Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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Food or furniture: Separating trophic and non-trophic effects of Spanish moss to explain its high invertebrate diversity
Borst, Annieke C.W. ; Angelini, Christine ; Berge, Anne ten; Lamers, Leon ; Derksen-Hooijberg, Marlous ; Heide, Tjisse van der - \ 2019
Ecosphere 10 (2019)9. - ISSN 2150-8925
brown food web - detritus - feeding guilds - food provisioning - foundation species - habitat complexity - habitat structure - non-trophic interactions - patch size - species richness - surface area

Foundation species are typically suggested to enhance community diversity non-trophically by increasing habitat structure and mitigating physical stress, while their trophic role is considered of minor importance. Yet, there is little experimental evidence on the relative importance of trophic and non-trophic effects and the interaction with patch size. Here, we transplanted different festoon sizes of living Tillandsia usneoides (Spanish moss) and structural mimics assessing the trophic and non-trophic roles of this habitat-forming epiphyte in mediating the invertebrate community. Compared to bare branches, mimics enhanced species and feeding guild richness and abundances, but living festoons even more so, demonstrating that trophic and non-trophic effects jointly stimulated the community. Specifically, our results show that, independent of patch size, 40% of the total species richness and 46% of total guild richness increase could be contributed to habitat structure alone, while Spanish moss trophically stimulated these metrics by another 60% and 54%. As detritivores were particularly enhanced in living festoons, our findings suggest that trophic stimulation occurred primarily through the provisioning of Spanish moss detritus. Our results highlight that foundation species can facilitate their associated communities through both trophic and non-trophic pathways, calling for studies addressing their indirect trophic role via the brown food web.

Diergeneesmiddelen in het milieu - een synthese van de huidige kennis
Moermond, Caroline ; Lahr, Joost ; Montforts, Mark ; Derksen, Anja ; Bondt, Nico ; Puister-Jansen, Linda ; Koeijer, Tanja de; Hoeksma, Paul - \ 2019
Bilthoven : Rijksinstituut voor Volksgezondheid en Milieu (RIVM) - 15
Diergeneesmiddelen in het milieu : een synthese van de huidige kennis
Lahr, Joost ; Moermond, Caroline ; Montforts, Mark ; Derksen, Anja ; Bondt, Nico ; Puister-Jansen, Linda ; Koeijer, Tanja de; Hoeksma, Paul - \ 2019
Amersfoort : Stowa (Stowa rapport 2019-26) - ISBN 9789057738616 - 117
Timing it right: Non-consumptive effects on prey recruitment magnify overtime
Bertolini, C. ; Capelle, J.J. ; Timmermans, K. ; Bouma, T.J. ; De Koppel, J. Van; Derksen, G.C.H. - \ 2019
Journal of Experimental Marine Biology and Ecology 513 (2019). - ISSN 0022-0981 - p. 47 - 54.
Predator-prey - Indirect interactions - Population dynamics - Benthic ecology - Mytilus edulis - Asterias rubens
Many organisms rely on chemical signals and cues to determine habitat suitability and safety. Chemical signals can mediate many interactions, including those between predators and their prey. Altering prey behaviour, these non-consumptive effects (NCEs) can influence population and community dynamics. Understanding how NCEs influence early life history stages, such as ‘decisions’ of benthic species with planktonic larvae about where to settle, can provide useful information on the ecological functioning of these systems as well as the management for commercial usage, although most studies have so far focused on intertidal systems which are already subject to a set of stressful conditions. With a shallow subtidal field experiment we investigated NCEs of the common starfish Asterias rubens on one of its main preys, the blue mussels Mytilus edulis. We tested the hypotheses that (1) the presence of starfish reduces mussels settlement and that (2) the mussels that settle will invest more energy towards induced defences than to growth, and will thus remain smaller than mussels settling in an area without starfish. Two independent trials revealed a significant reduction of mussel spat on the collectors in the presence of starfish after a two-week deployment period. There was however no effect of starfish on the size distribution of the mussel spat. The delayed observation of effects of starfish, absent after the first week but evident afterwards, suggests a time dependency of NCE's on spat settlement. Harnessing this ecologically important information has the potential to increase yield of mussel seeds available for fisheries by either removing starfish from the ground-based settling areas at the onset and for the duration of spatfall or by using floating substrates that are away from the bottom-bound starfish. Moreover, these results also underlines the potential of using predator cues in the application for sustainable natural antifouling compounds in situations with low recruitment pressures.
Comparison of madder (Rubia tinctorum L.) and weld (Reseda luteola L.) total extracts and their individual dye compounds with regard to their dyeing behaviour, colour, and stability towards light
Willemen, Hendra ; Meijdenberg, Geeske J.P. van den; Beek, Teris A. van; Derksen, Goverdina C.H. - \ 2019
Coloration Technology 135 (2019)1. - ISSN 1472-3581 - p. 40 - 47.

This paper reports on the colorimetric properties of natural dyes from madder and weld plants. For both crops, a comparison is made among several individual dye compounds and the total plant extracts. Dyeing properties, colour properties and colour stability have been studied. Insight has been gained into the role of the major dye compounds present in the plant. For madder as well as for weld, the use of the total plant extract is considered to be advantageous over the use of individual dye compounds in terms of solubility, colour tone and stability towards light, and non-coloured components present in the plant extract are considered to be responsible for increasing the solubility and the stability of the dye compounds.

Photo-stability of a flavonoid dye in presence of aluminium ions
Villela, Alexandre ; Vuuren, Monique S.A. van; Willemen, Hendra M. ; Derksen, Goverdina C.H. ; Beek, Teris A. van - \ 2019
Dyes and Pigments 162 (2019). - ISSN 0143-7208 - p. 222 - 231.
Flavonoid - Light-fastness - Luteolin - Natural dye - Reseda luteola - Weld

The main colouring compounds of the dye plant weld (Reseda luteola L.) are the flavones luteolin (lut), lut-7-O-glucoside and lut-7,3ʹ-O-diglucoside. Alum (an aluminium salt)-premordanted wool dyed with weld leads to yellow colours that are of low resistance to light. The photo-stability of lut in aerated methanol–water 8:2 (v/v) solution upon irradiation with light above 300 nm was studied at different lut–Al3+ ratios. Experiments using extracts of weld to dye wool premordanted with increasing quantities of aluminium salts were also carried out. The photo-stability of lut in the polar protic solvent and the photo-resistance (light-fastness) of the colour of weld-dyed wool decrease with increasing concentrations of aluminium ions. Thus, the lower the [Al3+] used for mordanting the wool, the more light-fast its colour. Lowering the [Al3+] appears to have no negative influence on the wash-fastness of the colour. As the gain in light-fastness by the use of low [Al3+] to premordant the wool is not extensive, however, this does not seem to be a way to meet today's requirement of light-fastness of the colours of dyed textiles by itself. Nevertheless, it may be part of a bigger strategy to address the need for increased light-fastness of the colour of wool dyed with weld. Implementation of this approach by dyers is expected to clarify whether it results in benefits for textile dyeing practice.

Foundation species enhance food web complexity through non-trophic facilitation
Borst, Annieke C.W. ; Verberk, Wilco C.E.P. ; Angelini, Christine ; Schotanus, Jildou ; Wolters, Jan Willem ; Christianen, Marjolijn J.A. ; Zee, Els M. van der; Derksen-Hooijberg, Marlous ; Heide, Tjisse van der - \ 2018
PLoS ONE 13 (2018)8. - ISSN 1932-6203

Food webs are an integral part of every ecosystem on the planet, yet understanding the mechanisms shaping these complex networks remains a major challenge. Recently, several studies suggested that non-trophic species interactions such as habitat modification and mutualisms can be important determinants of food web structure. However, it remains unclear whether these findings generalize across ecosystems, and whether non-trophic interactions affect food webs randomly, or affect specific trophic levels or functional groups. Here, we combine analyses of 58 food webs from seven terrestrial, freshwater and coastal systems to test (1) the general hypothesis that non-trophic facilitation by habitat-forming foundation species enhances food web complexity, and (2) whether these enhancements have either random or targeted effects on particular trophic levels, functional groups, and linkages throughout the food web. Our empirical results demonstrate that foundation species consistently enhance food web complexity in all seven ecosystems. Further analyses reveal that 15 out of 19 food web properties can be well-approximated by assuming that foundation species randomly facilitate species throughout the trophic network. However, basal species are less strongly, and carnivores are more strongly facilitated in foundation species’ food webs than predicted based on random facilitation, resulting in a higher mean trophic level and a longer average chain length. Overall, we conclude that foundation species strongly enhance food web complexity through non-trophic facilitation of species across the entire trophic network. We therefore suggest that the structure and stability of food webs often depends critically on non-trophic facilitation by foundation species.

Diergeneesmiddelen & hormonen in het milieu door de toediening van drijfmest : Een verkennende studie in de Provincie Gelderland naar antibiotica, antiparasitaire middelen, coccidiostatica en natuurlijke hormonen in mest, (water)bodem, grondwater en oppervlaktewater
Lahr, Joost ; Derksen, Anja ; Wipfler, Louise ; Schans, Milou van de; Berendsen, Bjorn ; Blokland, Marco ; Dimmers, Wim ; Bolhuis, Popko ; Smidt, Rob - \ 2018
Wageningen : Wageningen Environmental Research (Wageningen Environmental Research rapport 2898) - 89
Het voorkomen, de risico’s en de mogelijkheden voor emissiereductie van humane geneesmiddelen in water krijgen de afgelopen jaren steeds meer aandacht. Naar diergeneesmiddelen gaat tot op heden minder aandacht uit dan naar humane geneesmiddelen. In 2017 is daarom onderzoek verricht naar de lotgevallen van diergeneesmiddelen in drijfmest uit de intensieve veehouderij die toegediend wordt op het land. Het onderzoek richtte zich op de kalver- en varkenshouderij en met name op het risico van uitspoeling. Voor het onderzoek werden vijf op zandgrond gelegen bedrijven in Gelderland geselecteerd uit iedere sector. Voorafgaand aan de mesttoediening werd een monster van de mest zelf genomen en op diverse tijdstippen voor en na de mestinjectie werden de bodem, het grondwater en het oppervlaktewater en sediment van kavelsloten naast de bemeste percelen bemonsterd. In al deze monsters werden de concentraties van een groot aantal antibiotica, antiparasitaire middelen, coccidiostatica en natuurlijke hormonen bepaald middels chemische analyse.
Multifunctionaliteit is the winning factor
Stremke, Sven - \ 2017
Interactive effects of oxygen, carbon dioxide and flow on photosynthesis and respiration in the scleractinian coral Galaxea fascicularis
Osinga, Ronald ; Derksen-Hooijberg, Marlous ; Wijgerde, Tim ; Verreth, Johan A.J. - \ 2017
Journal of Experimental Biology 220 (2017)12. - ISSN 0022-0949 - p. 2236 - 2242.
Carbon dioxide - Coral - Flow - Oxygen - Photosynthesis - Respiration

Rates of dark respiration and net photosynthesis were measured for six replicate clonal fragments of the stony coral Galaxea fascicularis (Linnaeus 1767), which were incubated under 12 different combinations of dissolved oxygen (20%, 100% and 150% saturation), dissolved carbon dioxide (9.5 and 19.1 μmol l-1) and water flow (1-1.6 versus 4-13 cm s-1) in a repeated measures design. Dark respiration was enhanced by increased flow and increased oxygen saturation in an interactive way, which relates to improved oxygen influx into the coral tissue. Oxygen saturation did not influence net photosynthesis: neither hypoxia nor hyperoxia affected net photosynthesis, irrespective of flow and pH, which suggests that hyperoxia does not induce high rates of photorespiration in this coral. Flow and pH had a synergistic effect on net photosynthesis: at high flow, a decrease in pH stimulated net photosynthesis by 14%. These results indicate that for this individual of G. fascicularis, increased uptake of carbon dioxide rather than increased efflux of oxygen explains the beneficial effect of water flow on photosynthesis. Rates of net photosynthesis measured in this study are among the highest ever recorded for scleractinian corals and confirm a strong scope for growth.

'Transport afstemmen op het product'
Hogeveen-van Echtelt, Esther - \ 2016
Voedingspatroon inventariseren
Derksen, M. ; Wagemakers, A. - \ 2016
Tijdschrift voor verloskundigen (2016)6. - ISSN 0378-1925 - 8 p.
Een voedingsinventarisatie kan bijdragen aan een gerichte voedingsbegeleiding op maat aan zwangere vrouwen. Marloes Derksen zocht in de literatuur naar een goede methode en naar de succesfactoren en barrières voor verloskundigen voor het geven van voedingsbegeleiding.
Screening of hot spots of emerging pollutants in soil, ground water and surface water in The Netherlands: breaking the vicious cycle.
Lahr, J. ; Laak, T. ter; Derksen, A. - \ 2015
Screening of hot spots of emerging pollutants in soil, ground water and surface water in the netherlands: breaking the vicious cycle
Lahr, J. ; Laak, T.L. ter; Derksen, A. - \ 2014
Screening van hot spots van nieuwe verontreinigingen : een pilot studie in bodem, grondwater en oppervlaktewater
Lahr, J. ; Laak, T.L. ter; Derksen, A. - \ 2014
Wageningen : Alterra (Alterra-rapport 2538) - 87
bodemverontreiniging - waterverontreiniging - verontreinigende stoffen - toxicologie - geneesmiddelen - ecologische risicoschatting - biotesten - inventarisaties - soil pollution - water pollution - pollutants - toxicology - drugs - ecological risk assessment - bioassays - inventories
Onder nieuwe verontreinigingen verstaan we stoffen die nog niet of niet volledig zijn gereguleerd en waarvan de milieurisico’s vaak onbekend zijn. Daarbij gaat het om stoffen als natuurlijke hormonen en hormoonverstorende stoffen (weekmakers, detergenten, brandvertragers, e.d.), humane geneesmiddelen, diergeneesmiddelen, nanodeeltjes en microplastics. In de ‘waterwereld’ is altijd meer aandacht besteed aan de nieuwe verontreinigingen dan binnen andere beleidsvelden. In de bodem zijn de aanwezigheid en de mogelijke risico’s grotendeels onbekend. In 2013 heeft een consortium van diverse onderzoeksinstanties en stakeholders een pilotonderzoek uitgevoerd naar de aanwezigheid en mogelijke risico’s van hormonen en geneesmiddelen in het systeem bodem - grondwater - oppervlaktewater.
Analysis of a Natural Yellow Dye: An Experiment for Analytical Organic Chemistry
Villela, A. ; Derksen, G.C.H. ; Beek, T.A. van - \ 2014
Journal of Chemical Education 91 (2014)4. - ISSN 0021-9584 - p. 566 - 569.
This experiment exposes second-year undergraduate students taking a course in analytical organic chemistry to high-performance liquid chromatography (HPLC) and quantitative analysis using the internal standard method. This is accomplished using the real-world application of natural dyes for textiles. The extracted flavonoids of the plant weld are responsible for the yellow color of the dyed wool. Dried and ground weld is extracted for dyeing wool and quantifying the plant’s three main flavonoids. The students also mimic the work of chemists investigating historical textiles by carrying out a small-scale extraction of the dyed wool. Twenty-one students carried out the experiment, and their samples were analyzed using either a traditional 5 µm-particle size HPLC column or a modern 1.8 µm-particle size ultrahigh-pressure liquid chromatography (UHPLC) column mounted in a conventional HPLC system.
Screening van hot spots van nieuwe verontreinigingen in de bodem, het grondwater en het oppervlaktewater: het doorbreken van de vicieuze cirkel
Lahr, J. ; Laak, T.L. ter; Derksen, A. ; Gylstra, R. ; Harthoorn, J. - \ 2013
Spectrophotometric comparison of the content of chlorophylls in weld (Reseda luteola)
Villela, A. ; Derksen, G.C.H. ; Zuilhof, H. ; Beek, T.A. van - \ 2011
Analytical Methods 3 (2011)6. - ISSN 1759-9660 - p. 1424 - 1427.
plant - dyes
An analytical method for the comparison of the content of chlorophylls and their structurally similar breakdown products in weld is described
Fast chromatographic separation for the quantitation of the main flavone dyes in Reseda luteola (weld)
Villela, A. ; Klift, E.J.C. van der; Mattheussens, E.S.G.M. ; Derksen, G.C.H. ; Zuilhof, H. ; Beek, T.A. van - \ 2011
Journal of Chromatography. A, Including electrophoresis and other separation methods 1218 (2011)47. - ISSN 0021-9673 - p. 8544 - 8550.
performance liquid-chromatography - diode-array detection - l. - identification - quantification - bilobalide - portugal
In the past decades, there has been a renewed interest in the use of natural dye plants for textile dyeing, e.g. Reseda luteola (weld). Its main yellow dye constituents are the flavones luteolin-7,3'-O-diglucoside, luteolin-7-O-glucoside and luteolin. The aim of this work was to develop a simple validated industrially usable quantitative method to assess the flavone content of R. luteola samples. The flavones were overnight extracted from the dried and ground aerial parts of the plant at room temperature via maceration with methanol-water 8:2. Afterwards, they were quantified through internal standardisation against chrysin by RP-HPLC-UV at 345nm. The efficiency of the one-step extraction was 95%. The limits of detection (LOD) and quantitation (LOQ) were =1ng and =3ng, respectively, providing ample sensitivity for the purpose. The precision expressed as relative standard deviation of the entire method was
Biomassa voor energie in de stadsregio Arnhem-Nijmegen : ontwikkelingen van een strategie voor biomassa uit bos, natuur en landschap
Spijker, J.H. ; Vries, E.A. de; Derksen, J.T.P. - \ 2010
Wageningen : Alterra (Alterra-rapport 2095) - 30
biomassa productie - bio-energie - landgebruik - haalbaarheidsstudies - stedelijke gebieden - landschapsbeheer - betuwe - biobased economy - biomass production - bioenergy - land use - feasibility studies - urban areas - landscape management - betuwe - biobased economy
De Stadsregio Arnhem-Nijmegen heeft behoefte aan een strategie voor de optimale inzet van biomassa uit natuur en landschap voor energie-opwekking. In dit rapport wordt inleidend het huidige aandeel duurzame energie in Nederland en de beleidsopgave uiteengezet. Daarna wordt aangegeven dat er legio kansen zijn voor oogst van biomassa uit het landschap, waarbij wel gewezen wordt op het belang van cascadering. Cascadering houdt in dat biomassa zo hoogwaardig mogelijk wordt weggezet, en dus pas in laatste instantie voor energie-opwekking. Grote kansen doen zich voor bij reststromen die nu nog als afval kunnen worden beschouwd. De houtige reststromen kunnen direct worden ingezet voor warmte-opwekking, de grazige reststromen voor vergisting. Het rapport sluit af met een aantal aanbevelingen voor de Stadsregio..
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