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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Fertile cities: Nutrient management practices in urban agriculture
Wielemaker, Rosanne ; Oenema, Oene ; Zeeman, Grietje ; Weijma, Jan - \ 2019
Science of the Total Environment 668 (2019). - ISSN 0048-9697 - p. 1277 - 1288.
Fertilizer use - Nitrogen - Organic matter - Phosphorus - Potassium - Urban farming

Cities are increasingly targeted as centers for sustainable development and innovation of food systems. Urban agriculture (UA) is advocated by some as a multi-faceted approach to help achieve urban sustainability goals as it provides possible social, economic and environmental benefits. The role of UA in restoring resource cycles receives increasing attention, especially with regard to assimilating urban waste. However, there is little information on how nutrients are managed in UA in industrialized countries. To examine nutrient management in UA, data was collected from a total of 25 ground-based UA initiatives in the Netherlands on i) preferences for types of fertilizers, and ii) quantity and quality of fertilizers used including nutrient composition and organic matter content. The main inputs at urban farms were compost and manure, high in organic matter content. The total nutrient inputs were compared to nutrient demand, based on crop nutrient uptake, in order to determine nutrient balances. Results show that mean nutrient inputs exceeded mean crop demand by roughly 450% for total nitrogen, 600% for phosphorus and 250% for potassium. Mean inputs for plant-available nitrogen were comparable to crop uptake values. The surpluses, particularly for phosphorus, are higher than fertilizer application limits used for conventional farming in The Netherlands. While nutrient input calculations were subject to several uncertainties, e.g., due to lack of accuracy of the data supplied by the farmers, results show a salient indication of over-fertilization and thus a suboptimal nutrient use. If UA continues to expand across cities these observed nutrient surpluses may pose a risk for local surface waters and groundwater as well as soil quality. The need to improve nutrient management in UA is evident. Soil tests, harvest logging and book keeping of nutrient inputs would improve data quality and may help balance nutrient inputs with nutrient outputs.

Recycling nutrients contained in human excreta to agriculture: Pathways, processes, and products
Harder, Robin ; Wielemaker, Rosanne ; Larsen, Tove A. ; Zeeman, Grietje ; Öberg, Gunilla - \ 2019
Critical Reviews in Environmental Science and Technology 49 (2019)8. - ISSN 1064-3389 - p. 695 - 743.
blackwater - carbon - feces - fertilizer - nitrogen - organic matter - Phosphorus - potassium - recovery - resource-oriented sanitation - sewage - soil amendment - source-separation - urine - wastewater

The need for better nutrient management has spurred efforts towards more comprehensive recycling of nutrients contained in human excreta to agriculture. Research in this direction has intensified throughout the past years, continuously unfolding new knowledge and technologies. The present review aspires to provide a systematic synthesis of the field by providing an accessible overview of terminology, recovery pathways and treatment options, and products rendered by treatment. Our synthesis suggests that, rather than focusing on a specific recovery pathway or product and on a limited set of nutrients, there is scope for exploring how to maximize nutrient recovery by combining individual pathways and products and including a broader range of nutrients. To this end, finding ways to more effectively share and consolidate knowledge and information on recovery pathways and products would be beneficial. The present review aims to provide a template that aims to facilitate designing human excreta management for maximum nutrient recovery, and that can serve as foundation for organizing and categorizing information for more effective sharing and consolidation.

Harvest to harvest : Recovering nutrients with New Sanitation systems for reuse in Urban Agriculture
Wielemaker, Rosanne C. ; Weijma, Jan ; Zeeman, Grietje - \ 2018
Resources, Conservation and Recycling 128 (2018). - ISSN 0921-3449 - p. 426 - 437.
New Sanitation - Nutrients - Organic matter - Urban Agriculture - Urban Harvest Approach - Urban metabolism

To maintain the city as a viable concept for human dwelling in the long term, a circular metabolism needs to be adopted that relies on recovering, reusing and recycling resources, in which output ('waste') from one metabolic urban conversion equals input for another. Urban Agriculture (UA) and source-separation-based New Sanitation (NS) are gaining momentum as measures for improved urban resource management. UA aims to localize food provisioning while NS aims to reorganize wastewater and organic waste management to recover valuable and crucial resources. The objective of this paper is to assess the match between the supply by NS systems and the demand from UA for nitrogen, phosphorus and organic matter, in terms of quantity and quality, to foster a circular metabolism. The research is contextualized in the city of Rotterdam. The methodology used is based on the Urban Harvest Approach (UHA), developed previously for the urban water cycle. Novel to this research is adapting the UHA to nitrogen, phosphorus and organic matter loads for two practiced UA typologies (ground-based and rooftop) and four NS concepts for the treatment of domestic urine, feces and organic kitchen waste. Results show that demand for nutrients and organic matter from UA can be minimized by 65-85% and a self-sufficiency of 100% for phosphorus can be achieved, while partial self-sufficiency for nitrogen and organic matter. This research reveals that integration of NS and UA maximizes urban self-sufficiency.

How plausible is automatic annotation of scientific spreadsheets?
Vos, Martine De; Wielemaker, Jan ; Wielinga, Bob ; Schreiber, Guus ; Top, Jan - \ 2017
CEUR Workshop Proceedings 2065 (2017). - ISSN 1613-0073 - p. 26 - 31.
Domain knowledge - Heuristics - Knowledge engineering - Spreadsheets - Vocabularies
It is possible to automatically annotate a natural science spreadsheet using lexical matching, given that the tables in these spreadsheets meet a number of requirements regarding the content. Results of a survey show that most of the existing natural science spreadsheets deviate from the ideal situation. We propose to complement lexical matching with both heuristics and knowledge from external vocabularies to overcome these deviations.
Combining information on structure and content to automatically annotate natural science spreadsheets
Vos, Martine de; Wielemaker, Jan ; Rijgersberg, Hajo ; Schreiber, Guus ; Wielinga, Bob ; Top, Jan - \ 2017
International Journal of Human-Computer Studies 103 (2017). - ISSN 1071-5819 - p. 63 - 76.
Domain Model - Implicit knowledge - Methodology - Spreadsheets - Units of measure - Vocabularies

In this paper we propose several approaches for automatic annotation of natural science spreadsheets using a combination of structural properties of the tables and external vocabularies. During the design process of their spreadsheets, domain scientists implicitly include their domain model in the content and structure of the spreadsheet tables. However, this domain model is essential to unambiguously interpret the spreadsheet data. The overall objective of this research is to make the underlying domain model explicit, to facilitate evaluation and reuse of these data. We present our annotation approaches by describing five structural properties of natural science spreadsheets, that may pose challenges to annotation, and at the same time, provide additional information on the content. For example, the main property we describe is that, within a spreadsheet table, semantically related terms are grouped in rectangular blocks. For each of the five structural properties we suggest an annotation approach, that combines heuristics on the property with knowledge from external vocabularies. We evaluate our approaches in a case study, with a set of existing natural science spreadsheets, by comparing the annotation results with a baseline based on purely lexical matching. Our case study results show that combining information on structural properties of spreadsheet tables with lexical matching to external vocabularies results in higher precision and recall of annotation of individual terms. We show that the semantic characterization of blocks of spreadsheet terms is an essential first step in the identification of relations between cells in a table. As such, the annotation approaches presented in this study provide the basic information that is needed to construct the domain model of scientific spreadsheets.

Harvest to harvest - Recovering nitrogen, phosphorus and organic matter via new sanitation systems for reuse in urban agriculture
Wielemaker, Rosanne - \ 2015
Requirements for the domain model of environmental computational spreadsheets
Top, J.L. ; Vos, M. de; Wielemaker, J. ; Schreiber, M. - \ 2015
A methodology for constructing the calculation model of scientific spreadsheets
Vos, M. de; Wielemaker, J. ; Schreiber, G. ; Wielinga, B. ; Top, J.L. - \ 2015
Spreadsheets models are frequently used by scientists to analyze research data. These models are typically described in a paper or a report, which serves as single source of information on the underlying research project. As the calculation workflow in these models is not made explicit, readers are not able to fully understand how the research results are calculated, and trace them back to the underlying spreadsheets. This paper proposes a methodology for semi-automatically deriving the calculation workflow underlying a set of spreadsheets. The starting point of our methodology is the cell dependency graph, representing all spreadsheet cells and connections. We automatically aggregate all cells in the graph that represent instances and duplicates of the same quantities, based on analysis of the formula syntax. Subsequently, we use a set of heuristics, incorporating knowledge on spreadsheet design, computational procedures and domain knowledge, to select those quantities, that are relevant for understanding the calculation workflow. We explain and illustrate our methodology by actually applying it on three sets of spreadsheets from existing research projects in the domains of environmental and life science. Results from these case studies show that our constructed calculation models approximate the ground truth calculation workflows, both in terms of content and size, but are not a perfect match.
Biophysical control of intertidal benthic macroalgae revealed by high-frequency multispectral camera images
Wal, Daphne van der; Dalen, Jeroen van; Wielemaker-van den Dool, Annette ; Dijkstra, Jasper T. ; Ysebaert, Tom - \ 2014
Journal of Sea Research 90 (2014). - ISSN 1385-1101 - p. 111 - 120.
Intertidal benthic macroalgae are a biological quality indicator in estuaries and coasts. While remote sensing has been applied to quantify the spatial distribution of such macroalgae, it is generally not used for their monitoring. We examined the day-to-day and seasonal dynamics of macroalgal cover on a sandy intertidal flat using visible and near-infrared images from a time-lapse camera mounted on a tower. Benthic algae were identified using supervised, semi-supervised and unsupervised classification techniques, validated with monthly ground-truthing over one year. A supervised classification (based on maximum likelihood, using training areas identified in the field) performed best in discriminating between sediment, benthic diatom films and macroalgae, with highest spectral separability between macroalgae and diatoms in spring/summer. An automated unsupervised classification (based on the Normalised Differential Vegetation Index NDVI) allowed detection of daily changes in macroalgal coverage without the need for calibration. This method showed a bloom of macroalgae (filamentous green algae, Ulva sp.) in summer with >. 60% cover, but with pronounced superimposed day-to-day variation in cover. Waves were a major factor in regulating macroalgal cover, but regrowth of the thalli after a summer storm was fast (2. weeks). Images and in situ data demonstrated that the protruding tubes of the polychaete Lanice conchilega facilitated both settlement (anchorage) and survival (resistance to waves) of the macroalgae. Thus, high-frequency, high resolution images revealed the mechanisms for regulating the dynamics in cover of the macroalgae and for their spatial structuring. Ramifications for the mode, timing, frequency and evaluation of monitoring macroalgae by field and remote sensing surveys are discussed.
5 - vragen over - teken - door Alexander Wielemaker
Vliet, Arnold van - \ 2012
5 - door Alexander Wielemaker - vragen over - teken
Vliet, Arnold van - \ 2012
Rural Development and Sustainable Land Use in the Hillsides of Honduras
Jansen, H.P.G. ; Pender, J. ; Damon, A. ; Wielemaker, W. ; Schipper, R.A. - \ 2007
In: Sustainable Poverty Reduction in Less-favoured Areas / Ruben, R, Pender, J, Kuyvnhoven, A, Wallingford, UK : CABI - ISBN 9781845932770 - p. 159 - 180.
Policies for sustainable development in the hillside areas of Honduras: a quantitative livelihoods approach
Jansen, H.P.G. ; Pender, J. ; Damon, A. ; Wielemaker, W. ; Schipper, R.A. - \ 2006
Agricultural Economics 34 (2006)2. - ISSN 0169-5150 - p. 141 - 153.
strategies - adoption - diversification
In this article, we use data for 376 households, 1,066 parcels, and 2,143 plots located in 95 villages in the hillside areas in Honduras to generate information needed by decision makers to assess the needs and opportunities for public investments, and design policies that stimulate natural resource conservation. We develop a quantitative livelihood approach, using factor and cluster analysis to group households based on the use of their main assets. This resulted in seven household categories that pursue similar livelihood strategies. We use a multinomial logit model to show that livelihood strategies are determined by comparative advantages as reflected by a combination of biophysical and socioeconomic variables. While 92% of the rural hillsides population in Honduras lives on US$1.00/capita/day or less, households that follow a livelihood strategy based on basic grain farming are the poorest because they often live in isolated areas with relatively poor agro-ecological and socioeconomic conditions. Opportunities for off-farm work tend to be limited in these areas and household strategies that combine on-farm work with off-farm work earn higher incomes. Per capita incomes can be increased by improving road infrastructure, widening access to land, policies that reduce household size and dependency ratios, and adoption of sustainable land management technologies that restore soil fertility. We used probit models to show that the latter can be promoted by agricultural extension programs and land redistribution. Investments in physical assets should be directed toward households that pursue livelihood strategies based on off-farm employment or coffee production, while agricultural training programs are best focused on livestock producers.
Politicas para el desarrollo sostenible de las laderas de Honduras
Jansen, H.G.P. ; Damon, A. ; Pender, J. ; Wielemaker, W. ; Schipper, R.A. - \ 2003
Sustainable development in the Hillsides of Honduras: A livelihoods approach
Jansen, H.G.P. ; Damon, A. ; Pender, J. ; Wielemaker, W. ; Schipper, R.A. - \ 2003
Over vulkaankegels, lavastromen, heidevelden en ooibossen
Ketner, P. ; Wielemaker, W. - \ 2002
Natura 99 (2002)6. - ISSN 0028-0631 - p. 192 - 194.
geologie - geomorfologie - landschap - vulkanische gebieden - vulkanen - vegetatie - frankrijk - geology - geomorphology - landscape - volcanic areas - volcanoes - vegetation - france
Beschrijving van de geologische ontstaansgeschiedenis, bodem, landschap en vegetatie in de Auvergne, een gebied dat de effecten van vulkanisme in al zijn vormenrijkdom duidelijk laat zien
The conditioning and knowledge-creating view: Managing the source of the strategy process
Wielemaker, M. ; Elfring, T. - \ 2001
In: Proceedings of the 21st Annual International conference of the Strategic Management Society : The 21st Annual International conference of the Strategic Management Society, San Francisco, 2001. - [S.l.] : [s.n.], 2001
How well-established firms prepare for the new economy; An empirical study of the developments of new economy initiatives
Wielemaker, M.W. ; Elfring, T. ; Volberda, H.W. - \ 2001
International Studies of Management & Organization 31 (2001)1. - ISSN 0020-8825 - p. 7 - 29.
Significance and application of the multi-hierarchical landsystem in soil mapping
Wielemaker, W.G. ; Bruin, S. de; Epema, G.F. ; Veldkamp, A. - \ 2001
Catena 43 (2001). - ISSN 0341-8162 - p. 15 - 34.
landevaluatie - bodemkarteringen - methodologie - nederland - landschap - land evaluation - soil surveys - landscape - methodology - netherlands
Late-cenozoic landscape development : the lower Guadalhorce Valley
Schoorl, J.M. ; Veldkamp, A. ; Berg, R.M. van den; Buurman, P. ; Wielemaker, W.G. - \ 2000
In: Book of abstracts : Vijfde Nederlands Aardwetenschappelijk Congres, Veldhoven, 20 en 21 april 2000 - p. 3.29 - 3.29.
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