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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    Transdisciplinary innovation in irrigated smallholder agriculture in africa
    Froebrich, Jochen ; Ludi, Eva ; Bouarfa, Sami ; Rollin, Dominique ; Jovanovic, Nebo ; Roble, Maria ; Ajmi, Tarek ; Albasha, Rami ; Bah, Sékou ; Bahri, Haithem ; Barberá, Gonzalo ; Beek, Christy van; Cheviron, Bruno ; Chishala, Benson ; Clercq, Willem de; Coulibaly, Yacouba ; Dicko, Mohammed ; Diawara, Bandiougou ; Dolinska, Aleksandra ; Ducrot, Raphaëlle ; Erkossa, Teklu ; Famba, Sebastiao ; Fissahaye, Degol ; Miguel Garcia, Angel De; Habtu, Solomon ; Hanafi, Salia ; Harper, Julia ; Heesmans, Hanneke ; Jamin, Jean Yves ; van't Klooster, Kees ; Mason, Nathaniel ; Mailhol, Jean Claude ; Marlet, Serge ; Mekki, Insaf ; Musvoto, Constansia ; Mosello, Beatrice ; Mweetwa, Alice ; Oates, Naomi ; Phiri, Elijah ; Pradeleix, Ludivine ; Querner, Erik ; Rozanov, Andrei ; Ker Rault, Philippe ; Rougier, Jean Emmanuel ; Shepande, Chizumba ; Sánchez Reparaz, Maite ; Tangara, Bréhima ; Vente, Joris De; Witt, Marlene de; Xueliang, Cai ; Zairi, Abdelaziz - \ 2020
    Irrigation and Drainage 69 (2020)S1. - ISSN 1531-0353 - p. 6 - 22.
    participatory innovation - smallholder farming, irrigation - transdisciplinary approach

    Boosting the productivity of smallholder farming systems continues to be a major need in Africa. Challenges relating to how to improve irrigation are multi-factor and multisectoral, and they involve a broad range of actors who must interact to reach decisions collectively. We provide a systematic reflection on findings from the research project EAU4Food, which adopted a transdisciplinary approach to irrigation for food security research in five case studies in Ethiopia, Mali, Mozambique, South Africa and Tunisia. The EAU4Food experiences emphasize that actual innovation at irrigated smallholder farm level remains limited without sufficient improvement of the enabling environment and taking note of the wider political economy environment. Most project partners felt at the end of the project that the transdisciplinary approach has indeed enriched the research process by providing different and multiple insights from actors outside the academic field. Local capacity to facilitate transdisciplinary research and engagement with practitioners was developed and could support the continuation and scaling up of the approach. Future projects may benefit from a longer time frame to allow for deeper exchange of lessons learned among different stakeholders and a dedicated effort to analyse possible improvements of the enabling environment from the beginning of the research process.

    Shifts in national land use and food production in Great Britain after a climate tipping point
    Ritchie, Paul D.L. ; Smith, Greg S. ; Davis, Katrina J. ; Fezzi, Carlo ; Halleck-Vega, Solmaria ; Harper, Anna B. ; Boulton, Chris A. ; Binner, Amy R. ; Day, Brett H. ; Gallego-Sala, Angela V. ; Mecking, Jennifer V. ; Sitch, Stephen A. ; Lenton, Timothy M. ; Bateman, Ian J. - \ 2020
    Nature Food 1 (2020)1. - ISSN 2662-1355 - p. 76 - 83.
    Climate change is expected to impact agricultural land use. Steadily accumulating changes in temperature and water availability can alter the relative profitability of different farming activities and promote land-use changes. There is also potential for high-impact ‘climate tipping points’, where abrupt, nonlinear change in climate occurs, such as the potential collapse of the Atlantic Meridional Overturning Circulation (AMOC). Here, using data from Great Britain, we develop a methodology to analyse the impacts of a climate tipping point on land use and economic outcomes for agriculture. We show that economic and land-use impacts of such a tipping point are likely to include widespread cessation of arable farming with losses of agricultural output that are an order of magnitude larger than the impacts of climate change without an AMOC collapse. The agricultural effects of AMOC collapse could be ameliorated by technological adaptations such as widespread irrigation, but the amount of water required and the costs appear to be prohibitive in this instance.
    Large changes in Great Britain's vegetation and agricultural land-use predicted under unmitigated climate change
    Ritchie, P.D.L. ; Harper, Anna B. ; Smith, G.S. ; Kahana, R. ; Kendon, Elizabeth J. ; Lewis, Huw ; Fezzi, Carlo ; Halleck Vega, Sol Maria ; Boulton, C.A. ; Bateman, I.J. ; Lenton, T.M. - \ 2019
    Environmental Research Letters 14 (2019). - ISSN 1748-9326
    vegetation productivity - GB - arable production - unmitigated climate change - RCP8.5
    The impact of climate change on vegetation including agricultural production has been the focus of many studies. Climate change is expected to have heterogeneous effects across locations globally, and the diversity of land uses characterising Great Britain (GB) presents a unique opportunity to testmethods for assessing climate change effects and impacts. GB is a relatively cool and damp country, hence, the warmer and generally drier growing season conditions projected for the future are expected to increase arable production. Here we use state-of-the-art, kilometre-scale climate change scenarios to drive a land surface model (JULES; Joint UK Land Environment Simulator) and anECOnometricAGricultural land use model (ECO-AG). Under unmitigated climate change, by the end of the century, the growing season in GB is projected to get>5 °C warmer and 140 mm drier on average. Rising levels of atmospheric CO2 are predicted to counteract the generally negative impacts of climate change on vegetation productivity in JULES. Given sufficient precipitation, warming favours higher value arable production over grassland agriculture, causing a predicted westward expansion of arable farming in ECO-AG. However, drying in the East and Southeast, without any CO2 fertilisation effect, is severe enough to cause a predicted reversion from arable to grassland farming. Irrigation, if implemented, could maintain this land in arable production. However, the predicted irrigation demand of ∼200 mm (per growing season) in many locations is comparable to annual predicted runoff, potentially demanding large-scale redistribution of water between seasons and/or across the country. The strength of the CO2 fertilisation effect emerges as a crucial uncertainty in projecting the impact of climate change on GB vegetation, especially farming land-use decisions.
    Measuring the impact of Verticillium longisporum on oilseed rape (Brassica napus) yield in field trials in the United Kingdom
    Depotter, J.R.L. ; Thomma, B.P.H.J. ; Wood, T.A. - \ 2019
    European Journal of Plant Pathology 153 (2019)1. - ISSN 0929-1873 - p. 321 - 326.
    Disease development - Oil content - Verticillium stem striping - Yield loss

    Verticillium longisporum causes Verticillium stem striping on oilseed rape, which appears towards the end of the cropping season. Thus far, the impact of V. longisporum infection on oilseed yield remains unclear. In this study, we assessed the impact of Verticillium stem striping on British oilseed rape production. To this end, four cultivars (Incentive, Vision, Harper and Quartz) were grown in field plots with different levels of V. longisporum disease pressure at different locations over two consecutive years. Whereas Incentive and Vision developed relatively few stem striping symptoms, Harper and especially Quartz showed severe symptoms during these field experiments. Furthermore, higher inoculum levels induced more severe symptoms in these cultivars. Significant yield reductions upon V. longisporum infection only occurred in a single field trial on all tested oilseed rape cultivars. These preliminary data suggest that Verticillium stem striping does not consistently impact oilseed rape yield, despite the occurrence of abundant disease symptoms.

    Tundra Trait Team : A database of plant traits spanning the tundra biome
    Bjorkman, Anne D. ; Myers-Smith, Isla H. ; Elmendorf, Sarah C. ; Normand, Signe ; Thomas, Haydn J.D. ; Alatalo, Juha M. ; Alexander, Heather ; Anadon-Rosell, Alba ; Angers-Blondin, Sandra ; Bai, Yang ; Baruah, Gaurav ; Beest, Mariska te; Berner, Logan ; Björk, Robert G. ; Blok, Daan ; Bruelheide, Helge ; Buchwal, Agata ; Buras, Allan ; Carbognani, Michele ; Christie, Katherine ; Collier, Laura S. ; Cooper, Elisabeth J. ; Cornelissen, J.H.C. ; Dickinson, Katharine J.M. ; Dullinger, Stefan ; Elberling, Bo ; Eskelinen, Anu ; Forbes, Bruce C. ; Frei, Esther R. ; Iturrate-Garcia, Maitane ; Good, Megan K. ; Grau, Oriol ; Green, Peter ; Greve, Michelle ; Grogan, Paul ; Haider, Sylvia ; Hájek, Tomáš ; Hallinger, Martin ; Happonen, Konsta ; Harper, Karen A. ; Heijmans, Monique M.P.D. ; Henry, Gregory H.R. ; Hermanutz, Luise ; Hewitt, Rebecca E. ; Hollister, Robert D. ; Hudson, James ; Hülber, Karl ; Iversen, Colleen M. ; Jaroszynska, Francesca ; Jiménez-Alfaro, Borja - \ 2018
    Global Ecology and Biogeography 27 (2018)12. - ISSN 1466-822X - p. 1402 - 1411.
    alpine - Arctic - plant functional traits - tundra

    Motivation: The Tundra Trait Team (TTT) database includes field-based measurements of key traits related to plant form and function at multiple sites across the tundra biome. This dataset can be used to address theoretical questions about plant strategy and trade-offs, trait–environment relationships and environmental filtering, and trait variation across spatial scales, to validate satellite data, and to inform Earth system model parameters. Main types of variable contained: The database contains 91,970 measurements of 18 plant traits. The most frequently measured traits (> 1,000 observations each) include plant height, leaf area, specific leaf area, leaf fresh and dry mass, leaf dry matter content, leaf nitrogen, carbon and phosphorus content, leaf C:N and N:P, seed mass, and stem specific density. Spatial location and grain: Measurements were collected in tundra habitats in both the Northern and Southern Hemispheres, including Arctic sites in Alaska, Canada, Greenland, Fennoscandia and Siberia, alpine sites in the European Alps, Colorado Rockies, Caucasus, Ural Mountains, Pyrenees, Australian Alps, and Central Otago Mountains (New Zealand), and sub-Antarctic Marion Island. More than 99% of observations are georeferenced. Time period and grain: All data were collected between 1964 and 2018. A small number of sites have repeated trait measurements at two or more time periods. Major taxa and level of measurement: Trait measurements were made on 978 terrestrial vascular plant species growing in tundra habitats. Most observations are on individuals (86%), while the remainder represent plot or site means or maximums per species. Software format: csv file and GitHub repository with data cleaning scripts in R; contribution to TRY plant trait database (www.try-db.org) to be included in the next version release.

    Climate-Forest-Water-People Relations: : Seven System Delineations
    Noordwijk, M. van; Creed, Irena F. ; Jones, Julia A. ; Wei, Xiaohua ; Gush, Mark ; Blanco, Juan A. ; Sullivan, Caroline A. ; Bishop, Kevin ; Murdiyarso, Daniel ; Xu, Jianchu ; Claassen, Marius ; McNulty, Steven ; Bruijnzeel, L.A. ; Harper, Richard J. ; Mwangi, Hosea ; Hacket-Pain, Andrew ; Orland, Chloé - \ 2018
    In: Forest and Water on a Changing Planet: Vulnerability, Adaptation and Governance Opportunities / Creed, Irena F., van Noordwijk, Meine, International Union of Forest Research Organizations (IUFRO) (IUFRO World Series ) - ISBN 9783902762955 - p. 27 - 58.
    Determinants of the Forest-Water Relationship
    McNulty, Steven ; Archer, E. ; Gush, Mark ; Noordwijk, M. van; Ellison, David ; Blanco, Juan A. ; Xu, Jianchu ; Bishop, Kevin ; Wei, Xiaohua ; Vira, Bhaskar ; Creed, Irena F. ; Mukherji, A. ; Baca, Aurelia ; Serran, Jacqueline ; Harper, Richard J. ; Aldred, David ; Sullivan, Caroline A. - \ 2018
    In: Forest and Water on a Changing Planet: Vulnerability, Adaptation and Governance Opportunities / Creed, Irena F., van Noordwijk, Meine, International Union of Forest Research Organizations (IUFRO) (IUFRO World Series ) - ISBN 9783902762955 - p. 61 - 78.
    Forest Landscape Hydrology in a ‘New Normal’ Era of Climate and Land Use Change
    Jones, Julia A. ; Wei, Xiaohua ; Noordwijk, M. van; Creed, Irena F. ; Gush, Mark ; Ellison, David ; Blanco, Juan A. ; Bishop, Kevin ; McNulty, Steven ; BarguésTobella, Aida ; Archer, E. ; Bruijnzeel, L.A. ; Duinker, P. ; Foster, David ; Gebrekirstos, Aster ; Giles-Hansen, Krysta ; Hacket-Pain, Andrew ; Harper, Richard J. ; Ilstedt, Ulrik ; Li, Qiang ; Liao, Yingchun ; Malmer, Anders ; Mwangi, Hosea ; Orland, Chloé ; Steenberg, James ; Wang, Yi ; Worthy, Fiona ; Xu, Jianchu ; Zhang, Mingfang - \ 2018
    In: Forest and Water on a Changing Planet: Vulnerability, Adaptation and Governance Opportunities / Creed, Irena F., van Noordwijk, Meine, International Union of Forest Research Organizations (IUFRO) (IUFRO World Series ) - ISBN 9783902762955 - p. 81 - 99.
    Ten essentials for action-oriented and second order energy transitions, transformations and climate change research
    Fazey, Ioan ; Schäpke, Niko ; Caniglia, Guido ; Patterson, James ; Hultman, Johan ; Mierlo, Barbara Van; Säwe, Filippa ; Wiek, Arnim ; Wittmayer, Julia ; Aldunce, Paulina ; Waer, Husam Al; Battacharya, Nandini ; Bradbury, Hilary ; Carmen, Esther ; Colvin, John ; Cvitanovic, Christopher ; D’Souza, Marcella ; Gopel, Maja ; Goldstein, Bruce ; Hämäläinen, Timo ; Harper, Gavin ; Henfry, Tom ; Hodgson, Anthony ; Howden, Mark S. ; Kerr, Andy ; Klaes, Matthias ; Lyon, Christopher ; Midgley, Gerald ; Moser, Susanne ; Mukherjee, Nandan ; Müller, Karl ; O’brien, Karen ; O’Connell, Deborah A. ; Olsson, Per ; Page, Glenn ; Reed, Mark S. ; Searle, Beverley ; Silvestri, Giorgia ; Spaiser, Viktoria ; Strasser, Tim ; Tschakert, Petra ; Uribe-Calvo, Natalia ; Waddell, Steve ; Rao-Williams, Jennifer ; Wise, Russel ; Wolstenholme, Ruth ; Woods, Mel ; Wyborn, Carina - \ 2018
    Energy Research & Social Science 40 (2018). - ISSN 2214-6296 - p. 54 - 70.
    The most critical question for climate research is no longer about the problem, but about how to facilitate the transformative changes necessary to avoid catastrophic climate-induced change. Addressing this question, however, will require massive upscaling of research that can rapidly enhance learning about transformations. Ten essentials for guiding action-oriented transformation and energy research are therefore presented, framed in relation to second-order science. They include: (1) Focus on transformations to low-carbon, resilient living; (2) Focus on solution processes; (3) Focus on ‘how to’ practical knowledge; (4) Approach research as occurring from within the system being intervened; (5) Work with normative aspects; (6) Seek to transcend current thinking; (7) Take a multi-faceted approach to understand and shape change; (8) Acknowledge the value of alternative roles of researchers; (9) Encourage second-order experimentation; and (10) Be reflexive. Joint application of the essentials would create highly adaptive, reflexive, collaborative and impact-oriented research able to enhance capacity to respond to the climate challenge. At present, however, the practice of such approaches is limited and constrained by dominance of other approaches. For wider transformations to low carbon living and energy systems to occur, transformations will therefore also be needed in the way in which knowledge is produced and used.
    Recent progress in understanding climate thresholds : Ice sheets, the Atlantic meridional overturning circulation, tropical forests and responses to ocean acidification
    Good, Peter ; Bamber, Jonathan ; Halladay, Kate ; Harper, Anna B. ; Jackson, Laura C. ; Kay, Gillian ; Kruijt, Bart ; Lowe, Jason A. ; Phillips, Oliver L. ; Ridley, Jeff ; Srokosz, Meric ; Turley, Carol ; Williamson, Phillip - \ 2018
    Progress in Physical Geography 42 (2018)1. - ISSN 0309-1333 - p. 24 - 60.
    Atlantic meridional overturning circulation - climate change - ice sheets - ocean acidification - thresholds - tropical forests
    This article reviews recent scientific progress, relating to four major systems that could exhibit threshold behaviour: ice sheets, the Atlantic meridional overturning circulation (AMOC), tropical forests and ecosystem responses to ocean acidification. The focus is on advances since the Intergovernmental Panel on Climate Change Fifth Assessment Report (IPCC AR5). The most significant developments in each component are identified by synthesizing input from multiple experts from each field. For ice sheets, some degree of irreversible loss (timescales of millennia) of part of the West Antarctic Ice Sheet (WAIS) may have already begun, but the rate and eventual magnitude of this irreversible loss is uncertain. The observed AMOC overturning has decreased from 2004–2014, but it is unclear at this stage whether this is forced or is internal variability. New evidence from experimental and natural droughts has given greater confidence that tropical forests are adversely affected by drought. The ecological and socio-economic impacts of ocean acidification are expected to greatly increase over the range from today’s annual value of around 400, up to 650 ppm CO2 in the atmosphere (reached around 2070 under RCP8.5), with the rapid development of aragonite undersaturation at high latitudes affecting calcifying organisms. Tropical coral reefs are vulnerable to the interaction of ocean acidification and temperature rise, and the rapidity of those changes, with severe losses and risks to survival at 2 °C warming above pre-industrial levels. Across the four systems studied, however, quantitative evidence for a difference in risk between 1.5 and 2 °C warming above pre-industrial levels is limited.
    Land-use and land-cover change carbon emissions between 1901 and 2012 constrained by biomass observations
    Li, Wei ; Ciais, Philippe ; Peng, Shushi ; Yue, Chao ; Wang, Yilong ; Thurner, Martin ; Saatchi, Sassan S. ; Arneth, Almut ; Avitabile, Valerio ; Carvalhais, Nuno ; Harper, Anna B. ; Kato, Etsushi ; Koven, Charles ; Liu, Yi Y. ; Nabel, Julia E.M.S. ; Pan, Yude ; Pongratz, Julia ; Poulter, Benjamin ; Pugh, Thomas A.M. ; Santoro, Maurizio ; Sitch, Stephen ; Stocker, Benjamin D. ; Viovy, Nicolas ; Wiltshire, Andy ; Yousefpour, Rasoul ; Zaehle, Sönke - \ 2017
    Biogeosciences 14 (2017)22. - ISSN 1726-4170 - p. 5053 - 5067.
    The use of dynamic global vegetation models (DGVMs) to estimate CO2 emissions from land-use and land-cover change (LULCC) offers a new window to account for spatial and temporal details of emissions and for ecosystem processes affected by LULCC. One drawback of LULCC emissions from DGVMs, however, is lack of observation constraint. Here, we propose a new method of using satellite- and inventory-based biomass observations to constrain historical cumulative LULCC emissions (ELUCc) from an ensemble of nine DGVMs based on emerging relationships between simulated vegetation biomass and ELUCc. This method is applicable on the global and regional scale. The original DGVM estimates of ELUCc range from 94 to 273 PgC during 1901–2012. After constraining by current biomass observations, we derive a best estimate of 155 ± 50 PgC (1σ Gaussian error). The constrained LULCC emissions are higher than prior DGVM values in tropical regions but significantly lower in North America. Our emergent constraint approach independently verifies the median model estimate by biomass observations, giving support to the use of this estimate in carbon budget assessments. The uncertainty in the constrained ELUCc is still relatively large because of the uncertainty in the biomass observations, and thus reduced uncertainty in addition to increased accuracy in biomass observations in the future will help improve the constraint. This constraint method can also be applied to evaluate the impact of land-based mitigation activities.
    Resource endowment and the greater good: balancing labour between family and individual fields on Beninese farms
    Paresys, Lise ; Malézieux, E. ; Huat, J. ; Kropff, Martin ; Rossing, W.A.H. - \ 2016
    In: 12th European IFSA Symposium. - Newport, UK : Harper Adams University - 14 p.
    Improved representation of plant functional types and physiology in the Joint UK Land Environment Simulator (JULES v4.2) using plant trait information
    Harper, Anna B. ; Cox, Peter M. ; Friedlingstein, Pierre ; Wiltshire, Andy J. ; Jones, Chris D. ; Sitch, Stephen ; Mercado, Lina M. ; Groenendijk, Margriet ; Robertson, Eddy ; Kattge, Jens ; Bönisch, Gerhard ; Atkin, Owen K. ; Bahn, Michael ; Cornelissen, Johannes ; Niinemets, Ülo ; Onipchenko, Vladimir ; Peñuelas, Josep ; Poorter, Lourens ; Reich, Peter B. ; Soudzilovskaia, Nadjeda A. ; Bodegom, Peter van - \ 2016
    Geoscientific Model Development 9 (2016)7. - ISSN 1991-959X - p. 2415 - 2440.

    Dynamic global vegetation models are used to predict the response of vegetation to climate change. They are essential for planning ecosystem management, understanding carbon cycle-climate feedbacks, and evaluating the potential impacts of climate change on global ecosystems. JULES (the Joint UK Land Environment Simulator) represents terrestrial processes in the UK Hadley Centre family of models and in the first generation UK Earth System Model. Previously, JULES represented five plant functional types (PFTs): broadleaf trees, needle-leaf trees, C3 and C4 grasses, and shrubs. This study addresses three developments in JULES. First, trees and shrubs were split into deciduous and evergreen PFTs to better represent the range of leaf life spans and metabolic capacities that exists in nature. Second, we distinguished between temperate and tropical broadleaf evergreen trees. These first two changes result in a new set of nine PFTs: tropical and temperate broadleaf evergreen trees, broadleaf deciduous trees, needle-leaf evergreen and deciduous trees, C3 and C4 grasses, and evergreen and deciduous shrubs. Third, using data from the TRY database, we updated the relationship between leaf nitrogen and the maximum rate of carboxylation of Rubisco (Vcmax), and updated the leaf turnover and growth rates to include a trade-off between leaf life span and leaf mass per unit area. Overall, the simulation of gross and net primary productivity (GPP and NPP, respectively) is improved with the nine PFTs when compared to FLUXNET sites, a global GPP data set based on FLUXNET, and MODIS NPP. Compared to the standard five PFTs, the new nine PFTs simulate a higher GPP and NPP, with the exception of C3 grasses in cold environments and C4 grasses that were previously over-productive. On a biome scale, GPP is improved for all eight biomes evaluated and NPP is improved for most biomes - the exceptions being the tropical forests, savannahs, and extratropical mixed forests where simulated NPP is too high. With the new PFTs, the global present-day GPP and NPP are 128 and 62 Pg C year-1, respectively. We conclude that the inclusion of trait-based data and the evergreen/deciduous distinction has substantially improved productivity fluxes in JULES, in particular the representation of GPP. These developments increase the realism of JULES, enabling higher confidence in simulations of vegetation dynamics and carbon storage.

    Shear-induced fibrous structure formation from a pectin/SPI blend
    Dekkers, Birgit L. ; Nikiforidis, Costas ; Goot, Atze Jan van der - \ 2016
    Innovative Food Science and Emerging Technologies 36 (2016). - ISSN 1466-8564 - p. 193 - 200.
    Biopolymer incompatibility - Fibrous structure - High temperature shear cell - Protein-polysaccharide blend - Shear-induced structuring

    Well-defined shear flow can be applied to create fibrous, anisotropic samples from biopolymers when present at sufficiently high dry matter contents. Anisotropic biopolymer structures are of high interest especially when made from plant-based polymer blends due to novel food applications, like meat replacers. We investigate shear-induced structuring of a pectin/soy protein isolate (SPI) blend under heating. Scanning Electron Microscope analysis revealed that shear-induced structuring resulted in elongated pectin filaments, oriented in the direction of the shear flow, being entrapped in a continuous protein phase, inducing anisotropy in the blend. The length of the pectin filaments increased upon higher pectin concentrations and shearing temperatures, leading both to higher anisotropy, as measured with the tensile strength analysis. The fibrous appearance of samples became more evident when deforming the product by tearing, which effect was thought to be caused by detachment through or along the long side of the pectin filament. Industrial relevance The efficient preparation of fibrous products based on plant materials is of interest, because these products can be a starting point for the development of meat replacers. Meat replacers made from plant material are a promising, innovative, and sustainable source of protein for human consumption. With an increasing world population, creation of innovative sources of protein are needed to be able to feed everyone (United Nations - Department of Economic and Social Affairs, 2015). Proteins from plant sources, such as soy, are preferred over proteins from animal origin because plant based materials, for example, have lower environmental impact (Day, 2013; Mogensen, Hermansen, Halberg, Dalgaard, R., Vis, & Smith, 2009). In order to replace meat by a plant-based meat replacer, it is important that a similar product in terms of structural properties is developed to improve consumer acceptance (Hoek et al., 2011). Meat replacers are often produced with extrusion cooking, which is a process that has been applied for texturization of plant materials in the application of meat replacers for decades (Campbell, 1981; Harper & Clark, 1978). Previous research showed that a novel technique based on well-defined shear flow can also be used to create fibrous, anisotropic structures from plant-based biopolymers at sufficiently high dry matter contents, with a cone–cone device (Shear Cell) or a concentric cylinder device (Couette Cell) (Grabowska, Tekidou, Boom, & van der Goot, 2014; G. A. Krintiras, Göbel, Bouwman, van der Goot, & Stefanidis, 2014; Manski, van der Goot, & Boom, 2007). This novel technique uses milder conditions for structure formation, due to lower applied shear forces, and has therefore a lower specific mechanical energy input (Grabowska et al., 2016; G.A. Krintiras, Gadea Diaz, van der Goot, Stankiewicz, & Stefanidis, 2015).

    Robots for agriculture will require new start-up companies to manufacture them
    Henten, Eldert van - \ 2015

    A British professor says large farm machinery engineering will be replaced by small start-up companies.Agricultural robots are touted as the future for saving time, money and energy but also reducing damage on soils.Professor Simon Blackmore, the head of engineering at Harper Adams University in the United Kingdom, says the large tractors have become too heavy."Analysing the current systems, we're actually seeing as many problems from the big machines as they have solved in the past," said Professor Blackmore."I estimate that up to 90 per cent of the energy that goes into cultivation is there to repair the damage that the big tractors have caused in the first place."Every year we cultivate, every year we damage. The following year we cultivate, then we damage, and so on every year.

    "So how we move precision farming forward is by using lighter machinery!"

    As an agricultural engineer, Professor Blackmore saw the future is robotics, without cutting people out of a job. "People will no longer need to sit in a tractor for up to 16 hours a day, but farm managers will still manage, operators will need to look after the machines," he said.In Australia, all the large tractors bought for farms are imported. But that could change if small start-up companies develop the smaller machines, and Professor Blackmore said that has to happen. He said agricultural robots were a major disruption to the production line of big manufacturers. "We've had a very linear development of agricultural machinery and they've got bigger all the time. With economies of scale, manufacturers have just made bigger and bigger vehicles," he said. "I'm envisaging a complete new mechanisation system that doesn't really base itself on what we've done in the past, but on what we need now, away from industrial production, into flexible manufacturing, as we've seen in industry." Professor Blackmore said robots would be adaptable to weather and world prices."It will be start-up companies spearheading agricultural robots in the near future," he said.The Australian Centre of Field Robotics, at the University of Sydney, is one of the leading such centres in the world. There Dr James Underwood has under development the small car-size robots that can muster dairy cows, take their temperatures and potentially spray weeds in the paddock.

    Dutch robot picks peppers

    Robots are already in development at the University of Wageningen, in the Netherlands, to pick red peppers or capsicum.Professor of engineering Eldert van Henten is developing the robot picker for indoor crops. Just half a percent of Dutch farmland is devoted to protected cropping. Yet out of those greenhouses, covering 10,000 hectares, comes 35 per cent of the value of Dutch agricultural produce, which bodes well for the need to feed nine billion people from shrinking farmland. "It's a very powerful way for producing crops, because you can protect them from the environment, and change the climate indoors and carbon dioxide levels and lift productivity massively," said Dr van Henten. "We have been building a robot to harvest sweet peppers because we have a big problem with the availability of skilled labour."To get a robot to recognise the fruit, first it has to find it, which is complicated for a blind machine.It also has to judge that the pepper is ripe and then grasp it. Dr van Henten said greenhouses might have to be redeveloped to cope especially with robots. He agreed that it was not large machinery manufacturers who would develop these robots. "I see some very young spin-offs from university using this technology, because they are open to using this technology for the future."

    The presence of a below-ground neighbour alters within-plant seed size distribution in Phaseolus vulgaris
    Chen, B. ; During, H.J. ; Vermeulen, P.J. ; Anten, N.P.R. - \ 2014
    Annals of Botany 114 (2014). - ISSN 0305-7364 - p. 937 - 943.
    root competition - variable environments - optimal balance - number - recognition - germination - growth - consequences - adaptation - plasticity
    * Background and Aims Considerable variation in seed size commonly exists within plants, and is believed to be favoured under natural selection. This study aims to examine the extent to which seed size distribution depends on the presence of competing neighbour plants. * Methods Phaseolus vulgaris plants rooting with or without a conspecific neighbourwere grown in soil with high or low nutrient availability. Seeds were harvested at the end of the growth cycle, the total nitrogen and phosphorus invested in seed production were measured and within-plant seed size distribution was quantified using a set of statistical descriptors. * Key Results Exposure to neighbours’ roots induced significant changes in seed size distribution. Plants produced proportionally more large seeds and fewer small ones, as reflected by significant increases in minimal seed size, mean seed size, skewness and Lorenz asymmetry coefficient. These effects were different from, and in several cases opposite to, the responses when the soil nutrient level was reduced, and were significant after correction for the amount of resources invested in seed production. * Conclusions Below-ground neighbour presence affects within-plant seed size distribution in P. vulgaris. This effect appears to be non-resource-mediated, i.e. to be independent of neighbour-induced effects on resource availability. It implies that, based on current environmental cues, plants can make an anticipatory adjustment of their investment strategy in offspring as an adaptation to the local environment in the future. Key words: Anticipatory maternal effect, bet-hedging, game theory, neighbour detection, Phaseolus vulgaris, kidney bean, root competition, seed-setting, seed size variation, size inequality, skewness. INTRODUCTION A considerable degree of variation in seed size within plants is commonly observed (Michaels et al., 1988; Silvertown, 1989; Ruiz de Clavijo, 2002; Vo¨ller et al., 2012). Such variation is often interpreted as an adaptive bet-hedging strategy (Harper et al., 1970; McGinley et al., 1987; McGinley and Charnov, 1988; Venable and Brown, 1988; Geritz, 1995). Many studies also reveal that plants modify the pattern of variation (i.e. distribution) to cope with their abiotic environmental conditions (e.g. temperature, Wulff, 1986; light, Galloway, 2001; nutrients, Galloway, 2001;water, Parciak, 2002). Herewe demonstrate that seed size distribution may also be modified in response to the presence of a below-ground neighbour. Within a species, seed size (following common practice, seed size refers to seedweight in this paper) often correlates positively with the competitiveness of the offspring (e.g. Houssard and Escarre´, 1991; Eriksson, 1999; Lehtila¨ and Ehrle´n, 2005; Dubois and Cheptou, 2012). Based on the trade-off, induced by resource limitation in plants, between competition (favours large seeds) and colonization (favours a large number of small seeds), Geritz (1995) extended an optimal offspring size model (Smith and Fretwell, 1974) by considering seedling competition and using
    From OpenMI 1.4 to 2.0
    Gijsbers, P. ; Hummel, S. ; Vanechek, S. ; Groos, J. ; Harper, A. ; Knapen, M. ; Gregersen, J. ; Schade, P. ; Antonello, A. ; Donchyts, G. - \ 2010
    In: Modelling for Environment's Sake. - - p. 1081 - 1088.
    Integrated modelling - Linking - Model interoperability - Open Modelling Interface
    The Open Modelling Interface (OpenMI) was launched end of 2005 with the aim to become a global standard for linking models and tools in the environmental domain with focus on water. Over the past few years, the user and development community has grown substantially and various well known models have become compliant. Some of the uses did not adopt the OpenMI.Standard interfaces completely, but used a slight deviation to achieve their goal in a similar style. Improvements would be necessary to become a true global interface standard instead of a style for developing new model codes. Starting in 2007, a core group of six institutes has worked on an upgrade of the OpenMI towards version 2.0. A long list of deficiencies was composed, having a few use cases as general guidance for improvement. The proposed redesign, based on similar leading concepts and a similar data model, required however a non-backward compatible upgrade of the interface standard to remove the weak points from the first version. This decision allowed the OpenMI to become more suitable for a larger range of applications, from non-time dependent Geographical Information Systems (GIS) towards e.g. master-slave controlled modelling frameworks. The OpenMI 2.0 standard has been open for review early 2010. Once completed and processed, the release of OpenMI 2.0, in both C# and Java is expected late 2010. This paper will discuss the reasons for change in more detail and highlights how the proposed solution meets the needs in a better way.
    Baculovirus expression system
    Oers, M.M. van; Vlak, J.M. - \ 2008
    In: Encyclopedia of life sciences / Harper, D., Chichester : John Wiley and Sons - ISBN 9780470066515 - 18348 p.
    Processes influencing aquatic fauna
    Gore, J.A. ; Mead, J. ; Penczak, T. ; Higler, L. ; Kemp, J. - \ 2008
    In: Ecohydrology. Processes, models and case studies / Harper, D., Zalewski, M., Pacini, N., Wallingford : CABI - ISBN 9781845930028 - p. 62 - 87.
    The PAS fold: A redefinition of the PAS domain based upon structural prediction. A large-scale homology modelling study
    Hefti, M.H. ; Francoijs, C.J.J. ; Vries, S.C. de; Dixon, R. ; Vervoort, J.J.M. - \ 2004
    European Journal of Biochemistry 271 (2004)6. - ISSN 0014-2956 - p. 1198 - 1208.
    photoactive yellow protein - plant photoreceptor domain - minded gene encodes - oxygen sensor fixl - signal-transduction - photocycle intermediate - flavin mononucleotide - rhizobium-meliloti - circadian-rhythms - escherichia-coli
    In the postgenomic era it is essential that protein sequences are annotated correctly in order to help in the assignment of their putative functions. Over 1300 proteins in current protein sequence databases are predicted to contain a PAS domain based upon amino acid sequence alignments. One of the problems with the current annotation of the PAS domain is that this domain exhibits limited similarity at the amino acid sequence level. It is therefore essential, when using proteins with low-sequence similarities, to apply profile hidden Markov model searches for the PAS domain-containing proteins, as for the PFAM database. From recent 3D X-ray and NMR structures, however, PAS domains appear to have a conserved 3D fold as shown here by structural alignment of the six representative 3D-structures from the PDB database. Large-scale modelling of the PAS sequences from the PFAM database against the 3D-structures of these six structural prototypes was performed. All 3D models generated (> 5700) were evaluated using PROSAII. We conclude from our large-scale modelling studies that the PAS and PAC motifs (which are separately defined in the PFAM database) are directly linked and that these two motifs form the PAS fold. The existing subdivision in PAS and PAC motifs, as used by the PFAM and SMART databases, appears to be caused by major differences in sequences in the region connecting these two motifs. This region, as has been shown by Gardner and coworkers for human PAS kinase (Amezcua, C.A., Harper, S.M., Rutter, J. & Gardner, K.H. (2002) Structure10, 1349-1361, [1]), is very flexible and adopts different conformations depending on the bound ligand. Some PAS sequences present in the PFAM database did not produce a good structural model, even after realignment using a structure-based alignment method, suggesting that these representatives are unlikely to have a fold resembling any of the structural prototypes of the PAS domain superfamily.
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