysis. This discrepancy in results emphasises the usefulness of the concurrent analysis and highlights the need to employ triangulation to enable a comprehensive assessment of the prevailing FS-culture. The assessment provides concrete input for the development of educational actions aiming for changes in the prevailing FS-culture.
    Influence of educational actions on transitioning of food safety culture in a food service context: Part 2 - Effectiveness of educational actions in a longitudinal study
    Mariano Zanin, Lais ; Stedefeldt, Elke ; Silva, Sueli Maria da; Cunha, Diogo Thimoteo da; Luning, P.A. - \ 2021
    Food Control 120 (2021). - ISSN 0956-7135 - 11 p.
    Recently, the food safety culture (FS-culture) gained attention as a critical factor for reducing foodborne diseases. This study investigated the effectiveness of educational actions in the transition of FS-culture in a longitudinal study using action research in an army food service, which was selected as a case. We hypothesised that the FS-culture assessment might be a good starting point to develop educational actions. First, we identified the educational needs of food handlers and managers based on a FS-culture assessment, followed by the implementation of educational actions using three formats (tutored, planned, and with the managers). A previously developed mixed-method approach was used for the collection of qualitative and quantitative data, data triangulation, and an interpretation grid that was used for categorisation into reactive, active, or proactive FS-culture. The triangulated data showed that the prevailing FS-culture changed from reactive to more proactive during the longitudinal study. The educational actions changed attitudes, practices, personal relationships, and the work environment. The educational actions were effective in influencing the prevailing FS-culture and confirmed the research hypothesis. Furthermore, the mixed-method approach with the interpretation grid was useful in assessing the transition in the prevailing FS-culture. Further research may test the usefulness of other types of food services in other countries. We also recommend converting the scientific methods for FS-culture assessment into methods suitable for the use by food safety managers in food services.
    MagnetGrid : Model description and user guide
    Diogo, Vasco ; Hennen, Wil ; Verma, Monika ; Oudendag, Diti ; Kuiper, Marijke - \ 2020
    Wageningen : Wageningen Economic Research (Wageningen Economic Research report 2020-004) - 65
    MagnetGrid is een modulair economisch landgebruiksmodel dat ruimtelijk expliciete biofysische informatie combineert met macro-economische projecties. MagnetGrid visualiseert toekomstige agrarisch landgebruikspatronen gedreven door een combinatie van klimatologische en socioeconomische ontwikkelingen. Het model kwantificeert de impact van deze trends en de mogelijke uitruil tussen verschillende doelstellingen. De ruimtelijk expliciete analyses van MagnetGrid kunnen voor een breed publiek toegankelijk gemaakt worden door kaarten die veranderingen in landgebruik laten zien op wereld-, regio-, land- en lokaal niveau.
    The role of local energy initiatives in co-producing sustainable places
    Soares da Silva, Diogo ; Horlings, Lummina G. - \ 2020
    Sustainability Science 15 (2020). - ISSN 1862-4065 - p. 363 - 377.
    Citizen initiatives - Co-production - Energy transition - Governance - Local energy initiatives - Sustainable place shaping

    During the first two decades of the twenty-first century, the introduction of policies that promote renewable energy in Western European countries facilitated a shift towards the production of cleaner energy and its decentralisation. Subsidies, incentive schemes, and declining installation costs—combined with rapid technology advances—made the investment in small-scale solar photovoltaic (PV) panels and wind turbines more attractive for individuals and small businesses. Simultaneously, we observe the emergence of citizen initiatives which aim to provide public services across various sectors, including renewable energy generation and distribution. These initiatives, started by citizens, often involve the participation of local residents and prioritise social and environmental goals. In some areas, governments and engaged citizens work together to achieve common goals through citizen–government co-production. In this article, we address the question: how can the co-production of government(s) and citizens, through local energy initiatives, contribute to the shaping of more sustainable places? Using the PlaCI model—a conceptual model of citizen initiatives and their role in shaping sustainable places—we conduct an analysis of WindpowerNijmegen, a citizen-led renewable energy cooperative in the Netherlands. We assess who the relevant stakeholders are, what are the enabling conditions for fruitful collaboration, which new arrangements are established, and how they contribute to shaping more sustainable places. The results indicate that local energy initiatives are place based, conditioned by the characteristics of the physical space needed for the production of renewable energy, specific institutional arrangements, place-based assets and people’s capacities characteristic for the place, and past collaboration.

    Comparing cities of the world according to their food security risks and opportunities
    Hennen, Wil ; Diogo, Vasco ; Polman, Nico ; Dijkshoorn-Dekker, Marijke - \ 2018
    In: Sustainable Development and Planning X. - WIT Press (WIT Transactions on Ecology and the Environment ) - ISBN 9781784662912 - p. 953 - 962.
    Due to the combined effect of climate change, expected population growth and increased concentration of population in cities and towns, food insecurity in urban areas is becoming of increasing concern and is regarded as one of the most prominent development challenges for the 21st century. Cities differ with respect to their specific food security risks and opportunities of local food supply to meet the increasing demand for food. The tool “Global Metropolitan Detector” has been developed to compare cities of the world based on different dimensions of food security, particularly availability, accessibility, and affordability of food, risk of floods and climate change, and healthy diets. Worldwide publicly available datasets, e.g. from FAOSTAT, EarthStat and WorldClim, are used. These are separately converted (aggregated/disaggregated) to a homogenous 5 arc-minute grid and combined in the tool to calculate (by weighted average) and compare the demand and local supply of food, including the required area of land to meet the city-specific consumption needs (measured in “Food Metres”). The purpose is to benchmark 850 cities based on several aspects related to food security. The resulting benchmark of cities and their indicator values can be visualised in maps showing their position with respect to food security in general, or investigate particular aspects in more detail, e.g. cities having low/high flood risks or cities that are better able to meet the demand of (fresh) vegetables and fruit from local producers. The maps can support policymakers to identify causes and locations of food insecurity, and the indicative results – based on limited available worldwide data – can serve as an inducement for further investigation with more detailed data from cities.
    Instrumentarium Kosten Natuurbeleid 2018 - Status A : IKN versie 3.0
    Michels, R. ; Diogo, V. ; Hennen, W.H.G.J. ; Puister, L.F. - \ 2018
    Wageningen : Wettelijke Onderzoekstaken Natuur & Milieu (WOt-technical report 134) - 145
    The Cost of Nature Policies Tool (IKN) calculates the annual costs of the national ecological network under various scenarios. The tool is modularly constructed and in essence consists of several cost tables and a computational model. The purpose of the current report is to consolidate the model documentation and provide a quality assurance assessment. It contains a theoretical framework, a technical description of the computational model and cost tables, and a description of the operation of the model and of the data used. The quality of the calculations was evaluated by means of validation, verification, and sensitivity and uncertainty analyses of the model.
    Citizen initiatives in the post-welfare state
    Silva, Diogo Soares da; Horlings, Lummina G. ; Figueiredo, Elisabete - \ 2018
    Social Sciences 7 (2018)12. - ISSN 2076-0760
    Citizen initiatives - Citizen-led initiatives - Co-production - Sustainable place-shaping

    Recently we have seen the emergence of citizen-led community initiatives and civic enterprises, taking over governmental tasks in providing public services in various sectors, such as energy, care, landscape maintenance, and culture. This phenomenon can be explained by a renewed interest in community, place, and 'local identity'; the erosion of the welfare state; the privatization of public services; a re-emergence of the social economy; and tensions between 'bottom-up' initiatives and the changing role of the state. The co-production of governments and initiatives can potentially result in a shift from government-led to community-led planning. This, however, raises questions about their innovative potential, the democratic consequences, and the potential roles of governments in enabling these societal dynamics. This article discusses these issues theoretically, illustrated with empirical examples from Portugal, the Netherlands, and Wales, in a context of uncertainty regarding the future of the traditional European welfare state.

    Phylogenetic classification of the world's tropical forests
    Slik, J.W.F. ; Franklin, Janet ; Arroyo-Rodríguez, Víctor ; Field, Richard ; Aguilar, Salomon ; Aguirre, Nikolay ; Ahumada, Jorge ; Aiba, Shin Ichiro ; Alves, Luciana F. ; Anitha, K. ; Avella, Andres ; Mora, Francisco ; Aymard, Gerardo A.C. ; Báez, Selene ; Balvanera, Patricia ; Bastian, Meredith L. ; Bastin, Jean François ; Bellingham, Peter J. ; Berg, Eduardo Van Den; Conceição Bispo, Polyanna Da; Boeckx, Pascal ; Boehning-Gaese, Katrin ; Bongers, Frans ; Boyle, Brad ; Brambach, Fabian ; Brearley, Francis Q. ; Brown, Sandra ; Chai, Shauna Lee ; Chazdon, Robin L. ; Chen, Shengbin ; Chhang, Phourin ; Chuyong, George ; Ewango, Corneille ; Coronado, Indiana M. ; Cristóbal-Azkarate, Jurgi ; Culmsee, Heike ; Damas, Kipiro ; Dattaraja, H.S. ; Davidar, Priya ; DeWalt, Saara J. ; Din, Hazimah ; Drake, Donald R. ; Duque, Alvaro ; Durigan, Giselda ; Eichhorn, Karl ; Eler, Eduardo Schmidt ; Enoki, Tsutomu ; Ensslin, Andreas ; Fandohan, Adandé Belarmain ; Farwig, Nina ; Feeley, Kenneth J. ; Fischer, Markus ; Forshed, Olle ; Garcia, Queila Souza ; Garkoti, Satish Chandra ; Gillespie, Thomas W. ; Gillet, Jean Francois ; Gonmadje, Christelle ; Granzow-De La Cerda, Iñigo ; Griffith, Daniel M. ; Grogan, James ; Hakeem, Khalid Rehman ; Harris, David J. ; Harrison, Rhett D. ; Hector, Andy ; Hemp, Andreas ; Homeier, Jürgen ; Hussain, M.S. ; Ibarra-Manríquez, Guillermo ; Hanum, I.F. ; Imai, Nobuo ; Jansen, Patrick A. ; Joly, Carlos Alfredo ; Joseph, Shijo ; Kartawinata, Kuswata ; Kearsley, Elizabeth ; Kelly, Daniel L. ; Kessler, Michael ; Killeen, Timothy J. ; Kooyman, Robert M. ; Laumonier, Yves ; Laurance, Susan G. ; Laurance, William F. ; Lawes, Michael J. ; Letcher, Susan G. ; Lindsell, Jeremy ; Lovett, Jon ; Lozada, Jose ; Lu, Xinghui ; Lykke, Anne Mette ; Mahmud, Khairil Bin; Mahayani, Ni Putu Diana ; Mansor, Asyraf ; Marshall, Andrew R. ; Martin, Emanuel H. ; Matos, Darley Calderado Leal ; Meave, Jorge A. ; Melo, Felipe P.L. ; Mendoza, Zhofre Huberto Aguirre ; Metali, Faizah ; Medjibe, Vincent P. ; Metzger, Jean Paul ; Metzker, Thiago ; Mohandass, D. ; Munguía-Rosas, Miguel A. ; Muñoz, Rodrigo ; Nurtjahy, Eddy ; Oliveira, Eddie Lenza De; Onrizal, ; Parolin, Pia ; Parren, Marc ; Parthasarathy, N. ; Paudel, Ekananda ; Perez, Rolando ; Pérez-García, Eduardo A. ; Pommer, Ulf ; Poorter, Lourens ; Qi, Lan ; Piedade, Maria Teresa F. ; Pinto, José Roberto Rodrigues ; Poulsen, Axel Dalberg ; Poulsen, John R. ; Powers, Jennifer S. ; Prasad, Rama Chandra ; Puyravaud, Jean Philippe ; Rangel, Orlando ; Reitsma, Jan ; Rocha, Diogo S.B. ; Rolim, Samir ; Rovero, Francesco ; Rozak, Andes ; Ruokolainen, Kalle ; Rutishauser, Ervan ; Rutten, Gemma ; Mohd Said, Mohd Nizam ; Saiter, Felipe Z. ; Saner, Philippe ; Santos, Braulio ; Santos, João Roberto Dos; Sarker, Swapan Kumar ; Schmitt, Christine B. ; Schoengart, Jochen ; Schulze, Mark ; Sheil, Douglas ; Sist, Plinio ; Souza, Alexandre F. ; Spironello, Wilson Roberto ; Sposito, Tereza ; Steinmetz, Robert ; Stevart, Tariq ; Suganuma, Marcio Seiji ; Sukri, Rahayu ; Sultana, Aisha ; Sukumar, Raman ; Sunderland, Terry ; Supriyadi, S. ; Suresh, H.S. ; Suzuki, Eizi ; Tabarelli, Marcelo ; Tang, Jianwei ; Tanner, Ed V.J. ; Targhetta, Natalia ; Theilade, Ida ; Thomas, Duncan ; Timberlake, Jonathan ; Morisson Valeriano, Márcio De; Valkenburg, Johan Van; Do, Tran Van; Sam, Hoang Van; Vandermeer, John H. ; Verbeeck, Hans ; Vetaas, Ole Reidar ; Adekunle, Victor ; Vieira, Simone A. ; Webb, Campbell O. ; Webb, Edward L. ; Whitfeld, Timothy ; Wich, Serge ; Williams, John ; Wiser, Susan ; Wittmann, Florian ; Yang, Xiaobo ; Yao, C.Y.A. ; Yap, Sandra L. ; Zahawi, Rakan A. ; Zakaria, Rahmad ; Zang, Runguo - \ 2018
    Proceedings of the National Academy of Sciences of the United States of America 115 (2018)8. - ISSN 0027-8424 - p. 1837 - 1842.
    Biogeographic legacies - Forest classification - Forest functional similarity - Phylogenetic community distance - Tropical forests

    Knowledge about the biogeographic affinities of the world's tropical forests helps to better understand regional differences in forest structure, diversity, composition, and dynamics. Such understanding will enable anticipation of region-specific responses to global environmental change. Modern phylogenies, in combination with broad coverage of species inventory data, now allow for global biogeographic analyses that take species evolutionary distance into account. Here we present a classification of the world's tropical forests based on their phylogenetic similarity. We identify five principal floristic regions and their floristic relationships: (i) Indo-Pacific, (ii) Subtropical, (iii) African, (iv) American, and (v) Dry forests. Our results do not support the traditional neo- versus paleotropical forest division but instead separate the combined American and African forests from their Indo-Pacific counterparts. We also find indications for the existence of a global dry forest region, with representatives in America, Africa, Madagascar, and India. Additionally, a northern-hemisphere Subtropical forest region was identified with representatives in Asia and America, providing support for a link between Asian and American northernhemisphere forests.

    Recreational sea fishing in Europe in a global context-Participation rates, fishing effort, expenditure, and implications for monitoring and assessment
    Hyder, Kieran ; Weltersbach, Marc Simon ; Armstrong, Mike ; Ferter, Keno ; Townhill, Bryony ; Ahvonen, Anssi ; Arlinghaus, Robert ; Baikov, Andrei ; Bellanger, Manuel ; Birzaks, Janis ; Borch, Trude ; Cambie, Giulia ; Graaf, Martin De; Diogo, Hugo M.C. ; Dziemian, Łukasz ; Gordoa, Ana ; Grzebielec, Ryszard ; Hartill, Bruce ; Kagervall, Anders ; Kapiris, Kostas ; Karlsson, Martin ; Kleiven, Alf Ring ; Lejk, Adam M. ; Levrel, Harold ; Lovell, Sabrina ; Lyle, Jeremy ; Moilanen, Pentti ; Monkman, Graham ; Morales-Nin, Beatriz ; Mugerza, Estanis ; Martinez, Roi ; O'Reilly, Paul ; Olesen, Hans Jakob ; Papadopoulos, Anastasios ; Pita, Pablo ; Radford, Zachary ; Radtke, Krzysztof ; Roche, William ; Rocklin, Delphine ; Ruiz, Jon ; Scougal, Callum ; Silvestri, Roberto ; Skov, Christian ; Steinback, Scott ; Sundelöf, Andreas ; Svagzdys, Arvydas ; Turnbull, David ; Hammen, Tessa van der; Voorhees, David Van; Winsen, Frankwin Van; Verleye, Thomas ; Veiga, Pedro ; Vølstad, Jon-Helge ; Zarauz, Lucia ; Zolubas, Tomas ; Strehlow, Harry V. - \ 2018
    Fish and Fisheries 19 (2018)2. - ISSN 1467-2960 - p. 225 - 243.
    European marine recreational fisheries - fisheries assessment and management - fishing effort and expenditure - participation - surveys and monitoring of marine recreational fisheries
    Marine recreational fishing (MRF) is a high-participation activity with large economic value and social benefits globally, and it impacts on some fish stocks. Although reporting MRF catches is a European Union legislative requirement, estimates are only available for some countries. Here, data on numbers of fishers, participation rates, days fished, expenditures, and catches of two widely targeted species were synthesized to provide European estimates of MRF and placed in the global context. Uncertainty assessment was not possible due to incomplete knowledge of error distributions; instead, a semi-quantitative bias assessment was made. There were an estimated 8.7 million European recreational sea fishers corresponding to a participation rate of 1.6%. An estimated 77.6 million days were fished, and expenditure was €5.9 billion annually. There were higher participation, numbers of fishers, days fished and expenditure in the Atlantic than the Mediterranean, but the Mediterranean estimates were generally less robust. Comparisons with other regions showed that European MRF participation rates and expenditure were in the mid-range, with higher participation in Oceania and the United States, higher expenditure in the United States, and lower participation and expenditure in South America and Africa. For both northern European sea bass (Dicentrarchus labrax, Moronidae) and western Baltic cod (Gadus morhua, Gadidae) stocks, MRF represented 27% of the total removals. This study highlights the importance of MRF and the need for bespoke, regular and statistically sound data collection to underpin European fisheries management. Solutions are proposed for future MRF data collection in Europe and other regions to support sustainable fisheries management.
    Stakeholders’ perspectives on the operationalisation of the ecosystem service concept: Results from 27 case studies
    Dick, Jan ; Turkelboom, Francis ; Woods, Helen ; Iniesta-Arandia, Irene ; Primmer, Eeva ; Saarela, Sanna-Riikka ; Bezák, Peter ; Mederly, Peter ; Leone, Michael ; Verheyden, Wim ; Kelemen, Eszter ; Hauck, Jennifer ; Andrews, Chris ; Antunes, Paula ; Aszalós, Réka ; Baró, Francesc ; Barton, David N. ; Berry, Pam ; Bugter, Rob ; Carvalho, Laurence ; Czúcz, Bálint ; Dunford, Rob ; Garcia Blanco, Gemma ; Geamănă, Nicoleta ; Giucă, Relu ; Grizzetti, Bruna ; Izakovičová, Zita ; Kertész, Miklós ; Kopperoinen, Leena ; Langemeyer, Johannes ; Montenegro Lapola, David ; Liquete, Camino ; Luque, Sandra ; Martínez Pastur, Guillermo ; Martin-Lopez, Berta ; Mukhopadhyay, Raktima ; Niemela, Jari ; Odee, David ; Peri, Pablo Luis ; Pinho, Patricia ; Patrício-Roberto, Gleiciani Bürger ; Preda, Elena ; Priess, Joerg ; Röckmann, Christine ; Santos, Rui ; Silaghi, Diana ; Smith, Ron ; Vădineanu, Angheluţă ; Wal, Jan Tjalling van der; Arany, Ildikó ; Badea, Ovidiu ; Bela, Györgyi ; Boros, Emil ; Bucur, Magdalena ; Blumentrath, Stefan ; Calvache, Marta ; Carmen, Esther ; Clemente, Pedro ; Fernandes, João ; Ferraz, Diogo ; Fongar, Claudia ; García-Llorente, Marina ; Gómez-Baggethun, Erik ; Gundersen, Vegard ; Haavardsholm, Oscar ; Kalóczkai, Ágnes ; Khalalwe, Thalma ; Kiss, Gabriella ; Köhler, Berit ; Lazányi, Orsolya ; Lellei-Kovács, Eszter ; Lichungu, Rael ; Lindhjem, Henrik ; Magare, Charles ; Mustajoki, Jyri ; Ndege, Charles ; Nowell, Megan ; Nuss Girona, Sergi ; Ochieng, John ; Often, Anders ; Palomo, Ignacio ; Pataki, György ; Reinvang, Rasmus ; Rusch, Graciela ; Saarikoski, Heli ; Smith, Alison ; Soy Massoni, Emma ; Stange, Erik ; Vågnes Traaholt, Nora ; Vári, Ágnes ; Verweij, Peter ; Vikström, Suvi ; Yli-Pelkonen, Vesa ; Zulian, Grazia - \ 2018
    Ecosystem Services 29 (2018)pt. C. - ISSN 2212-0416 - p. 552 - 565.
    The ecosystem service (ES) concept is becoming mainstream in policy and planning, but operational influence on practice is seldom reported. Here, we report the practitioners’ perspectives on the practical implementation of the ES concept in 27 case studies. A standardised anonymous survey (n = 246), was used, focusing on the science-practice interaction process, perceived impact and expected use of the case study assessments. Operationalisation of the concept was shown to achieve a gradual change in practices: 13% of the case studies reported a change in action (e.g. management or policy change), and a further 40% anticipated that a change would result from the work. To a large extent the impact was attributed to a well conducted science-practice interaction process (>70%). The main reported advantages of the concept included: increased concept awareness and communication; enhanced participation and collaboration; production of comprehensive science-based knowledge; and production of spatially referenced knowledge for input to planning (91% indicated they had acquired new knowledge). The limitations were mostly case-specific and centred on methodology, data, and challenges with result implementation. The survey highlighted the crucial role of communication, participation and collaboration across different stakeholders, to implement the ES concept and enhance the democratisation of nature and landscape planning.
    Botryococcus braunii for the production of hydrocarbons and exopolysaccharides and the role of associated bacteria
    Gouveai, João Diogo Guimarães - \ 2017
    Wageningen University. Promotor(en): R.H. Wijffels, co-promotor(en): M.J. Barbosa; D. Sipkema. - Wageningen : Wageningen University - ISBN 9789463436960 - 157
    biomass production - algae - algae culture - hydrocarbons - bacteria - biomassa productie - algen - algenteelt - koolwaterstoffen - bacteriën

    Microalgae are photosynthetic organisms that are found worldwide in many different aquatic environments and therefore display an immense biological diversity. They are a promising source of many useful polymers that have industrial applications such as food, fuel, material and pharmaceutical. One microalga that has gathered quite a research community is Botryococcus braunii. The reason for its scientific club is the fact it can synthetize long chain hydrocarbons molecules from C20 to C40. These hydrocarbons have been found in oil-shales and tests show that it can be used as aviation fuel. Besides producing hydrocarbons, some strains of B. braunii can produce exopolysaccharides (EPS) composed mainly of galactose and a small fraction of fucose. The EPS has interesting rheological properties for the food industry and potential active compounds that could be used in the pharmaceutical industry .

    Like many other microorganisms, microalgae in the natural environment are usually in the presence of bacteria. The presence of bacteria with microalgae can either have a beneficial or an antagonistic effect. For B. braunii little is known about the bacteria community present especially for the EPS producing strain. For that reason, the aim of this thesis was to investigate B. braunii’s associated bacteria with the aim of improving B. braunii’s biomass growth and hydrocarbon and EPS content. In chapter one, we introduced the topic of microalgae as a potential source of sustainable polymers and we introduced the species B. braunii, describing its characteristics and scientific interest. It is also introduced the topic of microalgae and bacteria associations by looking at other studies from literature.

    In chapter two, 16 publically available strains of B. braunii were ordered in culture banks and screened for biomass productivity, hydrocarbon and total carbohydrate content. The aim of the study was to identify one or more good strains that displayed high biomass productivity as well as hydrocarbon or total carbohydrate content. In seven strains out of 16 cultivated in 250 mL volume Erlenmeyer flaks, we detected 5 to 42 % content of hydrocarbons of the dry biomass with four strains producing botryococcenes (C30-C34) and three strains producing alkanes (C20-C25). Two strains showed high amounts of EPS content above 50 % per dry biomass. Seven strains comprising of the strains with higher biomass productivity plus the highest hydrocarbons and EPS content, were tested for scalability using bench scale 800 mL volume bubble column reactors. Two strains, AC761 which produces botryococcenes and CCALA778 which produces EPS, were selected as the most promising B. braunii strains for industrial production of hydrocarbon and EPS.

    In chapter three, we studied the bacterial community associated with B. braunii. We cultured 12 strains from the initial 16 from chapter 2 and extracted the DNA from samples taken over a time period of 12 days. It was clear from this study that B. braunii hosts a variety of bacterial species and still maintain its growth. The bacteria families Rhizobiaceae, Bradyrhizobiaceae and Comamonadaceae were found in all 12 strains. These families which belong to the phylum Proteobacteria could have an important role regarding B. braunii growth. Each strain displayed a different bacterial community composition but all the strains from the CAEN culture collection clustered near each other suggesting that the algae culture collection could have an influence on the bacterial community composition. Bacteria genus identification based on 16S rRNA gene amplicon similarity showed several genera present including Rhizobium spp. and Variovorax spp.. Two genera were found that are possibly linked to hydrocarbon degradation: Sphingomonas spp. and Rhodobacter spp..

    In chapter four, we investigated further B. braunii CCALA778 which was shown in chapter 2 to accumulate high amounts of EPS. We investigated the effects of antibiotics on algal growth, EPS accumulation and bacterial community composition of CCALA778. Taxonomical identification by 16S rRNA gene analysis indicated that most of the bacteria present with CCALA778 were Gram-negative. Of all antibiotics and antibiotic mixes, only the treatment with Penicillin did not affect the growth of B. braunii. The remaining antibiotics halted the growth of CCALA778 while they were active. The exceptions were with the antibiotics Chloramphenicol, Gentamycin and Linezolid which permanently ceased the growth of CCALA778. The accumulation of EPS seemed to be related to biomass growth, but we did also observe a reduction of EPS with the cultures treated with Penicillin suggesting that bacteria could have an effect on the EPS content. Antibiotics had specific effects on the bacterial community with all treatments showing significant changes over time. The most efficient treatment in removing bacteria were the mixes Metronidazole-Rifampicin-Penicillin and Penicillin-Rifampicin which were the only treatments to show significant changes in the bacterial community when compared to the untreated cultures after 10 days of cultivation. Antibiotics and antibiotic mixes can create changes in the bacterial community but it is unlikely that they alone can lead to axenic B. braunii cultures.

    In chapter five, we used Ultra Violet-C light (UVC) to reduce bacteria diversity and abundance present in B. braunii CCALA778. UVC is highly effective in inactivating bacteria and for that reason is being investigated further in medicinal applications. After applying the UVC to B. braunii CCALA778, we were able to reduce the relative abundance of 16S rRNA genes assigned to bacteria to less than 1 % compared to the 70% in the non-treated cultures. With the UVC treated CCALA778 we observed several physiological changes. The UV treated cultures with reduced bacterial load showed nearly double the EPS accumulation when compared to the untreated. To confirm that we did not see an artefact in our results due to the UVC treatment, UVC treated cultures were also inoculated with bacteria from the untreated and we observed a reduction of EPS similar to what we saw with the untreated cultures. There were no changes to the EPS composition after the removal of the bacteria. Other physiological changes were observed, namely that colony size of B. braunii CCALA778 significantly increased when compared to the untreated culture and the UV treated with bacteria. We hypothesise that the increase in colony size was probably due to the fact there was more EPS accumulated which helped with cell aggregation. We also observed an increase on the biomass growth in the UV-treated CCALA778 which we hypothesized being related to the fact that there was none or hardly any competition for essential micronutrients such as phosphate. From this study we concluded that the associated bacteria present with B. braunii CCALA778 were antagonistic. We believe the reason why the bacteria were antagonistic is because of the readily available EPS which is a rich source of organic compounds that bacteria could use for their own proliferation allowing them to compete with B. braunii for essential nutrients.

    In chapter 6, we discuss the implications from our previous 4 experimental chapters. The aim of the study was to improve the biomass productivity and hydrocarbon and EPS content of the microalgae B. braunii. In brief, B. braunii displayed a wide range of physiological traits regarding biomass productivity and hydrocarbon and total carbohydrate content. We showed that B. braunii can co-habit with a wide range of bacteria diversity and abundance and that the associated bacteria were antagonistic to CCALA778 by affecting its biomass growth. We also showed that by removing the associated bacteria we can increase the EPS accumulation. Currently most of the research on microalgae and bacteria interactions, focus on the positive side, but we must understand also how bacteria can be antagonistic to microalga growth. Bacteria can be antagonistic to microalgae by competing for nutrients and also being detrimental to industrial process by degrading the product of interest in the case of organic carbons such as EPS. Therefore it is unlikely we can use the benefits that bacteria can provide such as enhancing growth to improve the cultivation of B. braunii and other similar microalgae species that secrete EPS. Since bacteria can be antagonistic to microalgae that secrete large amounts of organic compounds such as EPS, it is imperative to minimize contamination in large scale photobioreactors (PBR). It is important because in large scale PBR, contamination can occur leading to downtime of the reactors. If microalgae industry is to advance, it must develop PBR units that prevent contamination of bacteria from the surrounding environment.

    Assessing local and regional economic impacts of climatic extremes and feasibility of adaptation measures in Dutch arable farming systems
    Diogo, V. ; Reidsma, P. ; Schaap, B. ; Andree, B.P.J. ; Koomen, E. - \ 2017
    Agricultural Systems 157 (2017). - ISSN 0308-521X - p. 216 - 229.
    Adaptation - Arable farming - Climate change - Extreme weather events - Impact assessment - Spatial analysis
    We propose a method that combines local productivity factors, economic factors, crop-specific sensitivity to climatic extremes, and future climate change scenarios, to assess potential impacts of extreme weather events on agricultural production systems. Our assessment is spatially explicit and uses discounted time series of cash flows taking into account expected future impacts on yield and crop quality, to estimate changes in the expected net present value (NPV) of agricultural systems. We assess the economic feasibility of a portfolio of adaptation measures by considering their initial investments, annual costs, and effectiveness in reducing crop damage. We apply the method to investigate potential economic impacts of extreme weather events in arable farming systems in the Netherlands around 2050. We find that the expected increase in extreme weather events frequency can severely affect future productivity potential. Particularly, heat waves, warm winters, and high intensity rainfall are expected to substantially undermine the future economic viability of Dutch arable farming systems. The results indicate considerable differences between regions in terms of vulnerability to climatic extremes: while some regions are severely impacted by all climatic extremes, other regions consistently demonstrate high resilience to increases in extreme event frequency. The findings are robust to a wide range of scenarios and suggest that the interactions between economic factors and management practices (particularly, crop specialisation) are decisive drivers of the economic viability of agricultural systems under more frequent climatic extremes. However, the exact magnitude of the impacts remains highly uncertain, as we do not consider endogenous interactions in market conditions resulting from climate change and socio-economic developments. Nevertheless, crop adaptation measures should be regarded as no-regret strategies, since they alleviate both economic impacts and uncertainty around impact magnitude. The proposed method provides insights in region-specific threats and opportunities that are relevant for stakeholders and policy-makers. This information improves communication on main climate risks at the local and regional levels and contributes to prioritising adaptation strategies.
    Assessing the role of farm-level adaptation in limiting the local economic impacts of more frequent extreme weather events in Dutch arable farming systems
    Diogo, V. ; Reidsma, P. ; Schaap, B.F. ; Koomen, E. - \ 2017
    In: Book of abstracts. - - p. 63 - 63.
    The expected increase in extreme events frequency is likely to considerably affect future crop productivity. Appropriate adaptation measures in agricultural systems should be identified according to the main climate risks expected in a region and taking into account the role of decisions made at the farm level. Yet, there is limited understanding of the interplay between local production capabilities, regional climatic changes and more general socio-economic
    conditions. We propose a method that combines local productivity factors, economic factors, crop-specific sensitivity to climatic extremes, and climate change scenarios, to assess future economic impacts of extreme events on agricultural systems. Our assessment is spatially explicit and uses discounted time series of cash flows taking into account expected impacts on yield and
    crop quality, to estimate changes in the expected net present value of agricultural systems. We also assess the economic feasibility of a portfolio of adaptation measures by considering their initial investments, annual costs, and effectiveness in reducing crop damage. We apply the method to investigate potential economic impacts of extreme events in arable farming systems
    in the Netherlands in period around 2050. We find that the expected increase in frequency can substantially undermine the economic viability of Dutch arable farming systems. The results indicate considerable differences among regions: some regions are severely impacted by all extremes, while others consistently demonstrate high resilience. Though the exact magnitude of the impacts remains highly uncertain, adaptation measures should nevertheless be regarded as no-regret strategies, since they alleviate both economic impacts and uncertainty around impact magnitude.
    Who is consuming the countryside? An activity-based segmentation analysis of the domestic rural tourism market in Portugal
    Eusébio, Celeste ; Carneiro, Maria João ; Kastenholz, Elisabeth ; Figueiredo, Elisabete ; Soares da Silva, Diogo - \ 2017
    Journal of Hospitality and Tourism Management 31 (2017). - ISSN 1447-6770 - p. 197 - 210.
    Activity-based segmentation - Consumption - Countryside - Portugal - Rural tourism
    As a result of a well-debated set of transformations, rural areas are increasingly perceived as consumption rather than productive places, mainly associated to leisure and tourism. This paper aims to analyse the heterogeneity of domestic tourism consumption of rural areas. Based on a cluster analysis derived from a sample of the Portuguese population (N = 866) four clusters based on activities carried out in Portuguese rural areas were obtained – The Active Visitors, The Passive Nature Observers, The Inactives and The Summer Family Vacationers. These clusters of domestic market show diversity in the ways rural areas are perceived and consumed. They also differ regarding familiarity with rural areas, travel behaviour and sociodemographic profile. Results reveal the importance of offering different rural tourism products to these groups, thereby improving rural destination management and marketing.
    Dalende bodems, stijgende kosten : mogelijke maatregelen tegen veenbodemdaling in het landelijk en stedelijk gebied: beleidsstudie
    Born, G.J. van den; Kragt, F. ; Henkens, D. ; Rijken, B. ; Bemmel, B. van; Sluis, S. van der; Polman, N. ; Bos, Ernst Jenno ; Kuhlman, Tom ; Kwakernaak, C. ; Akker, J. van den; Diogo, V. ; Koomen, E. ; Lange, G. de; Bakel, J. van; Brinke, W.B.M. ten - \ 2016
    Den Haag : Planbureau voor de Leefomgeving (PBL-publicatie 1064) - 92
    Het doel van deze studie is om bodemdaling, de gevolgen van bodemdaling en het effect van mogelijke maatregelen in de Nederlandse laagveengebieden op een transparante manier in beeld te brengen. Dat doen we voor zowel het landelijk als stedelijk gebied. Deze studie laat de handelingsopties voor bestuurders zien voor afgewogen keuzes in het landelijk en stedelijk gebied ten aanzien van dilemma’s in de laagveengebieden die nu al op hun bord liggen of mogelijk in de toekomst zullen gaan spelen. Daarvoor kijken we naar een breed scala van effecten van bodemdaling, zoals de effecten op de landbouw en voedselproductie, het waterbeheer, het klimaat (CO2-emissie), natuur en landschap, en de bebouwde omgeving inclusief de infrastructuur. We geven een beeld van de orde van grootte van de problemen die door bodemdaling worden veroorzaakt en geven inzicht in de kosten en baten van bodemdaling. We kijken daarbij naar de gevolgen voor natuur, klimaat, landbouw, (water)beheer, wonen en infrastructuur.
    Climate seasonality limits leaf carbon assimilation and wood productivity in tropical forests
    Wagner, Fabien H. ; Hérault, Bruno ; Bonal, Damien ; Stahl, Clément ; Anderson, Liana O. ; Baker, Timothy R. ; Becker, Gabriel Sebastian ; Beeckman, Hans ; Boanerges Souza, Danilo ; Botosso, Paulo Cesar ; Bowman, David M.J.S. ; Bräuning, Achim ; Brede, Benjamin ; Brown, Foster Irving ; Camarero, Jesus Julio ; Camargo, Plínio Barbosa ; Cardoso, Fernanda C.G. ; Carvalho, Fabrício Alvim ; Castro, Wendeson ; Chagas, Rubens Koloski ; Chave, Jérome ; Chidumayo, Emmanuel N. ; Clark, Deborah A. ; Costa, Flavia Regina Capellotto ; Couralet, Camille ; Silva Mauricio, Paulo Henrique Da; Dalitz, Helmut ; Castro, Vinicius Resende De; Freitas Milani, Jaçanan Eloisa De; Oliveira, Edilson Consuelo De; Souza Arruda, Luciano De; Devineau, Jean-Louis ; Drew, David M. ; Dünisch, Oliver ; Durigan, Giselda ; Elifuraha, Elisha ; Fedele, Marcio ; Ferreira Fedele, Ligia ; Figueiredo Filho, Afonso ; Finger, César Augusto Guimarães ; Franco, Augusto César ; Freitas Júnior, João Lima ; Galvão, Franklin ; Gebrekirstos, Aster ; Gliniars, Robert ; Lima De Alencastro Graça, Paulo Maurício ; Griffiths, Anthony D. ; Grogan, James ; Guan, Kaiyu ; Homeier, Jürgen ; Kanieski, Maria Raquel ; Kho, Lip Khoon ; Koenig, Jennifer ; Kohler, Sintia Valerio ; Krepkowski, Julia ; Lemos-filho, José Pires ; Lieberman, Diana ; Lieberman, Milton Eugene ; Lisi, Claudio Sergio ; Longhi Santos, Tomaz ; López Ayala, José Luis ; Maeda, Eduardo Eijji ; Malhi, Yadvinder ; Maria, Vivian R.B. ; Marques, Marcia C.M. ; Marques, Renato ; Maza Chamba, Hector ; Mbwambo, Lawrence ; Melgaço, Karina Liana Lisboa ; Mendivelso, Hooz Angela ; Murphy, Brett P. ; O'Brien, Joseph J. ; Oberbauer, Steven F. ; Okada, Naoki ; Pélissier, Raphaël ; Prior, Lynda D. ; Roig, Fidel Alejandro ; Ross, Michael ; Rossatto, Davi Rodrigo ; Rossi, Vivien ; Rowland, Lucy ; Rutishauser, Ervan ; Santana, Hellen ; Schulze, Mark ; Selhorst, Diogo ; Silva, Williamar Rodrigues ; Silveira, Marcos ; Spannl, Susanne ; Swaine, Michael D. ; Toledo, José Julio ; Toledo, Marcos Miranda ; Toledo, Marisol ; Toma, Takeshi ; Tomazello Filho, Mario ; Valdez Hernández, Juan Ignacio ; Verbesselt, Jan ; Vieira, Simone Aparecida ; Vincent, Grégoire ; Volkmer De Castilho, Carolina ; Volland, Franziska ; Worbes, Martin ; Zanon, Magda Lea Bolzan ; Aragão, Luiz E.O.C. - \ 2016
    Biogeosciences 13 (2016)8. - ISSN 1726-4170 - p. 2537 - 2562.
    The seasonal climate drivers of the carbon cycle in tropical forests remain poorly known, although these forests account for more carbon assimilation and storage than any other terrestrial ecosystem. Based on a unique combination of seasonal pan-tropical data sets from 89 experimental sites (68 include aboveground wood productivity measurements and 35 litter productivity measurements), their associated canopy photosynthetic capacity (enhanced vegetation index, EVI) and climate, we ask how carbon assimilation and aboveground allocation are related to climate seasonality in tropical forests and how they interact in the seasonal carbon cycle. We found that canopy photosynthetic capacity seasonality responds positively to precipitation when rainfall is  < 2000 mm yr−1 (water-limited forests) and to radiation otherwise (light-limited forests). On the other hand, independent of climate limitations, wood productivity and litterfall are driven by seasonal variation in precipitation and evapotranspiration, respectively. Consequently, light-limited forests present an asynchronism between canopy photosynthetic capacity and wood productivity. First-order control by precipitation likely indicates a decrease in tropical forest productivity in a drier climate in water-limited forest, and in current light-limited forest with future rainfall  < 2000 mm yr−1.
    An economic theory-based explanatory model of agricultural land-use patterns : The Netherlands as a case study
    Diogo, V. ; Koomen, E. ; Kuhlman, T. - \ 2015
    Agricultural Systems 139 (2015). - ISSN 0308-521X - p. 1 - 16.
    Land-use modelling - Model validation - Net present value - Utility maximisation

    An economic theory-based land-use modelling framework is presented aiming to explain the causal link between economic decisions and resulting spatial patterns of agricultural land use. The framework assumes that farmers pursue utility maximisation in agricultural production systems, while considering alternative production options and making land-use decisions. Local utility is assumed to depend on a complex combination of different types of factors that together set the opportunities and constraints for different production options. The framework's ability to reproduce the current patterns is demonstrated for a case study in the Netherlands. The framework was implemented in a land-use modelling simulation tool rooted in economic theory, that was first specified according to the current trends in the driving forces assumed to steer land-use change. Alternative model specifications accounting for different sets of cash flows were implemented in order to explore the importance of uncertainties on model conceptualisation and structure. The allocation of agricultural land use was then simulated according to these specifications and the results were validated by comparing the simulated land-use patterns with observed ones. When cash flows accounting for path-dependency and land-use inertia were considered, the framework performed well in reproducing current patterns in the Netherlands, with a degree of correspondence of 82.2% in the pixel-by-pixel validation, up to 87.4% in the multiple resolution validation. Production costs and gross revenues seem to only partly explain the observed patterns, as shown by the lower degrees of correspondence (57.5% up to 65.0%) for the model specification solely accounting for these cash flows. In our case study, transportation costs did not seem to play a significant role in the allocation of agricultural land use, although that might be attributed to the relatively small size of the study area and the existence of a high-quality transport network. The model did not perform equally well for different production systems: land-uses specified at the crop level appeared to be particularly well allocated; those defined at the aggregated production system level performed poorer. The ability to link economic decision-making processes with the resulting agricultural land-use patterns, while incorporating complex interactions with different type of factors, implies that a coherent modelling approach for the simulation of future patterns of agriculture land use was established. This approach can be used to help policy-makers explore possible future socio-economic and environmental impacts resulting e.g. from climate change and/or policy reform, allowing them to devise strategies to cope with future challenges in agricultural systems.

    Analysing climate change impacts on local economic performance of Dutch agricultural systems
    Diogo, V. ; Reidsma, P. ; Schaap, B.F. ; Koomen, E. - \ 2014
    V. Diogo, P. Reidsma, B. Schaap, E. Koomen (2014). Analysing climate change impacts on local economic performance of Dutch agricultural systems. Poster P093: Presented at the International Conference: Deltas in Times of Climate Change II, 24-26 September, Rotterdam, the Netherlands.
    Understanding the spatial distribution of agricultural land use in view of climate-driven hydrological changes - Expert Pool Report
    Diogo, V. ; Koomen, E. ; Witte, F. ; Schaap, B.F. - \ 2013
    Utrecht : Knowledge for Climate - 13
    klimaatverandering - regionale planning - landgebruiksplanning - landbouw - gewasopbrengst - grondwaterstand - climatic change - regional planning - land use planning - agriculture - crop yield - groundwater level
    In the context of Knowledge for Climate programme, an expert pool was requested from Theme 6 (high quality climate projections) to provide data and information to study the future impacts of climate change on the agricultural land-use patterns in the Netherlands. More specifically, a number of questions were posed in regard to: 1) representing and explaining the spatial distribution of different types of farming; and 2) simulating with Land Use Scanner the future developments of agricultural land-use while taking into account effects of climate change and changes in (agricultural) policy. The main findings are summarized in the present report.
    Exploring the potential of reed as a bioenergy crop in the Netherlands
    Kuhlman, T. ; Diogo, V. ; Koomen, E. - \ 2013
    Biomass and Bioenergy 55 (2013). - ISSN 0961-9534 - p. 41 - 52.
    klimaatverandering - gewassen - landgebruik - phragmites - voedergewassen - modellen - climatic change - crops - land use - phragmites - fodder crops - models - land-use - phragmites-australis - biomass production - scenarios - biofuels - future - energy - scale - level
    Second-generation biofuels that produce biomass for combustion or ethanol production do not yet appear to be a viable alternative to agriculture as they are low-value products. This may change, however, when energy prices increase and their production is combined with the provision of other services. The current analysis explores the potential for the production of an often overlooked biomass feedstock that can be combined with water and nature management objectives: reed. This crop has the additional advantage that it can be grown under conditions that are unfavourable to most other crops. An economics-based land-use modelling approach is applied to simulate the local competition between reed and grassland used for dairy farming under four different future scenarios in the Netherlands. Based on a location-specific assessment of potential costs and benefits of these crops under scenario-based conditions this analysis shows that the cultivation of reed for bioenergy, in combination with providing additional land-use functions, while not viable option under current economic and political conditions, may become competitive within the next twenty years if any of the following developments occur: energy prices increase substantially; water tables rise in the low-lying western parts of the country due to climate change; a policy is implemented that increases bioenergy prices; or a policy is implemented that stimulates water buffering and the preservation of peat soils
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