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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    Monitoring vooroeververdediging Oosterschelde 2015 : locaties: Zeelandbrug en Lokkersnol
    Tangelder, Martijn ; Heuvel-Greve, Martine van den; Kluijver, Maria de - \ 2016
    Yerseke : Wageningen Marine Research (Wageningen Marine Research rapport C098/16) - 86
    oeverbescherming van rivieren - dijken - steenwerk - aquatische ecosystemen - zware metalen - waterorganismen - oosterschelde - westerschelde - nederland - riverbank protection - dykes - stonework - aquatic ecosystems - heavy metals - aquatic organisms - eastern scheldt - western scheldt - netherlands
    Rijkswaterstaat heeft aan Wageningen Marine Research opdracht gegeven om in 2015 de T6-monitoring uit te voeren voor Cluster 1 locaties Zuidhoek-De Val (“Zeelandbrug”) en Cauwersinlaag (“Lokkersnol”) in de Oosterschelde. Het doel van deze monitoring is het bepalen van de samenstelling en biodiversiteit van de aanwezige levensgemeenschappen op harde en zachte substraten, en de bepaling van de gehalten aan zware metalen in mosselen en oesters. Voor locatie Lokkersnol is de monitoring alleen op levensgemeenschappen van zachte substraten gericht. De monitoring is uitgevoerd in samenwerking met Stichting Zeeschelp en TNO.
    Soortenlijst Nederlandse Noordzee
    Bos, O.G. ; Gittenberger, A. ; Boois, I.J. de; Asch, M. van; Wal, J.T. van der; Cremer, J. ; Hoorn, B. van der; Pieterse, S. ; Bakker, P.A.J. - \ 2016
    Wageningen : Wageningen Marine Research (Wageningen Marine Research rapport C125/16) - 108
    waterorganismen - soorten - soortenrijkdom - biodiversiteit - mariene ecologie - noordzee - nederland - aquatic organisms - species - species richness - biodiversity - marine ecology - north sea - netherlands
    In dit rapport is een soortenlijst opgesteld voor de Nederlandse Noordzee in opdracht van het ministerie van Economische Zaken. Er is behoefte aan een concrete lijst van inheemse en niet-inheemse Noordzeesoorten omdat het rijk direct en indirect werkt aan behoud en duurzaam gebruik van de van nature voorkomende biodiversiteit van het Nederlandse deel van de Noordzee, aan beleid over “Bouwen met Noordzeenatuur” en aan het volgen van niet-inheemse soorten (exoten) in de Noordzee.
    Environmental risk assessment of pesticides in Ethiopia : a case of surface water systems
    Teklu, B.M. - \ 2016
    Wageningen University. Promotor(en): Paul van den Brink. - Wageningen : Wageningen University - ISBN 9789462578104 - 152
    surface water - water systems - water pollution - risk assessment - ecological risk assessment - pesticides - aquatic ecology - aquatic organisms - irrigation systems - ethiopia - oppervlaktewater - watersystemen - waterverontreiniging - risicoschatting - ecologische risicoschatting - pesticiden - aquatische ecologie - waterorganismen - irrigatiesystemen - ethiopië

    The current increase in application rate and usage frequency of application of pesticides in Ethiopia pose direct risks to surface water aquatic organisms and humans and cattle using surface water as a source of drinking water in rural parts of the country. A model based risk assessment as currently being used in Europe and elsewhere in the world is tailored to the Ethiopian situation to quantify the risks. Suitability of toxicity data used as an input for risk assessment usually taken from the temperate world was checked through simple toxicity testing of Ethiopian aquatic macroinvertebrates. Subsequent monitoring activities to see the actual residue levels of pesticides in rivers and temporary ponds adjacent to extensive farming activities was also done and results compared with model prediction values. Combining all this knowledge is believed to bring the current pesticide registration system in Ethiopia one step closer to be a more reliable method, protecting non-target organisms as well as the health of humans at risk.

    Effects of silver nanoparticles and ions and interactions with first line of defense
    Georgantzopoulou, A. - \ 2015
    Wageningen University. Promotor(en): Tinka Murk, co-promotor(en): A.C. Gutleb. - Wageningen : Wageningen University - ISBN 9789462572492
    waterorganismen - toxiciteit - zilver - deeltjes - ionen - nadelige gevolgen - darmen - aquatic organisms - toxicity - silver - particles - ions - adverse effects - intestines

    Summary

    Silver nanoparticles (Ag NPs) are among the most promising groups of NPs (particles with all dimensions below 100 nm) for application in numerous consumer products due to their broad spectrum antimicrobial activities. Examples are incorporation in textiles and plastics, personal care products, water filters, food supplements etc. The extensive application and use together with the not yet fully understood properties of Ag NPs as well as the toxicity of Ag itself has raised concerns on potential impact of Ag NPs on human and environmental health.

    The research conducted within this thesis aimed at the evaluation of potential hazards of Ag NPs and identification of some key factors that determine the toxicity of Ag NPs. A tiered approach was employed using a battery of standard bioassays with model aquatic organisms, followed by the determination of sub-lethal concentrations for mechanistic endpoints, the identification of target tissues and organisms for Ag NP exposure and uptake and the integration of a proteomic tool to identify subtle changes. One of the main uptake routes for Ag NPs is through ingestion making the gastrointestinal epithelium one of the first ports of potential NP uptake and cell-particle interactions. An in vitro co-culture model incorporating a mucus layer mimicking the gastrointestinal epithelium was established for a more realistic evaluation of Ag NP potential toxicity than using intestinal epithelial cells alone. Indeed, the absence of mucus resulted in an overestimation of Ag NP toxicity. To be able to elucidate subtle changes in cellular functions and identification of particle specific effects and NP modes of action, a proteomic approach was employed. Differences and commonalities were observed between the cellular responses induced Ag NPs of different sizes and AgNO3 as a source of free Ag ions.

    As the Ag NPs are expected to reach the aquatic environment, a combination of adapted standard ecotoxicity assays with organisms of different trophic levels were used to evaluate the toxic effects Ag NPs. Synthetically produced Ag NPs of different sizes (Ag 20 and 200 nm) as well as Ag NPs synthesized by a biological method (using plant leaf extracts of Ocinum sanctum and Azadirachta indica, Ag 23 and 27 nm, respectively) were used as model particles in order to elucidate the relation between size, synthesis method, NP surface properties, ion dissolution and toxicity. Based on earlier indications of interference of another type of NPs with the multi xenobiotic resistance mechanism (MXR), a first line of defense against xenobiotics, the effects of Ag NPs on the MXR mechanism were studied as well. The MXR mechanism is present in all animals, including humans and aquatic organisms. MXR can be compromised by chemical agents that are structurally and chemically unrelated, and interference with MXR could be the basis for enhanced toxicity by contaminant mixtures. A fast in vitro cellular efflux pump inhibition assay (CEPIA) was established evaluating first the effects of contaminants commonly found in the environment. Next, an in vivo CEPIA assay was established using the juvenile D. magna model aquatic organism and the potential of the MXR modulation by Ag NPs and ionic Ag was quantified in vitro and in vivo.

    This integrated approach revealed that the size and the synthesis method are the factors affecting most the uptake and toxicity in both cells in vitro as well as in vivo in freshwater crustaceans (daphnids) and dissolution in the different media with the biologically synthesized Ag NPs being more potent compared to the conventional Ag NPs. The gastrointestinal tract is expected to be a target site for Ag NPs exposure and a co-culture of Caco-2-TC7 and HT29-MTX cells optimized and employed in the current study represents a more realistic model compared to Caco-2 monocultures. The mucus layer provides an additional protective barrier and its absence can lead to overestimation of effects in in vitro studies. Ag was detected both in the cells in co-culture, in the gut of daphnids’ as well as specific areas, seemingly developing oocytes, indicating a potential translocation of Ag NPs that could have consequences for fecundity. MXR efflux transporters were found to be modulated by Ag at low concentrations (0.18 µg/L), that are slightly lower compared to the predicted environmental concentrations.

    The extent to which the Ag ions contribute to the effects of Ag NPs depends on the size and surface properties of the Ag NPs. For the conventional, uncoated Ag NPs, the Ag release is minimal and the size is the determining factor while for biologically synthesized particles the biomolecules present due to the synthesis method and Ag release affect most the uptake and effects. The simultaneous presence of Ag ions and NPs releasing ions can lead to an exacerbation of the effects.

    The proteomic approach was successfully applied and it proved to be a useful technique in discerning subtle cellular changes in response to Ag NP exposure that would otherwise be unnoticed. Ag NPs 20 nm regulated different sets of proteins with a distinct pattern of cellular responses compared to Ag 200 nm and AgNO3, suggesting a different mode of action with effects being particle- and size-dependent.

    These results obtained during this thesis are promising for future toxicity testing of new materials using invertebrate organisms and more realistic in vitro models leading to more meaningful results and more accurate assessment of Ag NP hazards.

    P-GP efflux pump inhibition potential of common environmental contaminants determined in vitro
    Georgantzopoulou, A. ; Skoczynska, E.M. ; Berg, J.H.J. van den; Brand, W. ; Legay, S. ; Klein, S.G. ; Rietjens, I. ; Murk, A.J. - \ 2014
    Environmental Toxicology and Chemistry 33 (2014)4. - ISSN 0730-7268 - p. 804 - 813.
    multidrug-resistance transporters - flavonoid-mediated inhibition - caco-2 cell-line - aquatic organisms - multixenobiotic resistance - perfluorinated compounds - drug transport - mytilus-californianus - screening assay - great-lakes
    Across different species, cellular efflux pumps such as P-glycoprotein (P-gp; also termed multidrug resistance protein 1 [MDR1]) serve as a first line of defense by transporting toxic xenobiotics out of the cell. This mechanism is also active in aquatic organisms such as mussels, fish, and their larvae. Modulation of this resistance mechanism by chemical agents occurring in the environment could result in either higher or lower internal concentrations of toxic or endogenous compounds in cells. The aim of the present study was to explore and quantify the inhibition of the P-gp efflux pumps by several ubiquitous aquatic contaminants. The calcein-acetoxymethyl ester (calcein-AM) assay commonly used in pharmacological research was established with P-gp–overexpressing Madin–Darby canine kidney cells (MDCKII–MDR1) in a 96-well plate, avoiding extra washing, centrifugation, and lysis steps. This calcein-AM–based P-gp cellular efflux pump inhibition assay (CEPIA) was used to study the inhibition by commonly occurring environmental contaminants. Among others, the compounds pentachlorophenol, perfluorooctane sulfonate, and perfluorooctanoate strongly inhibited the P-gp–mediated efflux of calcein-AM while the chloninated alkanes did not seem to interact with the transporter. The fact that common pollutants can be potent modulators of the efflux transporters is a motive to further study whether this increases the toxicity of other contaminants present in the same matrices.
    Sediment toxicity data for benthic organisms and plant protection products : a literature review
    Deneer, J.W. ; Arts, G.H.P. ; Brock, T.C.M. - \ 2013
    Wageningen : Alterra (Alterra-report 2485) - 47
    pesticiden - zoet water - mariene gebieden - ecotoxicologie - verontreinigde sedimenten - waterorganismen - literatuuroverzichten - pesticides - fresh water - marine areas - ecotoxicology - contaminated sediments - aquatic organisms - literature reviews
    In dit rapport worden de resultaten van een literatuurstudie gepresenteerd over de gevoeligheid van sediment-bewonende (benthische) organismen voor blootstelling aan gewasbeschermingsmiddelen via het sediment. Vooral voor hydrofobe en relatief persistente gewasbeschermingsmiddelen die in oppervlaktewater terecht komen is de kans op chronische blootstelling via het sediment aanwezig.
    Koolstofnanodeeltjes hebben invloed op samenstelling waterleven
    Velzeboer, I. - \ 2013
    Nature Today (2013).
    waterorganismen - ongewervelde dieren - fauna - nanotechnologie - nadelige gevolgen - aquatic organisms - invertebrates - fauna - nanotechnology - adverse effects
    Koolstofnanodeeltjes blijken op lange termijn al bij lage concentraties effecten te hebben op het leven in het oppervlaktewater. Uit een proef onder natuurlijke veldomstandigheden komt naar voren dat de soortensamenstelling van ongewervelde waterdieren veranderde na langdurige blootstelling aan deze minuscule deeltjes. Het onderzoek is gedaan door Ilona Velzeboer van Wageningen University en onderzoeksinstituut IMARES van Wageningen UR. Zij publiceerde haar onderzoek in het toonaangevende tijdschrift Environmental Science & Technology.
    Activated carbon in sediment remediation : benefits, risks and perspectives
    Kupryianchyk, D. - \ 2013
    Wageningen University. Promotor(en): Bart Koelmans, co-promotor(en): Tim Grotenhuis. - S.l. : s.n. - ISBN 9789461734310 - 262
    waterbodems - verontreinigde sedimenten - ecotoxicologie - remediatie - actieve kool - macroinvertebraten - benthos - waterorganismen - bioaccumulatie - water bottoms - contaminated sediments - ecotoxicology - remediation - activated carbon - macroinvertebrates - benthos - aquatic organisms - bioaccumulation
    Klassieke verontreinigingen zoals hydrofobe organische verbindingen (HOCs) komen uiteindelijk vaak in waterbodems terecht. Deze waterbodems kunnen hierdoor zelf een bron van verontreiniging worden en zo een risico vormen voor aquatische organismen en voor de mens. Traditionele manieren om waterbodems te reinigen, zoals baggeren en in situ capping, zorgen voor een grote verstoring van het benthische milieu en zijn niet altijd effectief, terwijl zij wel hoge kosten met zich meebrengen. Daarom is het nodig om nieuwe methoden voor reiniging van waterbodems te ontwikkelen die makkelijker zijn, minder kosten en minder verstorend zijn dan de bestaande methoden. De afgelopen jaren is de mogelijkheid onderzocht om adsorberende materialen zoals actieve kool (AC) toe te voegen aan verontreinigde waterbodems om zo de HOC concentratie in het water te verminderen. Dit onderzoek heeft als doel om het effect van toevoegen van AC op HOC blootstelling en toxiciteitsafname voor bentische organismen en gemeenschappen beter te begrijpen, om zo het gat tussen laboratorium en veld te dichten.
    Organic photovoltaics: Potential fate and effects in the environment
    Zimmermann, Y.S. ; Schäffer, A. ; Hugi, C. ; Fent, K. ; Corvini, P.F.X. ; Lenz, M. - \ 2012
    Environment International 49 (2012). - ISSN 0160-4120 - p. 128 - 140.
    polymer solar-cells - indium-tin-oxide - fullerene water suspensions - life-cycle analysis - polyethylene terephthalate - engineered nanoparticles - biodegradable polymers - aquatic organisms - manufactured nanoparticles - degradation mechanisms
    In times of dwindling fossil fuels it is particularly crucial to develop novel “green” technologies in order to cover the increasing worldwide demand for energy. Organic photovoltaic solar cells (OPVs) are promising as a renewable energy source due to low energy requirement for production, low resource extraction, and no emission of greenhouse gasses during use. In contrast to silicium-based solar cells, OPVs offer the advantages of light-weight, semi-transparency and mechanical flexibility. As to a possible forthcoming large-scale production, the environmental impact of such OPVs should be assessed and compared to currently best available technologies. For the first time, this review compiles the existing knowledge and identifies gaps regarding the environmental impact of such OPVs in a systematic manner. In this regard, we discuss the components of a typical OPV layer by layer. We discuss the probability of enhanced release of OPV-borne components into the environment during use-phase (e.g. UV- and biodegradation) and end-of-life phase (e.g. incineration and waste disposal). For this purpose, we compiled available data on bioavailability, bioaccumulation, biodegradation, and ecotoxicity. Whereas considerable research has already been carried out concerning the ecotoxicity of certain OPV components (e.g. nanoparticles and fullerenes), others have not been investigated at all so far. In conclusion, there is a general lack of information about fate, behavior as well as potential ecotoxicity of most of the main OPV components and their degradation/transformation products. So far, there is no evidence for a worrying threat coming from OPVs, but since at present, no policy and procedures regarding recycling of OPVs are in action, in particular improper disposal upon end-of-life might result in an adverse effect of OPVs in the environment when applied in large-scale.
    Scenarios for exposure of aquatic organisms to plant protection products in the Netherlands : part 1: Field crops and downward spraying
    Tiktak, A. ; Adriaanse, P.I. ; Boesten, J.J.T.I. ; Griethuysen, C. van; Horst, M.M.S. ter; Linders, J.B.H.J. ; Linden, A.M.A. van der; Zande, J.C. van de - \ 2012
    Bilthoven : National Institute for Public Health and the Environment (RIVM report ) - 129
    aquatische ecologie - waterorganismen - ecotoxicologie - pesticiden - waterverontreiniging - drift - modellen - aquatic ecology - aquatic organisms - ecotoxicology - pesticides - water pollution - drift - models
    In the current Dutch authorisation procedure for calculating the exposure of surface water organisms to plant protection products, drift deposition is considered to be the only source for exposure of surface water organisms. Although drift can still be considered the most important source, atmospheric deposition and drainage may constitute important sources as well. Therefore, RIVM, PBL, Wageningen UR and the Board for the authorisation of plant protection products and biocides have derived a new procedure in which these two potential sources are included. The new procedure, described in this report, is restricted to downward spray applications in field crops
    Global rivers warming up: impacts on cooling water use in the energy sector and freshwater ecosystems
    Vliet, M.T.H. van - \ 2012
    Wageningen University. Promotor(en): Pavel Kabat, co-promotor(en): Fulco Ludwig. - S.l. : s.n. - ISBN 9789461734242 - 196
    klimaatverandering - oppervlaktewater - zoetwaterecologie - watertemperatuur - rivierafvoer - koelwater - waterorganismen - nadelige gevolgen - climatic change - surface water - freshwater ecology - water temperature - stream flow - cooling water - aquatic organisms - adverse effects - cum laude
    cum laude graduation (with distinction)
    Inhibition of cellular efflux pumps involved in multi xenobiotic resistance (MXR) in echinoid larvae as a possible mode of action for increased ecotoxicological risk of mixtures
    Drs Anselmo, H.M.R. ; Berg, J.H.J. van den; Rietjens, I. ; Murk, A.J. - \ 2012
    Ecotoxicology 21 (2012)8. - ISSN 0963-9292 - p. 2276 - 2287.
    multixenobiotic defense-mechanism - mussel mytilus-galloprovincialis - urchin psammechinus-miliaris - p-glycoprotein - aquatic organisms - pluronic p85 - drug efflux - marine mussel - bivalve gills - in-vitro
    In marine organisms the multi xenobiotic resistance (MXR) mechanism via e.g. P-glycoprotein (P-gp) and multidrug resistance-associated protein (MRP) is an important first line of defense against contaminants by pumping contaminants out of the cells. If compounds would impair the MXR mechanism, this could result in increased intracellular levels of other compounds, thereby potentiating their toxicity. A calcein-AM based larval cellular efflux pump inhibition assay (CEPIA) was developed for echinoid (Psammechinus miliaris) larvae and applied for several contaminants. The larval CEPIA revealed that triclosan (TCS) and the nanoparticles P-85® (P-85) were 124 and 155× more potent inhibitors (IC50 0.5 ± 0.05 and 0.4 ± 0.1 µM, respectively) of efflux pumps than the model inhibitor Verapamil (VER). PFOS (heptadecafluorooctane sulfonic acid) and pentachlorophenol also were more potent than VER, 24 and 5×, respectively. Bisphenol A and o,p'-dichlorodiphenyltrichloroethane (o,p'-DDT) inhibited efflux pumps with a potency 3× greater than VER. In a 48 h early life stage bioassay with P. miliaris, exposure to a non-lethal concentration of the inhibitors TCS, VER, the model MRP inhibitor MK-571, the nanoparticles P-85 and the model P-gp inhibitor PSC-833, increased the toxicity of the toxic model substrate for efflux pumps vinblastine by a factor of 2, 4, 4, 8 and 16, respectively. Our findings show that several contaminants accumulating in the marine environment inhibit cellular efflux pumps, which could potentiate toxic effects of efflux pumps substrates
    Mogelijke effecten van geneesmiddelen in effluent op aquatische organismen
    Roessink, I. ; Fait, G. ; Belgers, J.D.M. ; Boerwinkel, M.C. - \ 2012
    Wageningen : Alterra, Wageningen-UR (Alterra-report 2338) - 46
    geneesmiddelen - waterorganismen - afvoerwater - milieueffect - waterverontreiniging - experimentele ecosystemen - drugs - aquatic organisms - effluents - environmental impact - water pollution - experimental ecosystems
    Dit onderzoek is uitgevoerd in opdracht van het waterschap Regge en Dinkel. In dit onderzoek wordt met de beschikbare internationale literatuur en een experimentele studie onderzocht of er mogelijke effecten op populaties van aquatische organismen te verwachten zijn van geneesmiddelen in effluent van waterzuiveringsinstallaties. De gevonden resultaten in de testsystemen laten zien dat met uitzondering van Sulfamethoxazole en Bisphenol A de geneesmiddelen in het testmedium onder de gebruikte testcondities niet persistent zijn. Er kon geen negatieve impact van het geteste effluent op populaties van watervlooien, waterpissebedden, wormen, slakken en waterplanten aangetoond worden. Het effluent had echter wel een stimulerend effect op de populatiedichtheden van deze waterorganismen. Dit werd waarschijnlijk veroorzaakt door de hoge voedselbeschikbaarheid (nutriënten; organisch materiaal) in het effluent.
    Toxic concentrations in fish early life stages peak at a critical moment
    Foekema, E.M. ; Fischer, A. ; Lopez Parron, M. ; Kwadijk, C. ; Vries, P. de; Murk, A.J. - \ 2012
    Environmental Toxicology and Chemistry 31 (2012)6. - ISSN 0730-7268 - p. 1381 - 1390.
    medaka oryzias-latipes - organochlorine compounds - aquatic organisms - maternal transfer - risk-assessment - pcb congeners - exposure - accumulation - substances - bioaccumulation
    During the development of an embryo into a juvenile, the physiology and behavior of a fish change greatly, affecting exposure to and uptake of environmental pollutants. Based on experimental data with sole (Solea solea), an existing bioaccumulation model was adapted and validated to calculate the development of concentrations of persistent organic pollutants in the tissue of developing fish. Simulation revealed that toxic tissue concentrations of pollutants with log octanol–water partition ratio (KOW)¿>¿5 peak at the moment when the larvae become free-feeding, when the lipid reserves are depleted. This may explain the delayed effects observed in fish early-life-stage experiments with exposed eggs. In the field, eggs can be exposed through maternal transfer to adult pollutant tissue concentrations, which will increase in the larva to peak tissue concentrations, exceeding those of the adult fish. The results demonstrate the risk of underestimating the effects of lipophilic persistent organic pollutants with log KOW¿>¿5 in short-term, early-life-stage fish tests and underscore the importance of maternal transfer as an exposure route in the field situation.
    Een frisse blik op warmer water : over de invloed van klimaatverandering op de aquatische ecologie en hoe je de negatieve effecten kunt tegengaan
    Kosten, S. ; Schep, S. ; Weeren, B.J. van - \ 2011
    Amersfoort : Stowa (STOWA -rapport nr. 2011-20) - ISBN 9789057735240 - 132
    aquatische ecologie - klimaatverandering - waterbeheer - neerslag - temperatuur - waterorganismen - biogeochemie - zoetwaterecologie - nederland - aquatic ecology - climatic change - water management - precipitation - temperature - aquatic organisms - biogeochemistry - freshwater ecology - netherlands
    Dit rapport bundelt de belangrijkste kennis over mogelijke invloeden van klimaatverandering op zoete aquatische ecosystemen en geeft waterbeheerders handvatten hoe ze rekening kunnen houden met de effecten van klimaatverandering bij het uitvoeren van hun taken. Met de kennis uit dit rappport kunnen waterbeheerders een optimaal (effectief) pakket aan maatregelen samenstellen om de waterkwaliteit te verbeteren. Daarnaast kunnen ze bij inrichting en beheer goed rekening houden met de effecten van klimaatverandering. Het rapport ondersteunt daarmee het opstellen van de tweede generatie stroomgebiedbeheersplannen, die in 2015 gereed moeten zijn.
    Hair 2010 Documentation: Calculating risk indicators related to agricultural use of pesticides within the European Union
    Kruijne, R. ; Deneer, J.W. ; Lahr, J. ; Vlaming, J. - \ 2011
    Wageningen : Alterra (Alterra-report 2113.1) - 205
    pesticiden - risicofactoren - berekening - databanken - modellen - waterorganismen - bodem - grondwater - vogels - zoogdieren - beleid - gewassen - europese unie - pesticides - risk factors - calculation - databases - models - aquatic organisms - soil - groundwater - birds - mammals - policy - crops - european union
    The HAIR instrument calculates risk indicators related to the agricultural use of pesticides in EU Member States. HAIR combines databases and models for calculating potential environmental environmental effects expressed by the exposure toxicity ratio.
    Aggregation of ecological indicators for mapping aquatic nature quality : overview of existing methods and case studies
    Knotters, M. ; Lahr, J. ; Oosten-Siedlecka, A.M. van; Verdonschot, P.F.M. - \ 2010
    Wageningen : Wettelijke Onderzoekstaken Natuur & Milieu (WOt-werkdocument 209) - 44
    waterorganismen - biologische indicatoren - oppervlaktewater - stroomgebieden - natuurwaarde - ruimtelijke modellen - correlatie - zoetwaterecologie - nederland - aquatic organisms - biological indicators - surface water - watersheds - natural value - spatial models - correlation - freshwater ecology - netherlands
    Indicators for aquatic nature quality are calculated using ecological monitoring data from individual sampling stations. For reporting purposes, these results need to be aggregated and scaled up to higher levels (catchment area, country). This report provides an overview of different existing spatial aggregation methods for this purpose, including an evaluation of their suitability for aquatic ecological indicators. So-called „model-based„ methods, consisting of some sort of „kriging¿ step followed by calculation of the arithmetic mean, appeared to be the most appropriate. Application of these methods to multimetric indicators of aquatic macroinvertebrates in two Dutch subcatchment areas confirmed their suitability. However, the methods that were used were based on aggregation (using kriging) over Euclidian (straight), distances. It is recommended to conduct further research on the suitability of interpolation through stream networks, i.e., through the waterways themselves.
    Graadmeters aquatische natuur : analyse gegevenskwaliteit Limnodata
    Verdonschot, P.F.M. ; Oosten-Siedlecka, A.M. van - \ 2010
    Wageningen : Wettelijke Onderzoekstaken Natuur & Milieu (WOt-werkdocument 210) - 106
    macrofauna - gegevens verzamelen - natuurwaarde - waterorganismen - monitoring - nederland - waterschappen - oppervlaktewater - macrofauna - data collection - natural value - aquatic organisms - monitoring - netherlands - polder boards - surface water
    Onderzoek is uitgevoerd om een beeld te verkrijgen van de geschiktheid van gegevens in de Limnodata om een methode te ontwikkelen voor het waarderen van aquatische natuurkwaliteit en om bij te dragen aan de ontwikkeling van het standaardiseren van gegevensverzameling en kwaliteitscontrole aan de poort van de Limnodata. Hiertoe is een vergelijking uitgevoerd van de macrofaunagegevens die aanwezig zijn in de Limnodata Neerlandica met de oorspronkelijke bronbestanden voor macrofauna die aanwezig zijn bij de waterschappen (i.c. Hoogheemraadschap Hollands Noorderkwartier, Waterschap Velt & Vecht, Waterschap Regge & Dinkel en Wetterskip Fryslan). De vergelijking leverde grote verschillen op in locaties, monsters en monsterinhoud, zoals omschrijving, standaardisatie en bemonsteringsmethode. Het document geeft een nadere duiding van de aard van deze verschillen. De Limnodata bleek slechts 42% van de monsters van het Hoogheemraadschap Hollands Noorderkwartier, 34% van de monsters van Velt & Vecht, 43% van de monsters van Regge & Dinkel en 46% van de monsters van Wetterskip Fryslan correct te hebben overgenomen. In deze percentages zijn de ontbrekende locaties nog niet meegenomen. Omdat de onjuistheden geen patroon bezitten en de verschillen voldoende groot zijn, zullen ze de resultaten van vervolganalyses in belangrijke mate beïnvloeden. Daarom wordt het gebruik van de Limnodata niet aanbevolen voor doelen zoals Natuurverkeningen en andere toepassingen.
    Quick scan kosteneffectiviteitanalyse aquatische natuur
    Linderhof, V.G.M. ; Leneman, H. - \ 2010
    Wageningen : Wettelijke Onderzoekstaken Natuur & Milieu (WOT Natuur & Milieu) (WOt-werkdocument 211) - 54
    waterorganismen - biodiversiteit - waterkwaliteit - natuurwaarde - oppervlaktewater - cost effective analysis - nederland - aquatic organisms - biodiversity - water quality - natural value - surface water - cost effectiveness analysis - netherlands
    Dit werkdocument geeft inzicht in de wijze waarop de kosteneffectiviteit van de biodiversiteit in aquatische natuur kan worden bepaald. Via literatuurstudie en gesprekken met experts is bestaande en ook de nog ontbrekende kennis om een kosteneffectiviteitanalyse voor aquatische natuur uit te voeren op een rij gezet. Voor de komende natuurverkenningen is het bepalen van de kosteneffectiviteit van beleid voor aquatische natuur op korte termijn haalbaar op het niveau van waterlichamen en voor het grootste deel van de Nederlandse wateren.
    Is there chaos out there? : analysis of complex dynamics in plankton communities
    Benincà, E. - \ 2010
    Wageningen University. Promotor(en): Marten Scheffer; J. Huisman, co-promotor(en): K. Jöhnk; Egbert van Nes. - [S.l. : S.n. - ISBN 9789085858126 - 169
    plankton - waterorganismen - veranderingen in de bevolking - populatiedichtheid - populatiedynamica - chaos - wiskundige modellen - populatiebiologie - plankton - aquatic organisms - population change - population density - population dynamics - chaos - mathematical models - population biology
    Species often show irregular fluctuations in their population abundances. Traditionally, ecologists have thought that external processes (e.g., variability in weather conditions) are the main drivers of these ups and downs. However, recent theoretical work suggests that fluctuations in natural populations may also be driven by internal mechanisms (e.g., the interplay between species). In this thesis I use a combination of time series analysis and modeling to provide more insight into the question to which extent such internally generated chaos might drive the population dynamics of plankton communities under controlled as well as natural conditions. In short, this thesis demonstrates in theory and experiment that species in plankton communities may rise and fall forever in a chaotic way. This result challenges the traditional view that nature is at equilibrium and that only externally driven processes may disturb this equilibrium.
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