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1. Greenhouse data experiment drip irrigation 2016

Author

Wipfler, E.L., Beltman, W.H.J., Boesten, J.J.T.I., Hoogsteen, M.J.J., van der Linden, A.M.A., va Os, E.A., van der Staaij, M., Swinkels, G.L.A.M., Wipfler, E.L., Beltman, W.H.J., Boesten, J.J.T.I., Hoogsteen, M.J.J., van der Linden, A.M.A., va Os, E.A., van der Staaij, M., and Swinkels, G.L.A.M.

Abstract

The 'Greenhouse data experiment drip irrigation 2016' file contains data gathered during the experiment as described in Wipfler et al. (2020), Testing of the Greenhouse Emission Model for application of plant protection products via drip irrigation. WENR report 3004. Climate parameters were collected from the Lets Grow database, these parameters include water supply, drain water flow, external rainwater intake, radiation outside (W/m2), realized temperature and relative humidity in greenhouse compartment., The 'Greenhouse data experiment drip irrigation 2016' file contains data gathered during the experiment as described in Wipfler et al. (2020), Testing of the Greenhouse Emission Model for application of plant protection products via drip irrigation. WENR report 3004. Climate parameters were collected from the Lets Grow database, these parameters include water supply, drain water flow, external rainwater intake, radiation outside (W/m2), realized temperature and relative humidity in greenhouse compartment.

Published
2023

2. Manual for the TOXSWA SedDis tool v1 : Testing segmentation of the sediment layer in TOXSWA

Author

Thouément, H.A.A., Beltman, W.H.J., Braakhekke, M.C., Thouément, H.A.A., Beltman, W.H.J., and Braakhekke, M.C.

Abstract

The SedDis tool is a decision-support tool for selecting the optimal segmentation for the sediment in TOXSWA simulations. The TOXSWA model is used to calculate exposure concentrations of pesticides and their metabolites in watercourses and ponds. For the parameterization of the water body, its water layer and sediment layer need to be spatially discretized. For the sediment layer, the size of the grid (segmentation) is crucial. Selecting the optimal segmentation ensures that simulated concentrations are calculated with a satisfying accuracy when simulating the transport of strongly sorbing compounds within the TOXSWA model. The theoretical background and methodologyfor the SedDis tool is described. The procedure for using the SedDis tool is provided. Instructions for running the tool with an example (selecting standard or fine segmentation for a given scenario) are given., De SedDis tool is een beslissingsondersteunend instrument voor het selecteren van de optimale segementatie voor het sediment in TOXSWA-simulaties. Het TOXSWA-model wordt gebruikt om blootstellingsconcentraties van pesticiden en hun metabolieten in vijvers en waterlopen te berekenen. Voor de parameterisatie van het waterlichaam, worden de waterlaag en sedimentlaag ruimtelijk in segmenten verdeeld. Voor het sediment is desegmentatie cruciaal. Het selecteren van de optimale segmentatie zorgt ervoor dat de blootstellingsconcentraties met een acceptabele nauwkeurigheid worden berekend voor sterk adsorberende stoffen. De theoretische achtergrond van de methode wordt beschreven, en ook de installatie en procedure voor gebruik van de tool. Instructies voor het gebruik van de tool met een voorbeeld – selectie van een standaard segmentatie of fijnere segmentatie voor een gegeven scenario – worden gegeven.

Published
2022

3. Modeling effectiveness of two runoff mitigation measures in the Netherlands

Author

Heinen, M., Beltman, W.H.J., Massop, H.T.L., Groenendijk, P., Dik, P.E., Sur, Robin, Heinen, M., Beltman, W.H.J., Massop, H.T.L., Groenendijk, P., Dik, P.E., and Sur, Robin

Abstract

Rainfall that exceeds the soil's maximum infiltration rate is prone to runoff, and the excess rainfall will flow toward open water systems. Nutrients, pesticides or other contaminants may be transported along with this overland flow, thus contaminating surface waters. There are various measures that can be implemented to prevent or reduce runoff, which involve either improving the soil's infiltration capacity or temporarily storing more water at the field scale. The aim of this study was to determine the effectiveness of two mitigation measures, i.e., micro-dams and edge-of-field trenches, in reducing the total number of runoff events and the runoff volume for specific rainfall events. For this purpose, numerical simulations were performed with a deterministic soil–water–atmosphere–plant model for reference situations and for situations involving either of the two mitigation measures. The mitigation measures are implemented as a change in the ponding threshold height above which the model predicts runoff. For this purpose, we considered several soil / groundwater level / crop / intrinsic field soil surface storage situations that are common in the Netherlands. For ridge-furrow cropping systems, micro-dams are more effective than edge-of-field trenches. Depending on the soil type (excluding sand), the minimum effectiveness is 70% and may be >90% in specific situations. For the edge-of-field trench, the reduction in runoff events was mostly in the 24–35% range, while the effectiveness for the runoff volume for a rainfall event that typically occurs once per year was in the 13–48% range (excluding sand). Due to the relatively high hydraulic conductivity at saturation for the sandy soils, runoff was simulated in only a few cases for these soils. The effectiveness was evidently dependent on intrinsic field soil surface storage and soil types, varied slightly between crop types and was very similar across the groundwater level classes considered.

Published
2022

4. Volatilization from surface water bodies in the pesticide model TOXSWA : implementation report

Author

Beltman, W.H.J., Adriaanse, P.I., Beltman, W.H.J., and Adriaanse, P.I.

Abstract

The TOXSWA model has been extended with the functionality to simulate pesticide volatilization from open water surfaces on the basis of a micro-meteorological framework. TOXSWA simulates the fate of pesticides in water bodies to calculate exposure concentrations for aquatic organisms or sediment-dwelling organisms as part of the aquatic risk assessment in the regulatory process of pesticides at EU level and in The Netherlands. Volatilization of pesticides from water to air has been described in the TOXSWA model based on the Liss and Slater method. This report describes the implementation in TOXSWA of an improved methodology to describe volatilization of pesticides from small water bodies. Hourly meteorological data on wind speed and air temperature are used to calculate the rate of volatilization of the pesticide from the water layer., Het TOXSWA model beschrijft het gedrag van gewasbeschermingsmiddelen in het water-sediment systeem in kleine oppervlaktewateren. Het berekent hier blootstellingsconcentraties voor water- en sedimentorganismen, die in de aquatische toelatingsprocedure in Nederland en de EU worden gebruikt. Het model is nu verbeterd door de toevoeging van een functionaliteit voor vervluchtiging op basis van een micro- meteorologische benadering. De vervluchtiging wordt bepaald door het concentratie verschil op het atmosfeer-water grensvlak en hangt verder af van twee atmosferische weerstanden en een aquatische weerstand tegen transport van het gewasbeschermingsmiddel in de gasfase. De parameterisatie gebruikt uurlijkse waarden voor windsnelheid en temperatuur in water en in atmosfeer. Vervluchtiging van gewasbeschermingsmiddel is een belangrijk proces voor de blootstellingsconcentratieberekening. Vooral in stilstaand oppervlaktewater of water met lage stroomsnelheden kan de combinatie van langzame vervluchtiging, lage omzetting en herhaald toepassen leiden tot accumulatie van het middel in water en/of sediment en mogelijk verhoogde risico’s voor de organismen.

Published
2022

8. Testing of the Greenhouse Emission Model for application of plant protection products via drip irrigation in soilless cultivation

Author

Wipfler, E.L., Beltman, W.H.J., Boesten, J.J.T.I., Hoogsteen, M.J.J., van der Linden, A.M.A., va Os, E.A., van der Staaij, M., Swinkels, G.L.A.M., Wipfler, E.L., Beltman, W.H.J., Boesten, J.J.T.I., Hoogsteen, M.J.J., van der Linden, A.M.A., va Os, E.A., van der Staaij, M., and Swinkels, G.L.A.M.

Abstract

An experiment was conducted to test the Greenhouse Emission Model (GEM) performance. The model simulates fate of plant protection products in soilless systems for a various combinations of application types, substrate and crop types in Dutch greenhouses. Pymetrozine and imidaclorid are applied withthe nutrient solution in sweet pepper growing on stone-wool. Measured and simulated concentrations were compared for (i) simulations with experimentally derived water flows, (ii) simulated water flows based on weather conditions and based on computer settings of the automatic control system and (iii) a predefined scenario in GEM3.3.2 for sweet pepper. GEM is able to simulate water flows well, when these flows are based on weather conditions and computer settings. Also, the concentrations in the mixing tank were simulated well. Simulated concentrations in the used water reservoir were higher than measured concentration. The model performance improves when the cultivation compartment is simulated with two reservoirs instead of one, with the rationale that no complete mixing occurs in the cultivation compartment. The effect of plant uptake and degradation could not be assessed. The concentration in the recirculation water in greenhouse is sensitive to the volumes of the various reservoirs in the greenhouse system. It is recommended to update the reservoir volumes according to the latest insight on commercial greenhouse systems.

Published
2020

9. User manual for FOCUSSPIN version 3.3

Author

van Kraalingen, D., van den Berg, F., Wipfler, E.L., Beltman, W.H.J., ter Horst, M.M.S., te Roller, J.A., van Kraalingen, D., van den Berg, F., Wipfler, E.L., Beltman, W.H.J., ter Horst, M.M.S., and te Roller, J.A.

Abstract

In the EU and Dutch national registration procedures for plant protection products, fate models and scenarios are being used to assess the environmental risks of these products. For each model application, data on the physico-chemical properties of the substances are required. The software tool SPIN has been developed to store substance properties in a common database that can be accessed by the different model applications. This facilitates the use of these model applications for a specific substance. This user manual describes the use of FOCUSSPIN version 3.3, that can be used in combination with the EU FOCUS models (leaching to groundwater and exposure in surface water). FOCUSSPIN version 3.3. can also be used in combination with the new versions of national exposure assessment tools GeoPEARL (leaching to groundwater), DROPLET (drinking water) as well as the current version of GEM 3.3.2 (emission from greenhouses)., In de Europese en Nederlandse nationale toelatingsprocedure voor gewasbeschermingsmiddelen worden modellen en scenario’s gebruikt om de milieurisico’s van deze producten te beoordelen. Voor elke modeltoepassing zijn gegevens over de fysisch-chemische eigenschappen nodig. De softwaretool SPIN is ontwikkeld voor de opslag van stofeigenschappen in een gedeelde database, die door de verschillende modeltoepassingen gebruikt kan worden. Dat vergemakkelijkt het gebruik van deze modeltoepassingen voor een specifieke stof. Deze gebruikershandleiding beschrijft de toepassing van FOCUSSPIN versie 3.3, die gebruikt kan worden in combinatie met de EU FOCUS-modellen (uitspoeling naar grondwater en blootstelling in oppervlaktewater). FOCUSSPIN versie 3.3 kan ook gebruikt worden in combinatie met de nieuwe versies van de nationale blootstellingsinstrumenten GeoPEARL (uitspoeling naar grondwater), DROPLET (drinkwater) en de huidige versie van GEM 3.3.2 (emissie vanuit kassen).

Published
2020

10. Analytical modeling of effects of application frequency on pesticide concentrations in wells

Author

Beltman, W.H.J., Boesten, J.J.T.I., Zee, S.E.A.T.M. van der, and Quist, J.J.

Subjects
Hydrogeology -- Models -- Environmental aspects, Pesticides -- Environmental aspects -- Models, Pollution -- Models -- Environmental aspects, Water, Underground -- Models -- Environmental aspects, Earth sciences, Models, Environmental aspects
Abstract

Introduction Agricultural pesticide use is one of the main diffuse sources of ground-water contamination that threatens public water supply based on ground-water extraction. Pesticide concentrations up to 100 mg [m.sup.-3] [...]

Published
1996

14. External scientific report: Data collection for the estimation of ecological data (specific focal species, time spent in treated areas collecting food, composition of diet), residue level and residue decline on food items to be used in the risk assessment for birds and mammals

Author

Lahr, J., Kramer, Wolfgang, Mazerolles, Vanessa, Poulsen, Veronique, Jölli, Daniela, Müller, Marc, McVey, Emily, Wassenberg, J., Derkx, M.P.M., Brouwer, J.H.D., Deneer, J.W., Beltman, W.H.J., Lammertsma, D.R., Jansman, H.A.H., and Buij, R.

Subjects
Environmental Risk Assessment, Dierecologie, Life Science, Animal Ecology, Library Collections, Library Research and Education Support, Frontoffice
Abstract

The study described in this report was conducted with the aim of developing an unified database of ecological data and residue data to be used for the risk assessment of plant protection products for birds and mammals. The main sources of data were the information submitted in the context of approval of active substances and authorization of products and and additional information retrieved through a systematic literature review. The data were screened and organised in three Excel databases, one for birds, one for mammals and one for residue studies. The ecological information for birds and mammal risk assessment consisted of data that is used for the determination of focal species, estimation of the proportion of an animal's daily diet obtained in a treated habitat (PT) and assessment of the composition of the diet obtained from a treated area (PD). The information gathered on residues focussed on (initial) residue levels after treatment and on residue decline (the reported half‐life or DT50 and the DT90)

Published
2018

15. Manual for FOCUS_TOXSWA v5.5.3 and for expert use of TOXSWA kernel v3.3 : user’s guide version 5

Author

Beltman, W.H.J., ter Horst, M.M.S., Adriaanse, P.I., de Jong, A., Beltman, W.H.J., ter Horst, M.M.S., Adriaanse, P.I., and de Jong, A.

Abstract

The FOCUS_TOXSWA model calculates exposure concentrations of pesticides and their metabolites in watercourses and ponds, of the so-called FOCUS surface water scenarios. These concentrations are used in the pesticide registration procedure at EU level. The model concepts of TOXSWA are described briefly. The procedure for using the TOXSWA kernel (i.e. expert use) and related input files and output files are described. Concerning FOCUS_TOXSWA, the use of the graphical user interface to access the input and output is described. Input data are stored in a database. Pesticide entries resulting from drainage or runoff/erosion are accessed from separate files generated by FOCUS_MACRO and FOCUS_PRZM. Substance properties are accessed from the SPIN tool/database. Instructions for simulating a water-sediment study and a multi-year run are given.

Published
2018

18. Including multistress in the risk assessment of plant protection products : current state of knowledge, based on a literature review and an evaluation of tank mixture applications in a spraying schedule for strawberries

Author

Arts, G.H.P., Beltman, W.H.J., Holterman, H.J., van Vliet, P.J.M., Wipfler, E.L., van de Zande, J.C., Arts, G.H.P., Beltman, W.H.J., Holterman, H.J., van Vliet, P.J.M., Wipfler, E.L., and van de Zande, J.C.

Abstract

Fluctuations of input and output prices are major reasons causing volatile gross margins in livestock production. There are large historic differences in the period 2001-2015 between the dairy sector and fattening pig sector in volatility. Relatively large fluctuations in gross margins were observed in the fattening pig sector (median coefficient of variation (CV) value of 32%). In the dairy sector gross margin between years was more smooth (median CV values of 12%), but projections are that after the gradual reduction of EU milk price support and following the abolishment of the EU milk quota system dairy farmers will become more exposed to the world market for dairy products and are becoming more vulnerable to (supply and demand) shocks affecting world dairy markets and prices.

Published
2017

19. Temperature in water and sediment in the pesticide model TOXSWA : implementation report

Author

Beltman, W.H.J., Adriaanse, P.I., Jacobs, C.M.J., Mulder, H.M., Beltman, W.H.J., Adriaanse, P.I., Jacobs, C.M.J., and Mulder, H.M.

Abstract

TOXSWA simuleert het gedrag van stoffen in oppervlaktewater om blootstellingsconcentratie te berekenen voor organismen die in water of sediment leven, als onderdeel van de aquatische risicobeoordeling van gewasbeschermingsmiddelen (GBM). Het vernieuwde concept voor de beschrijving van de temperatuur in het TOXSWA model werd getest aan de hand van een bestaande implementatie van het 1D bulk model.

Published
2017

20. Hydrolysis and biotic transformation in water in the pesticide model : Implementation report

Author

ter Horst, M.M.S., Beltman, W.H.J., Adriaanse, P.I., Mulder, H.M., ter Horst, M.M.S., Beltman, W.H.J., Adriaanse, P.I., and Mulder, H.M.

Abstract

The TOXSWA model has been extended with the functionality to simulate hydrolysis and biotic transformation in water. TOXSWA simulates the fate of pesticides in water bodies to calculate exposure calculations for aquatic organisms or sediment-dwelling organisms as part of the aquatic risk assessment of pesticides. Hydrolysis and biotic transformation are modelled as first-order processes, occuring in the water phase only. The hydrolysis transformation rates are considered to be dependent on both pH and temperature. The biotic transformation rate is considered to be temperature-dependent only.

Published
2017

21. Evaluation of the Dutch leaching decision tree with the substances bentazone, MCPA and mecoprop

Author

van der Linden, A.M.A., Beltman, W.H.J., Boesten, J.J.T.I., and Pol, J.W.

Subjects
Environmental Risk Assessment, water pollution, sorption, beslissingsmodellen, drinking water, degradatie, risk assessment, pesticides, waterkwaliteit, water quality, sorptie, decision models, risicoschatting, leaching, mcpa, bentazon, pesticiden, groundwater, grondwater, uitspoelen, bentazone, drinkwater, waterverontreiniging, degradation
Abstract

Sinds 2004 wordt een beslismodel (beslisboom) gebruikt om te beoordelen in welke mate een gewasbeschermingsmiddel uitspoelt naar het grondwater. Uit een evaluatie van het RIVM, het College voor de toelating van gewasbeschermingsmiddelen en biociden (Ctgb) en onderzoekinstituut Alterra blijkt dat de beslisboom goed werkt en state of the art is. Wel laten de stofgegevens waarmee wordt gerekend te wensen over. Om de kwaliteit van het grondwater te waarborgen moeten deze gegevens zorgvuldiger worden afgeleid.

Published
2015

22. SWASH Manual 5.3 : user’s guide version 5

Author

van den Berg, F., Beltman, W.H.J., Adriaanse, P.I., de Jong, A., and te Roller, J.A.

Subjects
Environmental Risk Assessment, Earth Observation and Environmental Informatics, ditches, pesticides, sloten, waterkwaliteit, water quality, models, monitoring, pesticiden, WOT Natuur & Milieu, Aardobservatie en omgevingsinformatica, drainage, modellen
Abstract

SWASH (Surface WAter Scenarios Help) assists the user in calculating pesticide exposure concentration in the EU FOCUS surface water scenarios. It is part of the exposure calculation procedure, being part of the obligatory evaluation procedure to place an active substance on List 1 according to EU Directive 91/414/EEC. SWASH encompasses: (i) FOCUS Drift Calculator, calculating pesticide entries through spray drift deposition, (ii) PRZM-3, calculating pesticide entries through run-off, (iii) MACRO, calculating pesticide entries through drainage and (iv) TOXSWA, calculating the behaviour of pesticides in small surface waters. It is linked to SPIN, a pesticide properties tool, and prepares input for the PRZM, MACRO and TOXSWA models. Via the SWASH shell the user can enter the shells of the other models to perform the PRZM or MACRO model runs needed to assess the fate of the substance in he FOCUS water body systems using TOXSWA.

Published
2015

24. Surface WAter Scenario Help (SWASH) version 5.3 : technical description

Author

te Roller, J.A., van den Berg, F., Adriaanse, P.I., de Jong, A., and Beltman, W.H.J.

Subjects
Environmental Risk Assessment, Earth Observation and Environmental Informatics, databases, ditches, emission reduction, pesticides, sloten, waterkwaliteit, water quality, emissiereductie, models, pesticiden, WOT Natuur & Milieu, Aardobservatie en omgevingsinformatica, databanken, modellen
Abstract

The user-friendly shell SWASH, acronym for Surface WAter Scenarios Help, assists the user in calculating pesticide exposure concentrations in the EU FOCUS surface water scenarios. SWASH encompasses five separate tools and models: (i) FOCUS Drift Calculator, calculating pesticide entries through spray drift deposition, (ii) PRZM-3, calculating pesticide entries through run-off, (iii) MACRO, calculating pesticide entries through drainage, (iv) TOXSWA, calculating the behaviour of pesticides in small surface waters, and (v) SPIN is a central database for storage and editing of pesticide properties. The SWASH database contains information on projects and runs created by the user. This report gives a detailed description of the necessary flow of data between the various models, to make them communicate smoothly with each other. It also specifies the installation requirements for the MACRO, PRZM and TOXSWA models. The MACRO model uses an MS-Access database to store its substance and run information, while PRZM makes use of separate data files. TOXSWA uses the central SWASH database. After completing a SWASH session the user should manually perform simulations with the three individual models

Published
2015

25. Sediment properties in five Dutch watercourses : indicative measurements for the registration procedure of plant protection products in The Netherlands

Author

Adriaanse, P.I., Crum, S.J.H., Elbers, J.A., Massop, H.T.L., and Beltman, W.H.J.

Subjects
Environmental Risk Assessment, Integraal water-en stroomgeb.management, water bottoms, tuinbouw, ditches, horticulture, surface water, toxicologie, pesticides, sloten, arable farming, Climate Resilience, oppervlaktewater, Klimaatbestendigheid, pesticiden, akkerbouw, waterbodems, toxicology
Abstract

Van vijf sloten verspreid liggend over Nederland, zijn de sediment eigenschappen droge bulkdichtheid, organische-stofgehalte en porositeit zijn als functie van de diepte gemeten. Het betreft hier akkerbouw- en tuinbouwgebieden. De gevonden waarden verschillen duidelijk van de gebruikte waarden voor sediment in de oppervlaktewater scenario’s, die momenteel worden ontwikkeld voor de Nederlandse registratieprocedure voor gewasbeschermingsmiddelen (die zijn overgenomen van de EU-FOCUS scenario’s).

Published
2015

26. Leaching of plant protection products and their transformation products : proposals for improving the assessment of leaching to groundwater in the Netherlands : version 2

Author

Boesten, J.J.T.I., van der Linden, A.M.A., Beltman, W.H.J., and Pol, J.W.

Subjects
Environmental Risk Assessment, soil chemistry, adsorptie, estimation, chemische afbraak, pesticides, chemical degradation, leaching, models, bodemchemie, adsorption, pesticiden, uitspoelen, schatting, modellen
Abstract

Assessment of leaching of plant protection products to groundwater is an important aspect of the environmental risk assessment of these substances. Analysis of available Dutch groundwater monitoring data for these substances triggered a critical review of the current Dutch leaching assessment. As a result, proposals were developed for improving this assessment. These include: (i) a procedure for correcting systematic errors in measured sorption coefficients, (ii) a preliminary procedure for a quality check of Freundlich exponents, (iii) a flow chart for obtaining parameters describing the relationship between the organic-matter/water distribution coefficient, Kom, and the pH for weak acids, (iv) a procedure for obtaining a Kom endpoint from a population of Kom values including lower and upper limits, (v) a procedure for estimating the total amount of substance in soil from a concentration profile (needed for assessment of degradation half-lives from field experiments). This report is an update of the proposals reported in 2011 by the same authors based on testing the feasibility of the proposals to a few dossiers

Published
2015

27. Transformation by photolysis in water in the pesticide model TOXSWA : implementation report

Author

Beltman, W.H.J., Mulder, H.M., ter Horst, M.M.S., and Wipfler, E.L.

Subjects
Environmental Risk Assessment, water pollution, adsorptie, water bottoms, ecotoxicologie, pesticides, Bodem, Water en Landgebruik, ecotoxicology, models, fotolyse, Soil, Water and Land Use, biochemical pathways, photolysis, adsorption, pesticiden, biochemische omzettingen, waterverontreiniging, waterbodems, modellen
Abstract

The TOXSWA model has been extended with the functionality to simulate photolysis in water. TOXSWA simulates the fate of substances in water bodies to calculate exposure concentrations for aquatic organisms or sediment-dwelling organisms as part of the risk assessment of plant protection products (PPP). Photolysis is modelled as a first-order process, where transformation occurs in the water phase only. The transformation rate is considered to be linearly proportional to global radiation. Studies in outdoor surface water systems can in principle be used to derive the PPP transformation rates due to photolysis.

Published
2015

30. Calculation of exposure concentrations for NL standard scenarios by the TOXSWA model : use of FOCUS_TOXSWA 4.4.3 software for plant protection products and their metabolitesin Dutch risk assessment for aquatic ecosystems

Author

Beltman, W.H.J., Vink, C., Poot, A., Beltman, W.H.J., Vink, C., and Poot, A.

Abstract

TOXSWA calculates exposure concentrations of plant protection products in water and in sediment and isused in risk assessment studies of aquatic organisms. Replacement of the TOXSWA 1.2 software by the morerecent FOCUS_TOXSWA software for use with the NL standard scenarios was investigated. The impact of thereplacement on the calculated exposure concentrations of parent compounds and of metabolites wasdetermined. For parent substances the calculated exposure concentrations of the two TOXSWA versions wereequivalent. Due to a different way to simulate metabolites, the differences in exposure concentrationscalculated by the two versions can be large. For the simulation of metabolite substances two approaches aregiven to handle situations where the formation fraction is not known., TOXSWA berekent blootstellingsconcentraties van gewasbeschermingsmiddelen in water en in sediment voorde risicobeoordeling van aquatische organismen. Onderzocht is of de TOXSWA 1.2 software kan wordenvervangen door de meer recente FOCUS_TOXSWA software om te gebruiken met de NL standaardscenario’s.De invloed van vervanging van TOXSWA 1.2 door FOCUS_TOXSWA 4.4.3 op de berekende blootstellingsconcentratiesvan moederstoffen en van metabolieten is bepaald. De berekende blootstellingsconcentratiesvoor moederstoffen met de twee TOXSWA-modelversies kwamen overeen. Door het verschil in methodiekvan het simuleren van metabolieten kunnen er grote verschillen zijn in de berekende blootstellingsconcentratiesvoor metabolieten berekend door de twee modelversies. Om metabolieten te simuleren,worden twee methoden gegeven voor gevallen waarin de vormingsfractie van de metaboliet niet bekend is.

Published
2016

31. The TOXSWA model version 3.3 for pesticide behaviour in small surface waters : description of processes

Author

ter Horst, M.M.S., Beltman, W.H.J., van den Berg, F., ter Horst, M.M.S., Beltman, W.H.J., and van den Berg, F.

Abstract

In the European Union (EU) the risk of plant protection products to aquatic organisms is assessed accordingto regulation 1107/2009. For this assessment the FOCUS Surface Water Scenarios have been developed. TheTOXSWA model is included in the FOCUS Surface Water Software tools to calculate the exposureconcentration in the water systems defined in those scenarios. At the national level the TOXSWA model isused to assess the exposure concentration in the water system defined in national scenarios. In this report adescription is given of the hydrology in the Dutch and EU water body systems and the fate of pesticides andtheir metabolites in water and sediment. The pesticide can enter the system by spray drift and/or drainageand run-off. The transport in the water system is described by advection, dispersion and diffusion. Theexchange at the water-sediment interface is described based on advection/diffusion. Other processes aresorption, volatilisation at the water – air interface and transformation in both the water layer and thesediment. The formation and transformation of metabolites in both compartments are described. The reportpresents an outlook on the improvements in the next version as well as on future developments.

Published
2016

32. Metabolite formation in water and in sediment in the TOXSWA model : theory and procedure for the upstream catchment of FOCUS streams

Author

Adriaanse, P.I., Beltman, W.H.J., and van den Berg, F.

Subjects
Environmental Risk Assessment, water pollution, stroomgebieden, water bottoms, risk analysis, watersheds, pesticides, models, pesticiden, risicoanalyse, WOT Natuur & Milieu, waterverontreiniging, waterbodems, modellen
Abstract

Het TOXSWA model is uitgebreid met de beschrijving van vorming en omzetting van metabolieten in water en sediment. Op EU niveau wordt TOXSWA gebruikt in de aquatische risico beoordelingsmethodiek van bestrijdingsmiddelen om blootstellingsconcentraties te berekenen in de diverse water typen van de zogenaamde EU-FOCUS oppervlaktewater scenario’s. Voor de scenario’s met FOCUS riviertjes is er een bovenstrooms stroomgebied van 100 ha waarvan 20 ha met bestrijdingsmiddel is behandeld. Bij deze scenario’s willen we rekening houden met metabolieten die in het stroomgebied zijn gevormd. Daarom is een procedure ontwikkeld om de metaboliet concentraties en fluxen te corrigeren voor de FOCUS riviertjes, gevoed door het gedeeltelijk behandelde stroomgebied. De correctiefactoren van de procedure kunnen op twee manieren worden bepaald: (i) een simpele manier, waarbij de correctiefactor een functie is van de omzettingssnelheid van de moederstof en (ii) een meer gedetailleerde manier waarbij de correctiefactor een functie is van de omzettingssnelheid van zowel de moederstof als van de metaboliet, alsmede van de verblijftijd van de moederstof in het bovenstroomse stroomgebied.

Published
2014

33. Gedrag van chloorprofam en 3-chlooraniline in de bodem : bepaling van adsorptie, omzetting en uitloging met tarragrond van aardappelen

Author

Beltman, W.H.J., Matser, A.M., van der Linden, A.M.A., and Brand, E.

Subjects
Environmental Risk Assessment, groundwater pollution, germination inhibitors, adsorptie, aardappelen, CWC - Environmental Risk Assessment, grondwaterverontreiniging, opslag, aardappelopslagplaatsen, potato stores, storage, leaching, CWK - Environmental Risk Assessment, adsorption, uitspoelen, potatoes, kiemremmers
Abstract

Bij de bewaring van aardappelen wordt als kiemremmer de werkzame stof chloorprofam gebruikt. Na verwerking van de aardappelen in de fabriek blijft chloorprofam en haar omzettingsprodukt 3-chlooraniline in de resterende tarragrond aanwezig. De tarragrond wordt hergebruikt in grootschalige bodemtoepassingen. Omzetting, adsorptie en uitloging van chloorprofam en haar metaboliet 3-chlooraniline zijn onderzocht met tarragrond van aardappelen (onbelast en belast met chloorprofam) en met bouwvoorgrond. De omzettingssnelheid van chloorprofam en 3-chlooraniline is bepaald in bouwvoorgrond, in onverzadigde onbelaste tarragrond en in waterverzadigde onbelaste tarragrond. De adsorptieparameters van de Freundlich sorptie isotherm zijn bepaald voor 3-chlooraniline in onbelaste tarragrond en in bouwvoorgrond. De uitloogproeven zijn gedaan met onverzadigde belaste tarragrond en met waterverzadigde belaste tarragrond. De omzettingssnelheden en adsorptieparameters uit deze studie worden gebruikt voor het bepalen van het risico van uitspoeling van chloorprofam en 3-chlooraniline uit grote bodemtoepassingen naar het grondwater.

Published
2014

34. FOCUS_TOXSWA manual 4.4.2 : User’s Guide version 4

Author

Beltman, W.H.J., ter Horst, M.M.S., Adriaanse, P.I., de Jong, A., and Deneer, J.W.

Subjects
Environmental Risk Assessment, water pollution, plassen, water bottoms, Alterra - Centrum Geo-informatie, toxicologie, pesticides, Centre Geo-information, streams, models, waterlopen, pesticiden, WOT Natuur & Milieu, Alterra - Centre for Water and Climate, waterverontreiniging, ponds, waterbodems, modellen, Alterra - Centrum Water en Klimaat, toxicology
Abstract

The FOCUS_TOXSWA model calculates exposure concentrations of pesticides and their metabolites in watercourses and ponds. These concentrations are used in the pesticide registration procedure at EU level. The model concepts of TOXSWA are described briefly. The input files, output files, and the use of the graphical user interface to access the input and output are described. Input data are stored in a database. Pesticide entries resulting from drainage or runoff/erosion are accessed from separate files generated by FOCUS_MACRO and FOCUS_PRZM. Substance properties are accessed from the SPIN tool/database. Instructions for simulating a water-sediment study and a multi-year run are given

Published
2014

35. SPIN manual 1.1 : user’s guide version 1, for use with FOCUS_SWASH 4.2

Author

van Kraalingen, D.W.G., Wipfler, E.L., van den Berg, F., Beltman, W.H.J., ter Horst, M.M.S., Fait, G., and te Roller, J.A.

Subjects
Environmental Risk Assessment, Earth Observation and Environmental Informatics, handboeken, databases, CWC - Environmental Risk Assessment, pesticides, handbooks, CWK - Environmental Risk Assessment, registration, pesticiden, WOT Natuur & Milieu, Aardobservatie en omgevingsinformatica, computer software, databanken, registratie
Abstract

This manual addresses the main functionalities of the Substance Plug IN tool, SPIN version 1.1, which is released together with FOCUS_SWASH 4.2 and FOCUS_TOXSWA 4.4.2. SPIN is basically a database that stores all substance properties relevant to the listed pesticide fate software. New substances can be added to the database by copying an existing substance or by creating a new substance. The database can also be copied and exchanged between (advanced) users, whereas substances can also be exported and imported. SPIN can be run in two different modes, either standalone, in which case all properties are accessible and can all be filled in, or when started from a host application, in which case only the host-required properties are accessible. SPIN has been developed such that all new releases of SPIN can communicate with earlier released host-applications

Published
2013

36. SWASH Manual 4.2 : user’s guide version 4

Author

Fait, G., van den Berg, F., Adriaanse, P.I., de Jong, A., te Roller, J.A., and Beltman, W.H.J.

Subjects
Environmental Risk Assessment, Earth Observation and Environmental Informatics, water pollution, soil pollution, bodemverontreiniging, soil water, surface water, pesticides, bodemwater, models, oppervlaktewater, pesticiden, WOT Natuur & Milieu, Aardobservatie en omgevingsinformatica, waterverontreiniging, modellen
Abstract

SWASH (Surface WAter Scenarios Help) assists the user in calculating pesticide exposure concentration in the EU FOCUS surface water scenarios. It is part of the exposure calculation procedure, being part of the obligatory evaluation procedure to place an active substance on List 1 according to EU Directive 91/414/EEC. SWASH encompasses: (i) FOCUS Drift Calculator, calculating pesticide entries through spray drift deposition, (ii) PRZM-3, calculating pesticide entries through run-off, (iii) MACRO, calculating pesticide entries through drainage and (iv) TOXSWA, calculating the behaviour of pesticides in small surface waters. It is linked to SPIN, a pesticide properties tool, and prepares input for the PRZM, MACRO and TOXSWA models. Via the SWASH shell the user can enter the shells of the other models to perform the PRZM or MACRO model runs needed to assess the fate of the substance in he FOCUS water body systems using TOXSWA.

Published
2013

37. Emissie door oppervlakkige afspoeling : relevantie en preventie : tussenrapportage 2011

Author

Evenhuis, A., Beltman, W.H.J., van der Weide, R.Y., van Zeeland, M.G., Schepers, H.T.A.M., and Deneer, J.W.

Subjects
plant protection, gewasbescherming, CWC - Environmental Risk Assessment, pesticide residues, surface water, runoff, pesticides, precipitation, pesticidenresiduen, infiltration, landbouwgronden, oppervlakkige afvoer, OT Acrres, meteorological observations, emissie, infiltratie, neerslag, oppervlaktewater, CWK - Environmental Risk Assessment, pesticiden, emission, Wageningen Environmental Research, agricultural soils, meteorologische waarnemingen, OT Team Schimmels Onkr. en Plagen
Abstract

De doelstelling van het rapportage-project was: - Op basis van bestaande kennis uit binnen- en buitenland (metingen, modelstudies) inzichtelijk maken in hoeverre oppervlakkige afspoeling van (vrijwel) vlakke percelen verantwoordelijk kan zijn voor (piek) belasting van oppervlaktewater; - Inzichtelijk maken in hoeverre een vergelijking met andere emissieroutes mogelijk is en, zo mogelijk, deze vergelijking inzichtelijk maken; - Verkenning van de mate van overeenstemming tussen de uitgangspunten van de modelmatige berekening van afspoeling en de situatie op representatieve praktijksituaties in Nederland. Wanneer relevante afwijkingen verwacht worden, deze benoemen; - Vaststellen of er zicht is op effectieve maatregelen om oppervlakkige afspoeling tegen te gaan. Dit kunnen bestaande of nieuwe maatregelen zijn. Hiervoor is een korte internationale literatuurscan uitgevoerd naast een verkenning om te bepalen hoe vaak afspoeling van water kan optreden op landbouwgronden in het vlakke deel van Nederland. Voor dit laatste onderdeel zijn neerslaggegevens van 30 jaar geanalyseerd op de frequentie van optreden van buien voor 3 meteostations en zijn zand- en kleigronden gekarakteriseerd met hun infiltratiesnelheid.

Published
2012

38. Biologische zuivering van water verontreinigd met gewasbeschermingsmiddelen : onderzoeksresultaten 2008 t/m 2011

Author

de Werd, H.A.E., Wenneker, M., Looij, J.H., Beltman, W.H.J., van der Lans, A.M., Huiting, H.F., de Bruine, J.A., and van Zeeland, M.G.

Subjects
plant protection, afvalwaterbehandeling, gewasbescherming, CWC - Environmental Risk Assessment, PPO BBF Bloembollen, PPO BBF Fruitgewassen, pesticides, water treatment, dosering, waterzuivering, dosage, emissie, waste water treatment, CWK - Environmental Risk Assessment, Fruit, pesticiden, emission, biologische behandeling, Flower Bulbs, Wageningen Environmental Research, biological treatment, OT Team Schimmels Onkr. en Plagen
Abstract

In dit rapport worden de resultaten beschreven van het onderzoek van WUR PPO, in samenwerking met WUR Alterra, naar de inzetbaarheid van biologische zuiveringstechnieken voor verwerking van afvalwater, dat verontreinigd is met gewasbeschermingsmiddelen. De onderzochte toepassingen zijn gericht op land- en tuinbouwbedrijven, inclusief loonbedrijven en exclusief glastuinbouwbedrijven. Voor de glastuinbouw worden de mogelijkheden van zuivering ook onderzocht, maar ligt de focus meer op andere technieken dan biologische zuivering. In de glastuinbouw gaat het met name om drain- en drainagewater. Omdat de basisprincipes van de werking van systemen voor biologische zuivering al onderzocht zijn door onder andere Vlaamse universiteiten en onderzoeksinstellingen, is er in Nederland vooral onderzoek gedaan naar het gebruik en de effectiviteit van deze installaties onder praktische omstandigheden.

Published
2012

39. Puntemissies van gewasbeschermingsmiddelen naar oppervlaktewater : vergelijking van activiteiten op het erf met het POSSUM-model

Author

Beltman, W.H.J., Wenneker, M., van Zeeland, M.G., van der Lans, A.M., van der Weide, R.Y., and de Werd, H.A.E.

Subjects
spraying equipment, spuitapparatuur, CWC - Environmental Risk Assessment, PPO BBF Bloembollen, PPO BBF Fruitgewassen, pesticides, oppervlaktewaterkwaliteit, farms, landbouwbedrijven, clearing, CWK - Environmental Risk Assessment, Fruit, yards, pesticiden, Flower Bulbs, Wageningen Environmental Research, erven, reiniging, OT Team Schimmels Onkr. en Plagen, surface water quality
Abstract

Puntbronnen kunnen bijdragen aan emissies naar oppervlaktewater. Activiteiten op het erf die tot puntemissies kunnen leiden zijn vergeleken en gerangschikt. POSSUM (POint Sources SUrface waters Model) vergelijkt de risico’s van verschillende activiteiten op basis van gegevens over activiteiten en bedrijfssituaties; op basis van kennis omtrent depositie van reststromen met gewasbeschermingsmiddelen (in putten, op het erf of op de bodem), en de frequentie waarin verschillende activiteiten ten opzichte van elkaar worden uitgevoerd. De activiteiten worden vergeleken op bedrijfsniveau op de schaal van een bedrijf voor een periode van één jaar. De emissies in dit rapport zijn berekend op basis van gegevens die van 2006 tot 2008 verzameld zijn. Voor de akkerbouw is voor de werkzame stof terbutylazin de grootste emissie berekend voor het vullen van de spuittank. Voor de bloembollenteelt is voor de werkzame stoffen pirimifos-methyl en prochloraz de grootste emissie berekend bij het spoelen van geoogste bollen en het reinigen van kuubskisten. Voor de fruitteelt is voor de werkzame stof imidacloprid de berekende emissie het grootst bij het uitwendig reinigen van de spuitapparatuur.

Published
2011

40. Non-stationary flow solution for water levels in open channels for TOXSWA

Author

van Opheusden, J.H.J., Molenaar, J., Beltman, W.H.J., and Adriaanse, P.I.

Subjects
water pollution, CWC - Environmental Risk Assessment, ditches, surface water, pesticides, sloten, Wiskundige en Statistische Methoden - Biometris, models, oppervlaktewater, CWK - Environmental Risk Assessment, pesticiden, waterverontreiniging, Wageningen Environmental Research, Mathematical and Statistical Methods - Biometris, modellen
Abstract

We study non-stationary flow in open discharge channels. A model is derived from basic principles, conservation of mass and momentum, which is solved numerically for the cross sectional area and discharge as a function of time and position along the channel. The model describes the effect of external inflow from fields adjacent to the channel. Several scenarios are calculated, both for very slowly, and more rapidly flowing water courses.

Published
2011

41. Biozuiveringssystemen voor de open teelten : stand van zaken van onderzoek 2009

Author

Wenneker, M., Beltman, W.H.J., van der Lans, A., van der Weide, R.Y., and de Werd, H.A.E.

Subjects
afvalwaterbehandeling, CWC - Environmental Risk Assessment, bioremediëring, PPO BBF Fruitgewassen, waterfilters, vollegrondsteelt, netherlands, water filters, pesticides, farms, outdoor cropping, nederland, landbouwbedrijven, CWK - Environmental Risk Assessment, waste water treatment, bioremediation, Fruit, pesticiden, Wageningen Environmental Research, OT Team Schimmels Onkr. en Plagen
Abstract

In dit project werd gezocht naar zuiveringssystemen voor de verwerking van restwater die gemakkelijk op bedrijven zijn te implementeren. Daarbij is voor agrariërs belangrijk dat de systemen goedkoop en betrouwbaar zijn, met een minimum aan arbeid, maar hoog rendement.

Published
2010

42. Biozuiveringssytemen voor de open teelten

Author

Wenneker, M., Beltman, W.H.J., van der Lans, A.M., van der Weide, R.Y., and van Zeeland, M.G.

Subjects
CWK - Environmental Risk Assessment, Fruit, CWC - Environmental Risk Assessment, PPO BBF Bloembollen, PPO BBF Fruitgewassen, Flower Bulbs, Life Science, Wageningen Environmental Research, OT Team Schimmels Onkr. en Plagen
Published
2010

44. Stationary flow solution for water levels in open channels

Author

van Opheusden, J.H.J., Molenaar, J., Beltman, W.H.J., and Adriaanse, P.I.

Subjects
CWC - Environmental Risk Assessment, constante stroming, water flow, afvoer, water level, channels, Wiskundige en Statistische Methoden - Biometris, models, CWK - Environmental Risk Assessment, discharge, waterstand, kanalen, klein, steady flow, Mathematical and Statistical Methods - Biometris, waterstroming, modellen, Computer Science::Information Theory
Abstract

We study stationary flow in open discharge channels. A model is derived from basic principles, which is solved numerically for the water level and discharge as a function of position along the channel. The model describes the effect of external inflow from fields adjacent to the channel. Several scenarios are calculated, both for very slowly, and more rapidly flowing water courses.

Published
2010

45. Quantifying point source entries of pesticides in surface waters. International Advances in Pesticide Application

Author

Wenneker, M., Beltman, W.H.J., de Werd, H.A.E., van Zeeland, M.G., van der Lans, A.M., and van der Weide, R.Y.

Subjects
Praktijkonderzoek Plant & Omgeving, Sector Fruit, Nursery Stock-Flower Bulbs, CWK - Environmental Risk Assessment, Applied Plant Research, Fruit Research Unit, PPO Bloembollen en Bomen, CWC - Environmental Risk Assessment, Alterra - Centre for Water and Climate, Life Science, Wageningen Environmental Research, PPO Arable Farming, Multifunctional Agriculture and Field Production of Vegetables, PPO Akkerbouw, Groene Ruimte en Vollegrondsgroente, Alterra - Centrum Water en Klimaat
Abstract

Measurements of the water boards have shown that pesticide concentrations in surface water have decreased less than was expected based on model calculations. Possibly, the implementation of spray drift reducing techniques is overestimated in the model calculation. The impact of point sources is probably underestimated. A project was initiated for the quantification and qualification of possible point sources in Dutch agriculture. Several point source entries were identified: e.g. internal and external cleaning of sprayers, filling stations and discharge of transport water from fruit sorting installations. A method was developed to discriminate the contamination of the pesticide activities in their possible impact on surface waters; the POint Source SUrface waters Model (POSSUM).

Published
2010

46. Transformation reactions in TOXSWA : transformation reactions of plant protection products in surface water

Author

Deneer, J.W., Beltman, W.H.J., and Adriaanse, P.I.

Subjects
CWC - Environmental Risk Assessment, surface water, pesticides, fotolyse, oppervlaktewater, hydrolysis, photolysis, CWK - Environmental Risk Assessment, hydrolyse, pesticiden, Wageningen Environmental Research, biotransformation, biotransformatie
Abstract

This report aims to give a general description of transformation processes for future use in the TOXSWA model. Hydrolysis, photolysis and biotic transformation are described as distinct processes, employing separate rate constants. Additionally, a way to introduce into TOXSWA the daily variation of pH and temperature is proposed.

Published
2010

47. Transient water flow in the TOXSWA model (FOCUS) versions): concepts and mathematical description

Author

Adriaanse, P.I. and Beltman, W.H.J.

Subjects
ditches, meren, simulation models, sloten, oppervlaktewaterkwaliteit, water quality, milieubescherming, waterlopen, discharge, pesticiden, lakes, Alterra - Centre for Water and Climate, Wageningen Environmental Research, environmental protection, european union, afvoer, authorisation of pesticides, toxicologie, pesticides, waterkwaliteit, streams, simulatiemodellen, europese unie, toelating van bestrijdingsmiddelen, WOT Natuur & Milieu, drainage, surface water quality, toxicology, Alterra - Centrum Water en Klimaat
Abstract

The TOXSWA model is used in the pesticide registration procedures in the Netherlands and the EU. This report documents the transient water flow module of TOXSWA, which simulates variable discharges and water depths in the edge-of-field ponds, ditches and streams of the EU FOCUS Surface Water Scenarios at an hourly resolution. It combines water conservation equations with water depth-discharge relations based upon weirs located downstream. In watercourses, backwater curves describe water depths as a function of distance to the weir. The water conservation equations consist of a base flow, excess water fluxes from drainage or runoff and an outflow. The conservation equations have been solved numerically using the finite difference method. A limited verification of the numerical solution has been undertaken. Example runs present model input and output Het model TOXSWA wordt gebruikt in de toelatingsprocedures van bestrijdingsmiddelen in Nederland en in de EU. Dit rapport documenteert het onderdeel van TOXSWA met een niet-eenparige (dus in de stromingsrichting veranderende) waterstroming. Dit onderdeel simuleert op uurbasis veranderende afvoeren en waterdiepten in de FOCUS Oppervlaktewater Scenario’s van de EU: meertjes, sloten en beekjes grenzend aan landbouwpercelen. Waterconserveringsvergelijkingen worden gecombineerd met afvoerformules voor benedenstrooms gelegen stuwen, die het verband tussen de afvoer en de overstorthoogte geven. In de waterlopen beschrijven stuwkrommen het verloop van de waterdiepte met de afstand tot de stuw. De waterconserverings-vergelijkingen bevatten een basisafvoer, overtollige waterfluxen door drainagebuizen of via oppervlakte-afvoer en een uitstroming. De conserveringsvergelijkingen zijn numeriek opgelost met de eindige differentiemethode. De numerieke oplossing is beperkt geverifieerd. Voorbeeldsimulaties tonen de modelinvoer en -uitvoer. We bevelen aan om de wiskundige beschrijving van de waterstroming te verbeteren door een geleidelijk veranderende en discontinue waterstromingsbeschrijving te implementeren, dus met langs de waterloop in- of uitstromend water.Trefwoorden: FOCUS oppervlaktewater scenario’s, bestrijdingsmiddelen toelating, TOXSWA, niet-eenparige waterstroming.

Published
2009

48. PRIMET version 2.0, technical description and manual : a decision support system for assessing Pesticide RIsks in the tropics to Man, Environment and Trade

Author

Peeters, F.M., van den Brink, P.J., Vlaming, J., Groenwold, J.G., Beltman, W.H.J., and Boesten, J.J.T.I.

Subjects
vegetables, Aquatic Ecology and Water Quality Management, Alterra - Centrum Geo-informatie, groenten, blootstelling, environmental impact, tropics, beslissingsondersteunende systemen, ontwikkelingslanden, pesticiden, tropen, Alterra - Centre for Water and Climate, Wageningen Environmental Research, milieueffect, risk assessment, health, developing countries, pesticides, Centre Geo-information, Aquatische Ecologie en Waterkwaliteitsbeheer, risicoschatting, exposure, gezondheid, decision support systems, Alterra - Centrum Water en Klimaat
Abstract

Pesticide exposure via for instance spray drift or runoff to surface water, accumulation in the topsoil, and leaching to groundwater potentially affects organisms in water, in and around soil and on plants and might also pose risks to humans via dietary exposure, in case they consume contaminated products like groundwater, macrophytes and fish. To estimate these risks at the household level the PRIMET Decision Support System was developed. PRIMET runs with a minimum of input data and is developed to be used in developing countries

Published
2008

49. Nalevering van carbendazim uit slootbodems in bollenteeltgebieden : de rol van nalevering uit slootbodems bij het ontstaan van normoverschrijdingen in oppervlaktewater

Author

van der Lans, A.M. and Beltman, W.H.J.

Subjects
water pollution, soil pollution, water bottoms, bodemverontreiniging, PPO Bloembollen en Bomen, ornamental bulbs, bloembollen, pesticides, emissie, Nursery Stock-Flower Bulbs, pesticiden, emission, Alterra - Centre for Water and Climate, waterverontreiniging, waterbodems, Alterra - Centrum Water en Klimaat
Abstract

In discussie tussen de waterschappen, onderzoekers en bollentelers werd geopperd dat de overschrijdingen van carbendazim in het oppervlaktewater mogelijk niet alleen worden veroorzaakt door recente emissieroutes op het erf en het veld, maar dat nalevering van carbendazim uit sediment dat door vroegere emissies verontreinigd is geraakt ook een rol kan spelen. Die invloed vanuit het sediment kan er wel zijn maar zal maar een beperkte rol spelen bij verontreinigingen

Published
2008

50. Spatial moment analysis of transport of nonlinearly absorbing pesticides using analytical approximations

Author

Beltman, W.H.J., Boesten, J.J.T.I., and van der Zee, S.E.A.T.M.

Subjects
WIMEK, model, sorption, Leerstoelgroep Bodemnatuurkunde, ecohydrologie en grondwaterbeheer, soil, nonequilibrium solute transport, groundwater, Alterra - Centre for Water and Climate, Soil Physics, Ecohydrology and Groundwater Management, Wageningen Environmental Research, contaminant transport, porous-media, Alterra - Centrum Water en Klimaat, degradation
Abstract

Analytical approximations were derived for solute transport of pesticides subject to Freundlich sorption, and first-order degradation restricted to the liquid phase. Solute transport was based on the convection-dispersion equation (CDE) assuming steady flow. The center of mass (first spatial moment) was approximated both for a non-degraded solute pulse and for a pulse degraded in the liquid phase. The remaining mass (zeroth spatial moment) of a linearly sorbing solute degraded in the liquid phase was found to be a function of only the center of mass (first spatial moment) and the Damköhler number (i.e., the product of degradation rate coefficient and dispersivity divided by flow velocity). This relationship between the zeroth and first spatial moments was shown to apply to nonlinearly sorbing pulses as well. The mass fraction leached of a pesticide subject to Freundlich sorption and first-order degradation in the solution phase only was found to be a function of the Damköhler number and of the dispersivity, so independent of sorption. Hence perceptions of the effects of sorption on pesticide leaching should be reconsidered. These conclusions equally hold for other micropollutants that degrade in the solution phase only

Published
2008

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