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Ecological risk assessment (ERA) has followed a taxonomy-based approach, making the assumption that related species will show similar sensitivity to toxicants, and using safety factors or species sensitivity distributions to extrapolate from tested to untested species. In ecology it has become apparent that taxonomic approaches may have limitations for the description and understanding of species assemblages in nature. Therefore it has been proposed that the inclusion of species traits in ERA could provide a useful and alternative description of the systems under investigation. At the same time, there is a growing recognition that the use of mechanistic approaches in ERA, including conceptual and quantitative models, may improve predictive and extrapolative power. Purposefully linking traits with mechanistic effect models could add value to taxonomy-based ERA by improving our understanding of how structural and functional system facets may facilitate inter-species extrapolation. Here, we explore whether and in what ways traits can be linked purposefully to mechanistic effect models to predict intrinsic sensitivity using available data on the acute sensitivity and toxicokinetics of a range of freshwater arthropods exposed to chlorpyrifos. The results of a quantitative linking of seven different endpoints and twelve traits demonstrate that while quantitative links between traits and/or trait combinations and process based (toxicokinetic) model parameters can be established, the use of simple traits to predict classical sensitivity endpoints yields little insight. Remarkably, neither of the standard sensitivity values, i.e. the LC50 or EC50, showed a strong correlation with traits. Future research in this area should include a quantitative linking of toxicodynamic parameter estimations and physiological traits, and requires further consideration of how mechanistic trait-process/parameter links can be used for prediction of intrinsic sensitivity across species for different substances in ERA. Electronic supplementary material The online version of this article (doi:10.1007/s10646-012-0962-8) contains supplementary material, which is available to authorized users.

The ecological impact of the dithiocarbamate fungicide metiram was studied in outdoor freshwater microcosms, consisting of 14 enclosures placed in an experimental ditch. The microcosms were treated three times (interval 7 days) with the formulated product BAS 222 28F (Polyram®). Intended metiram concentrations in the overlying water were 0, 4, 12, 36, 108 and 324 μg a.i./L. Responses of zooplankton, macroinvertebrates, phytoplankton, macrophytes, microbes and community metabolism endpoints were investigated. Dissipation half-life (DT50) of metiram was approximately 1–6 h in the water column of the microcosm test system and the metabolites formed were not persistent. Multivariate analysis indicated treatment-related effects on the zooplankton (NOECcommunity = 36 μg a.i./L). Consistent treatment-related effects on the phytoplankton and macroinvertebrate communities and on the sediment microbial community could not be demonstrated or were minor. There was no evidence that metiram affected the biomass, abundance or functioning of aquatic hyphomycetes on decomposing alder leaves. The most sensitive populations in the microcosms comprised representatives of Rotifera with a NOEC of 12 μg a.i./L on isolated sampling days and a NOEC of 36 μg a.i./L on consecutive samplings. At the highest treatment-level populations of Copepoda (zooplankton) and the blue-green alga Anabaena (phytoplankton) also showed a short-term decline on consecutive sampling days (NOEC = 108 μg a.i./L). Indirect effects in the form of short-term increases in the abundance of a few macroinvertebrate and several phytoplankton taxa were also observed. The overall community and population level no-observed-effect concentration (NOECmicrocosm) was 12–36 μg a.i./L. At higher treatment levels, including the test systems that received the highest dose, ecological recovery of affected measurement endpoints was fast (effect period

In agroecosystems, organisms may regularly be exposed to anthropogenic stressors, e.g. pesticides. Species' sensitivity to stress depends on toxicity, life-history, and landscape structure. We developed an individual-based model of an isopod, Asellus aquaticus, to explore how timing of stress events affects population dynamics in a seasonal environment. Furthermore, we tested the relevance of habitat connectivity and spatial distribution of stress for the recovery of a local and total population. The simulation results indicated that population recovery is mainly driven by reproductive periods. Furthermore, high habitat connectivity led to faster recovery both for local and total populations. However, effects of landscape structure disappeared for homogeneously stressed populations, where local survivors increased recovery rate. Finally, local populations recovered faster, implying that assessing recovery in the field needs careful consideration of spatial scale for sampling. We emphasize the need for a coherent definition of recovery for more relevant ecosystem risk assessment and management.

This paper evaluates the effects of different time-varying exposure patterns of the strobilurin fungicide azoxystrobin on freshwater microsocosm communities. These exposure patterns included two treatments with a similar peak but different time-weighted average (TWA) concentrations, and two treatments with similar TWA but different peak concentrations. The experiment was carried out in outdoor microcosms under four different exposure regimes; (1) a continuous application treatment of 10 μg/L (CAT(10)) for 42 days (2), a continuous application treatment of 33 μg/L (CAT(33)) for 42 days (3), a single application treatment of 33 μg/L (SAT(33)) and (4) a four application treatment of 16 μg/L (FAT(16)), with a time interval of 10 days. Mean measured 42-d TWA concentrations in the different treatments were 9.4 μg/L (CAT(10)), 32.8 μg/L (CAT(33)), 14.9 μg/L (SAT(33)) and 14.7 μg/L (FAT(16)). Multivariate analyses demonstrated significant changes in zooplankton community structure in all but the CAT(10) treated microcosms relative to that of controls. The largest adverse effects were reported for zooplankton taxa belonging to Copepoda and Cladocera. By the end of the experimental period (day 42 after treatment), community effects were of similar magnitude for the pulsed treatment regimes, although the magnitude of the initial effect was larger in the SAT(33) treatment. This indicates that for long-term effects the TWA is more important for most zooplankton species in the test system than the peak concentration. Azoxystrobin only slightly affected some species of the macroinvertebrate, phytoplankton and macrophyte assemblages. The overall no observed ecologically adverse effect concentrations (NOEAEC) in this study was 10 µg/L.

Agricultural practices are essential for sustaining the human population, but at the same time they can directly disrupt ecosystem functioning. Ecological risk assessment (ERA) aims to estimate possible adverse effects of human activities on ecosystems and their parts. Current ERA practices, however, incorporate very little ecology and base the risk estimates on the results of standard tests with several standard species. The main obstacles for a more ecologically relevant ERA are the lack of clear protection goals and the inherent complexity of ecosystems that is hard to approach empirically. In this paper, we argue that the ecosystem services framework offers an opportunity to define clear and ecologically relevant protection goals. At the same time, ecological models provide the tools to address ecological complexity to the degree needed to link measurement endpoints and ecosystem services, and to quantify service provision and possible adverse effects from human activities. We focus on the ecosystem services relevant for agroecosystem functioning, including pollination, biocontrol and eutrophication effects and present modeling studies relevant for quantification of each of the services. The challenges of the ecosystem services approach are discussed as well as the limitations of ecological models in the context of ERA. A broad, multi-stakeholder dialog is necessary to aid the definition of protection goals in terms of services delivered by ecosystems and their parts. The need to capture spatio-temporal dynamics and possible interactions among service providers pose challenges for ecological models as a basis for decision making. However, we argue that both fields are advancing quickly and can prove very valuable in achieving more ecologically relevant ERA.

Eén van de doelstellingen van het toelatingsbeleid van gewasbeschermingsmiddelen is te voorkomen dat, na goede landbouwkundige toepassing, deze middelen en hun omzettingsproducten een schadelijke uitwerking hebben op waterorganismen. Het kan verbazing wekken dat in watergangen de waterkwaliteitsnormen voor gewasbeschermingsmiddelen nog regelmatig overschreden worden, daar een strikt omschreven toelatingsbeleid is geïmplementeerd en diverse technische maatregelen zijn genomen om emissie van gewasbeschermingsmiddelen naar oppervlaktewater te voorkomen (o.a. drift reducerende sproeidoppen; bufferzones). Er wordt door sommigen geopperd dat het toelatingsbeleid niet geheel voldoet. Reden genoeg om nader in te gaan op recente ontwikkelingen bij de aquatische risicobeoordeling van gewasbeschermingsmiddelen in het kader van de toelating.

Little research has been done so far into the environmental fate and side effects of pesticides in the tropics. In addition, those studies conducted in tropical regions have focused almost exclusively on single species laboratory tests. Hence, fate and effects of pesticides on higher-tier levels have barely been studied under tropical conditions. To address this lack of knowledge, four outdoor aquatic model ecosystem experiments using two different test systems were conducted in Thailand evaluating the insecticide chlorpyrifos, the herbicide linuron and the fungicide carbendazim. Results of these experiments and comparisons of recorded fate and effects with temperate studies have been published previously. The present paper discusses the pros and cons of the methodologies applied and provides indications for i) possible improvements; ii) important aspects that should be considered when performing model ecosystem experiments in the tropics; iii) future research.

Environmental variables (including natural and anthropogenic stressors) and meiobenthic communities were sampled in a ‘natural’ (Rooiels) and a ‘disturbed’ (Lourens) estuary in the Western Cape, South Africa, bimonthly for 20 months. A primary aim of the study was to assess if the meiobenthic community structure is driven by different variables when comparing ‘natural’ versus ‘disturbed’ system. Due to the much smaller catchment of the Rooiels Estuary, many environmental variables were significantly different (p

Het is inmiddels een bekend feit dat ontwormingsmiddelen die aan vee worden gegeven, giftig kunnen zijn voor de mestfauna, de insecten die zich met mest voeden en er hun eieren in leggen. Het verdwijnen van bepaalde soorten mestfauna kan er in bepaalde gevallen toe leiden dat de afbraak van mest in het veld vertraagd wordt, zo blijkt uit buitenlandse studies. Enquêtes wezen eerder uit dat ontwormingsmiddelen in veel Nederlandse natuurgebieden worden toegediend aan grote grazers. Komen dit soort ecologische effecten dus ook in onze natuurgebieden voor? Dit is de afgelopen jaren door Alterra onderzocht in opdracht van het ministerie van EL&I.

In Nederland wordt aan de insectenorde Psocoptera (stofluis) weinig aandacht besteed. Er zijn dan ook nog meer soorten voor Nederland te verwachten dan nu bekend zijn. Hier wordt de soort Philotarsus parviceps voor het eerst voor Nederland gemeld. De vondt is weinig verrassend omdat de soort uit alle ons omringende landen (met uitzondering van Denemarken) bekend is. In dit artikel beschrijven wij deze nieuwe stofluis, inclusief de verschillen met de verwante soort P. picicornis die in dit artikel ook bevestigd wordt voor de Nederlandse fauna.

Van de verspreiding van boor- en prachtvliegen in Nederland is nog maar weinig bekend. In dit artikel worden waarnemingen van 17 soorten boorvliegen en drie soorten prachtvliegen behandeld. Het gaat hierbij of om zeldzame het gaat hierbij of om zeldzame soorten of om waarnemingen die een aanzienlijke uitbreiding van het areaal betreffen. Daarnaast wordt een nieuw overzicht gegeven van alle soorten prachtvliegen in Nederland met een verwijzing naar determinatieliteratuur.

The risk assessment of pesticides for freshwater ecosystems in the Amazon has relied on the use of toxicity data and water quality criteria derived for temperate regions due to a lack of ecotoxicological studies performed with indigenous species. This leaves an unknown margin of uncertainty for the protection of Amazonian ecosystems, as differences in environmental conditions and species sensitivity are not taken into account. To address this issue, the acute toxic effects of malathion (an organophosphorus insecticide) and carbendazim (a benzimidazole fungicide) were assessed on five fish and five freshwater invertebrates endemic to the Amazonian region. Subsequently, the intrinsic sensitivity of Amazonian and temperate freshwater species was compared using the species sensitivity distribution (SSD) concept. Amazonian species sensitivity to malathion was found to be similar to that of their temperate counterparts, with LC50 values ranging between 111 and 1507 g/l for fish species and 2.1426 g/l for arthropod species. However, Amazonian fish appeared to be slightly less sensitive for carbendazim than temperate fish with LC50 values ranging between 1648 and 4238 g/l, and Amazonian invertebrates were found to be significantly more resistant than their temperate counterparts, with LC50 values higher than 16000 g/l. The results of this study suggest that for these compounds, the use of water quality criteria derived with laboratory toxicity data for temperate species will result in a sufficient protection level for Amazonian freshwater organisms. Recommendations for further research include the validation of threshold concentrations derived with temperate standard test species and with the SSD model with semi-field experiments considering larger assemblages of indigenous species under local environmental conditions.

The effects of the parasiticide ivermectin were assessed in plankton-dominated indoor microcosms. Ivermectin was applied once at concentrations of 30, 100, 300, 1000, 3000, and 10,000 ng/l. The half-life (dissipation time 50%; DT₅₀) of ivermectin in the water phase ranged from 1.1 to 8.3 days. The lowest NOEC(community) that could be derived on an isolated sampling from the microcosm study by means of multivariate techniques was 100 ng/l. The most sensitive species in the microcosm study were the cladocerans Ceriodaphnia sp. (no observed effect concentration, NOEC = 30 ng/l) and Chydorus sphaericus (NOEC = 100 ng/l). The amphipod Gammarus pulex was less sensitive to ivermectin, showing consistent statistically significant reductions at the 1000-ng/l treatment level. Copepoda taxa decreased directly after application of ivermectin in the highest treatment but had already recovered at day 20 posttreatment. Indirect effects (e.g., increase of rotifers, increased primary production) were observed at the highest treatment level starting only on day 13 of the exposure phase. Cladocera showed the highest sensitivity to ivermectin in both standard laboratory toxicity tests as well as in the microcosm study. This study demonstrates that simple plankton-dominated test systems for assessing the effects of ivermectin can produce results similar to those obtained with large complex outdoor systems.

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).

Effects of soil properties on the accumulation of metals to wood mice (Apodemus sylvaticus) were evaluated at two sites with different pH and organic matter content of the soil. pH and organic matter content significantly affected accumulation of Cd, Cu, Pb and Zn in earthworms and vegetation. For Cd, Cu and Zn these effects propagated through the food web to the wood mouse. Soil-to-kidney ratios differed between sites: Cd: 0.15 versus 3.52, Cu: 0.37 versus 1.30 and Zn: 0.33–0.83. This was confirmed in model calculations for Cd and Zn. Results indicate that total soil concentrations may be unsuitable indicators for risks that metals pose to wildlife. Furthermore, environmental managers may, unintentionally, change soil properties while taking specific environmental measures. In this way they may affect risks of metals to wildlife, even without changes in total soil concentrations. Soil properties significantly affect accumulation of heavy metals to wood mice so; risks cannot be based on total concentrations.

In the evaluation of the risk of pesticide leaching to groundwater, the soil surface is usually assumed to be level, although important crops like potato are grown on ridges. A fraction of the water from rainfall and sprinkler irrigation may flow along the soil surface from the ridges to the furrows, thus bringing about an extra load of water and pesticide on the furrow soil. A survey of the literature reveals that surface-runoff from ridges to furrows is a well-known phenomenon but that hardly any data are available on the quantities of water and pesticide involved. On the basis of a field experiment with additional sprinkler irrigation, computer simulations were carried out with the Pesticide Emission Assessment at Regional and Local scales model for separate ridge and furrow systems in a humic sandy potato field. Breakthrough curves of bromide ion (as a tracer for water flow) and carbofuran (as example pesticide) were calculated for 1-m depth in the field. Bromide ion leached comparatively fast from the furrow system, while leaching from the ridge system was slower showing a maximum concentration of about half of that for the furrow system. Carbofuran breakthrough from the furrow system began about a month after application and increased steadily to substantial concentrations. Because the transport time of carbofuran in the ridge soil was much longer, no breakthrough occurred in the growing season. The maximum concentration of carbofuran leaching from the ridge-furrow field was computed to be a factor of six times as high as that computed for the corresponding level field. The study shows that the risk of leaching of pesticides via the furrow soil can be substantially higher than that via the corresponding level field soil.

Parathion-methyl is an organophosphorous insecticide that is widely used in agricultural production sites in the Amazon. The use of this pesticide might pose a potential risk for the biodiversity and abundance of fish and invertebrate species inhabiting aquatic ecosystems adjacent to the agricultural fields. Due to a lack of toxicity data for Amazonian species, safe environmental concentrations used to predict the ecological risks of parathion-methyl in the Amazon are based on tests performed with temperate species, although it is unknown whether the sensitivity of temperate species is representative for those of Amazonian endemic species. To address this issue, the acute toxic effect (LC(50)-96 h) of parathion-methyl was assessed on seven fish and five freshwater invertebrate species endemic to the Amazon. These data were used to compare their pesticide sensitivity with toxicity data for temperate species collected from the literature. The interspecies sensitivity was compared using the Species Sensitivity Distribution (SSD) concept. The results of this study suggest that Amazonian species are no more, or less, sensitive to parathion-methyl than their temperate counterparts, with LC(50) values ranging from 2900 to 7270 microg/L for fish and from 0.3 to 319 microg/L for freshwater arthropods. Consequently, this evaluation supports the initial use of toxicity data of temperate fish and freshwater invertebrate species for assessing the effects of parathion-methyl on Amazonian freshwater ecosystems.

Direct and indirect effects of the fungicide carbendazim on ecosystem structure and functioning were studiedor =8 weeks after application (nominal concentrations: 0, 3.3, 33, 100, and 1000 microg/L) to outdoor microcosms in Thailand. Direct effects on macroinvertebrates are discussed in detail in a separate article. The present article presents the effects on other end points and discusses the hypothesized ecologic effect chain. Negative treatment effects on the zooplankton community were only recorded for the highest carbendazim treatment (NOEC(community) = 100 microg/L). The rotifer Keratella tropica, cladocerans (Moina micrura, Ceriodaphnia cornuta, and Diaphanosoma sp.), and cyclopoid copepods were decreased or even eliminated at this treatment level. The decrease in zooplankton and macroinvertebrate abundances was accompanied by an increase in numbers of several tolerant invertebrates, presumably caused by a release from competition and predation. The death of sensitive invertebrates probably also led to an overall decreased grazing pressure because increased levels of chlorophyll-a and bloom of the floating macrophyte Wolffia sp. were noted. The increase in primary producers is discussed to be the probable cause of changes in physicochemical water conditions, eventually resulting in an anoxic water layer during the last 3 weeks of the experiment. This is likely to have resulted in decreased invertebrate abundances noted in that period. Furthermore, the decreased decomposition of Musa (banana) leaves observed 8 weeks after application is considered to be the indirect effect of a decreased microbial activity resulting from these anoxic water conditions, rather than a direct toxic effect of carbendazim.

De boktor Calamobius filum wordt nieuw gemeld voor de Nederlandse fauna. De vondst in de provincie Gelderland sluit geografisch aan op het naar het noorden en westen uitbreidende areaal in Duitsland. Calamobius filum is een van de weinige Nederlandse boktorren die zich niet in hout of kruidachtige planten, maar in grassen ontwikkelt. Er wordt ingegaan op het voorkomen in Europa en op de biologie van de soort.

To Editor, We read with great interest the paper entitled “Traits and stress: keys to identify community effects of low levels of toxicants in test systems” by Matthias Liess and Mikhail Beketov (Liess and Beketov 2011). The paper presents a new way to analyse data from microcosms and mesocosms, which the authors claim that to be more sensitive than the commonly-used principal response curves (PRC) method (Van den Brink and Ter Braak 1999). Since PRC was developed more than a decade ago, new developments in the field of analysing community responses to stress are very welcome. However, after reading the paper, we have concluded that their new method, i.e. SPEARmesocosm, may not offer the level of improvement suggested and in this letter to the editor we will briefly explain why. Both PRC and SPEARmesocosm display the time-dependent treatment effects of a toxicant. The fundamental difference between the PRC and SPEARmesocosm methods is that PRC is a multivariate statistical method and SPEARmesocosm is a univariate method. For SPEARmesocosm to work, a single index must be constructed on the basis of predictions derived from a priori knowledge of intrinsic sensitivity and life-cycle characteristics (voltinism). By contrast, PRC does not need this a priori knowledge and can work with multiple indices. In microcosm and mesocosm studies for which it was developed it is usually applied on the original taxon composition data. PRC is thus a purely statistical method for analysing empirical data derived from mesocosm and other community-level experiments. PRC partitions the observed variance in the data in time, treatment (which includes interaction with time) and residual variance (which corresponds to the differences between replicates) and summarises the variance explained by treatment and time by showing the time-dependent treatment effects in sequential (first, second, etc.) PRC diagrams. These PRC diagrams show the contrasting responses of different (groups of) taxa, very much like the contrasting response of the sensitive univoltine species and the other taxon groups as displayed in Fig. 2 of Liess and Beketov (2011). The agreement of Fig. 2 with PRC would have been even greater if the percentage change would have been plotted on a logarithmic scale. When comparing the statistical methods for analysing the data from such experiments, it is clearly critical that the same endpoints are being compared (using the same input data), otherwise the differences seen in outcomes cannot be reliably attributed to the statistical methods. We feel that the comparison made in Fig. 3 is inappropriate, the comparison is one of apples with oranges. While the PRC diagram shows the dominant response present in the whole invertebrate community, SPEARmesocosm only takes (presumed) sensitive species into account. For a proper comparison, Liess and Beketov could have performed a PRC analysis only using the sensitive univoltine taxa, which would almost certainly have yielded a diagram comparable to Fig. 3b. Probably the sub-dominant responses of the sensitive univoltine taxa would be presented by the second PRC of the original analysis. We are, unfortunately, not in the position to evaluate this since no access to the data was provided on this short time-frame, despite a request to the authors. How the second PRC is extracted and tested for significance is explained in the original PRC publication (Van den Brink and Ter Braak 1999), while Van den Brink and ter Braak (1998); Van den Brink et al. (2003) and Maccherini et al. (2007) present examples of the use of the second PRC. We acknowledge that testing the second PRC on its significance and presenting it when it is significant is not common practice. This example indicates that such an approach should be evaluated more often than it is at present. In passing we note that instead of applying PRC to the original taxon data, PRC could also have been applied to the data after aggregation to taxon clusters. This would have signalled out directly the different response of the sensitive univoltine taxa to the toxicant in comparison with the other groups. As another way of ensuring that all responses present in the data set are highlighted is to perform univariate tests at the taxon level and present the responses of all taxa for which consistent significant treatment effects are indicated. This approach is common practice and required in the evaluation of most microcosm and mesocosm studies performed for registration purposes of pesticides in Europe (SANCO 2002; De Jong et al. 2005). Such analyses would no doubt also highlight the sensitive responses at the population level as are presented by the SPEAR method. Since the data of the mesocosm experiment are not presented by Liess and Beketov (2011) in a format which allows these queries to be addressed, it is difficult to gain understanding regarding the dominance or rarity of the different taxa. All abundances provided are expressed as relative to the control, so it is unclear what the actual recorded abundances of the taxa were. We would expect that may have been somewhat low for individual taxa in the samples (total abundance around 100 individuals/sample) since the overall abundance is approximately 1,000 individuals/m2 (Fig. 1) while 0.09 m2 (4 quadrants of 15 × 15 cm2) was sampled during each sampling time. Thus the reader cannot ascertain whether Fig. 2d is based on high or low abundance values (even single individuals), which is of crucial importance in any robust evaluation of the effects on sensitive univoltine species as compared to the whole community. In order to use SPEARmesocosm for the described experiment, some species were ‘reclassified’ in terms of their sensitivity from the original SPEAR database values. Indeed, without this reclassification “differences between control and lowest concentration were […] not significant any more” (page 1,335). The authors state that reclassification was only done for two species, not explaining the non-sensitivity classification of Gammarus sp. (original Sorganic value of +0.04; Liess and Von der Ohe 2005) and the sensitive classification of Chironomidae (original Sorganic value of −0.39; Liess and Von der Ohe 2005), when a cut-off value of −0.36 is used. This suggests that one could require a different SPEARmesocosm for each new compound to be tested in future microcosm or mesocosm experiments, and thus the generality of the proposed method is at best rather questionable. The use of a single indicator of sensitivity neglects the fact that pesticides with different mode of actions can have very different toxicity profiles which is, for instance shown by Vaal et al. (2000); Escher and Hermens (2002) and Rubach et al. (2010). Since the original SPEAR sensitivity ranking is based on the AQUIRE data base (Von der Ohe and Liess 2004), this ranking is probably dominated by organophosphate compounds, as they normally dominate EC50 data sets (Rubach et al. 2010). Consequently, it can be expected that the sensitivity ranking in SPEAR will not perform as expected for compounds which are selective for different taxonomic groups than organophosphates (see Rubach et al. 2010 for a ranking). For instance, none out of the 10 invertebrate taxa that showed the largest response to a carbendazim treatment in microcosms (Cuppen et al. 2000) would be qualified as sensitive by SPEARmesocosm, while laboratory toxicity tests performed with the same or closely related species, explain the response of seven of them in at least the highest concentration tested (Van Wijngaarden et al. 1998). Since species are a priori classified as sensitive or insensitive and univoltine or multivoltine, the SPEARmesocosm indicator does not allow for unforeseen sensitivities or life cycle characteristics of taxa—a significant short-coming for micro- and mesocosm experiments, where the majority of taxa present will normally have been untested. This is, for instance, shown by Figs. 2a, c of Liess and Beketov (2011) which indicate direct effects on taxa that are classified as insensitive. Moreover, since the index focuses on sensitivity and voltinism, it also ignores indirect effects, which are a key consideration for performing microcosm and mesocosm tests (Giddings et al. 2002). Thus while we fully support the use of traits in ecotoxicology and chemical stress ecology (Van den Brink et al. 2011), we do not agree that the approach used in Liess and Beketov (2011) is an entirely appropriate approach for the evaluation mesocosm studies. However, we sincerely look forward working with Matthias Liess, Mikhail Beketov and others to improve the ecological foundation of our science through the implementation of traits-based approaches in future research.

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.

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.

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

Simulation of the increase of sorption in time is one of the options in higher tiers of pesticide regulatory leaching assessments to obtain more realistic leaching estimates. Therefore, accurate estimates of non-equilibrium sorption parameters are required as input for the pesticide leaching scenarios. Usually, non-equilibrium sorption is described with a two-site equilibrium/non-equilibrium model in which the non-equilibrium sorption is described with two parameters (i.e. the desorption rate coefficient of the non-equilibrium site and the Freundlich sorption coefficient of this site). Estimates of these parameters can be obtained with inverse modelling techniques. At the moment, there is little understanding about whether the confidence intervals provided by inverse modelling can be used as measure of the likely accuracy (i.e. how close the estimated value is to the true value) of these estimates. We set up a semi-global inverse modelling exercise for a large number of parameter sets (i.e. different pesticides) using simulated datasets. Inverse modelling of non-equilibrium parameters demonstrated decreasing accuracy of the estimates for decreasing values of the non-equilibrium sorption parameters and the equilibrium sorption coefficient. Furthermore, we found a relationship between the accuracy of a parameter estimate and its CV (coefficient of variation) provided by the inverse modelling technique. Using this relationship we calculated the likelihood of rightly or wrongly accepting or rejecting a parameter estimate as a function of this CV. We recommend to use this likelihood as the basis of communication with decision makers on how to decide on accepting or rejecting parameter estimates. Non-equilibrium pesticide sorption parameters were estimated by inverse modelling using PEST.Accuracy of the parameter estimates was analysed using simulated datasets.This accuracy decreases with decreasing values of these parameters.Accuracy of the estimates can be predicted from its PEST confidence interval.This interval can predict whether an estimate is rightly accepted for leaching assessments.

As part of the ‘Surface Waters Decision Tree’ project a new authorisation procedure for plant protection products (PPPs) has been developed. One element is a procedure for feedback of monitoring data to the authorisation holder and the PPP authorisation authority. This report describes the methodology to be adopted for this procedure. The feedback of monitoring results in the authorisation procedure consists of 3 main steps: 1. Identification and ranking of problematic substances 2. Causal analysis and composition of an Emission Reduction Plan (ERP) 3. Feedback procedure In this report, a methodology for all three steps is described. For the causal analysis within step 2, a more detailed protocol has been developed, based on realistic test cases. The format of the ERP is not defined by the Monitoring working group and therefore no part of this report. The procedure is applicable to active ingredients and metabolites of PPP, not to biocides, pharmaceuticals and (chemical) substances with other types of use.

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

In het Nederlandse oppervlaktewater worden nog vaak te hoge concentraties gewasbeschermingsmiddelen gemeten. Veel van die middelen zijn echter gewoon toegelaten voor landbouwkundig gebruik. Wageningse onderzoekers werken daarom aan betere beoordelingsmethoden bij de toelating.

In dit rapport zijn emissieroutes van gewasbeschermingsmiddelen vanuit de fruitteelt naar het oppervlaktewater en grondwater beschreven. Daarnaast is een inschatting gemaakt van de mogelijke groottes van de verschillende emissieroutes.

In dit rapport zijn emissieroutes van gewasbeschermingsmiddelen vanuit de fruitteelt naar het oppervlaktewater en grondwater beschreven. Daarnaast is een inschatting gemaakt van de mogelijke groottes van de verschillende emissieroutes.

Doordat de groeiende wereldbevolking een steeds grotere druk op natuurlijke ecosystemen legt, wordt de vraag naar een goede methode voor het beoordelen van de mogelijkheid tot herstel van een systeem steeds groter. Dit is vooral relevant voor agrarische ecosystemen welke traditioneel als functie hebben om voedsel voor de menselijke populatie te produceren. Agrarische ecosystemen leveren echter ook andere ecosysteemdiensten zoals omzettingen van nutriënten, bestuiving, het op peil houden van een bepaalde bodemkwaliteit en structuur, maar ook esthetische en recreatieve diensten, waarvan de duurzaamheid moet worden gewaarborgd.

New concerns about biodiversity, ecosystem services and human health triggered several new regulations increasing the need for sound ecotoxicological risk assessment. The PEER network aims to share its view on the research issues that this challenges. PEER scientists call for an improved biologically relevant exposure assessment. They promote comprehensive effect assessment at several biological levels. Biological traits should be used for Environmental risk assessment (ERA) as promising tools to better understand relationships between structure and functioning of ecosystems. The use of modern high throughput methods could also enhance the amount of data for a better risk assessment. Improved models coping with multiple stressors or biological levels are necessary to answer for a more scientifically based risk assessment. Those methods must be embedded within life cycle analysis or economical models for efficient regulations. Joint research programmes involving humanities with ecological sciences should be developed for a sound risk management., JRC.H.5-Rural, water and ecosystem resources

Het gebruik van bestrijdingsmiddelen voor de productie van agrarische gewassen brengt het risico met zich mee dat deze in aangrenzende waterlichamen, zoals sloten, vijvers, meren en/of beken, terecht kunnen komen. Er zijn verschillende manieren waarop bestrijdingsmiddelen in deze waterlichamen terecht kunnen komen, bijvoorbeeld door bovengrondse afstroming op hellende agrarische velden, door overwaaiing wanneer de toepassing van bestrijdingsmiddelen dichtbij wateroppervlakten plaatsvindt of door uitspoeling van bestrijdingsmiddelen naar het oppervlakte- of grondwater. Omdat bestrijdingsmiddelen zijn ontwikkeld voor het aantasten van voor gewassen schadelijke biota, kunnen deze chemische gewasbeschermingsproducten ook schadelijk zijn voor verwante (aquatische) organismen.

Het KNMI regionaal klimaat model RACMO wordt in toenemende mate gebruikt bij de detaillering van Klimaatscenario’s. Voorbeelden zijn de frequentie en intensiteit van hittegolven en de veranderingen daarin. Of te verwachten wijzigingen in het optreden van lokale neerslagextremen. In dit project zijn een aantal componenten van RACMO verder ontwikkeld. De bodemhydrologie van het model is verder verfijnd door ruimtelijke heterogeniteit in te voeren voor een aantal bodemparameters, zoals bodemtype en worteldiepte. Deze aanpassing resulteert in meer uitgesproken ruimtelijke structuren op regionale schaal.

De boktor Calamobius filum wordt nieuw gemeld voor de Nederlandse fauna. De vondst in de provincie Gelderland sluit geografisch aan op het naar het noorden en westen uitbreidende areaal in Duitsland. Calamobius filum is een van de weinige Nederlandse boktorren die zich niet in hout of kruidachtige planten, maar in grassen ontwikkelt. Er wordt ingegaan op het voorkomen in Europa en op de biologie van de soort.

Veterinary medicinal products are applied in aquaculture production for treating and preventing diseases in the cultured species. Veterinary medicines may enter the environment by effluent discharges, posing a potential risk for surrounding aquatic ecosystems. Furthermore, human health and the trade of the aquaculture produce can be negatively affected by the presence of residues of veterinary medicines in the cultured organisms. The ERA-AQUA Decision Support System was developed to estimate risks of veterinary medicinal products applied in pond aquaculture for the targeted produce, surrounding aquatic ecosystems, consumers and trade. The risk assessment is expressed by risk quotients, which are calculated by dividing the predicted exposure concentration by the predicted no effect concentration calculated for each endpoint. This report provides a mathematical description of the processes incorporated in the ERA-AQUA Decision Support System and a user’s manual.

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.

Many agricultural areas with humic-sandy and loamy-sandy soils are used also for the extraction of water for drinking-water supply. Model concepts have been developed for the fast preferential transport of plant protection products (pesticides) in such soils, e.g. by fingered and funneled flow. An inventory is given of experiments that may be suitable for the testing of preferential transport models for cultivated sandy soils (without macropores). The pesticide concentrations per depth in soil are highly variable, due to local differences in transport, adsorption and transformation. Measurements in both the subsoil and in the upper groundwater are scarce, also due to sampling problems. Suggestions are given to improve the characterisation of soil profiles and weather conditions. Sampling methods for soil and soil solution can easily miss the preferential transport pathways. The methods of pesticide analysis in soils samples are often not sensitive enough to measure concentrations relevant for groundwater quality. The present study serves as the starting point for selecting the most suitable data sets for model testing and for the design of more complete and detailed data sets in the future.

Polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs) and organochlorine insecticides (OCs) were analysed in 58 Eurasian Eagle owl (Bubo bubo) unhatched eggs collected between 2004 and 2009 in Southeastern Spain. Levels of p,p'-DDE were found to be higher than in eggs laid by other European owls in the same decade, probably due to the greater agricultural activity in our study area. Compared to other European raptors, exposure to PCBs can be considered intermediate, but low to PBDEs. Land use differences and prey availability were the rationale to divide the study area in two subareas in further assessments. Temporal trends of HCB, p,p'-DDE, s-HCH, PCBs and PBDEs were significantly different in each subarea, generally increasing over time in the Southern but decreasing or remaining stable in the Northern. On the contrary, levels of cyclodienes tended to decrease in both subareas. Dietary shifts with a greater amount of birds are suggested as a cause for increasing organochlorine loads in raptors. This may explain the increasing trend in the Southern territories. However, due to the proximity of most of these nests to Cartagena, an important industrial city, increasing environmental pollution cannot be ruled out. Although average levels of the compounds analysed are below threshold levels, 17% of the samples exceeded 400 pg g-1 ww (wet weight), the LOAEC for Total TEQs. Moreover, a negative correlation between TEQ concentrations and the metabolizable fraction of PCBs (Fprob = 0.0018) was found when TEQs values were above 10 pg g-1 ww. This could be indicative of hepatic enzymes induction in the birds exposed at higher concentrations, which are mainly breeding in the Southern subarea. These females could be suffering from Ah-receptor-related toxic effects, some of which have been related to altered bird reproduction. Finally, a significant negative correlation between p,p'-DDE levels and eggshell thickness (r = -0.469, p

In the TOXSWA (TOXic substances in Surface WAters) model volatilization of pesticides from surface water is computed because it may be an important component of the mass balance of pesticides in water bodies. Here, we briefly review the physics of air-water gas exchange relevant in this context. A new parameterization of volatilization is proposed. This new TOXSWA parameterization would take into account key physical aspects of the air-water gas exchange process, while still fitting into the TOXSWA philosophy. It is recommended to cast the new parameterization into a micrometeorological framework, based on two atmospheric resistances and one aqueous resistance against gas transport. In this context, the dimensionless Henry coefficient is a crucial characteristic of the pesticides and determines whether atmospheric properties as modelled by the atmospheric resistances exert the main dynamic control on air-water gas exchange or the aqueous properties and resistance. Most pesticides will be subject to atmospherically controlled volatilization.

Het KNMI regionaal klimaat model RACMO wordt in toenemende mate gebruikt bij de detaillering van Klimaatscenario’s. Voorbeelden zijn de frequentie en intensiteit van hittegolven en de veranderingen daarin. Of te verwachten wijzigingen in het optreden van lokale neerslagextremen. In dit project zijn een aantal componenten van RACMO verder ontwikkeld. De bodemhydrologie van het model is verder verfijnd door ruimtelijke heterogeniteit in te voeren voor een aantal bodemparameters, zoals bodemtype en worteldiepte. Deze aanpassing resulteert in meer uitgesproken ruimtelijke structuren op regionale schaal.

Om duurzame gewasbescherming te bereiken heeft de overheid in de nota Duurzame gewasbescherming meerdere doelen geformuleerd voor het oppervlaktewater. Eén van de doelen was om het oppervlaktewater in 2010 ten opzichte van 1998 95% minder met gewasbeschermingsmiddelen te belasten. Daarnaast mocht het oppervlaktewater in 2010 geen concentraties van gewasbeschermingsmiddelen bevatten boven het niveau van het Maximaal Toelaatbaar Risico (MTR). Uit de evaluatie blijkt dat op ongeveer 50% van de bemeten locaties boven het MTR zijn aangetroffen. Bij de kasteelten was de afname 68%. In zowel de kasteelten als de vollegrondteelten wordt het milieu vooral door een beperkt aantal stoffen belast. In de open teelten is verwaaiing van spuitvloeistof (drift) nog steeds de belangrijkste route voor deze stoffen; in de kasteelten zijn dit lozing van gietwater en drainage. Aanbevolen wordt in de vollegrondteelten nog sterker in te zetten op driftreducerende maatregelen, of alternatieve stoffen te gebruiken voor de meest toxische stoffen. Het gerapporteerde aantal knelpunten voor de drinkwaterwinning is beperkt afgenomen, iets meer dan 30%.

Many agricultural areas with humic-sandy and loamy-sandy soils are used also for the extraction of water for drinking-water supply. Model concepts have been developed for the fast preferential transport of plant protection products (pesticides) in such soils, e.g. by fingered and funneled flow. An inventory is given of experiments that may be suitable for the testing of preferential transport models for cultivated sandy soils (without macropores). The pesticide concentrations per depth in soil are highly variable, due to local differences in transport, adsorption and transformation. Measurements in both the subsoil and in the upper groundwater are scarce, also due to sampling problems. Suggestions are given to improve the characterisation of soil profiles and weather conditions. Sampling methods for soil and soil solution can easily miss the preferential transport pathways. The methods of pesticide analysis in soils samples are often not sensitive enough to measure concentrations relevant for groundwater quality. The present study serves as the starting point for selecting the most suitable data sets for model testing and for the design of more complete and detailed data sets in the future.

Om duurzame gewasbescherming te bereiken heeft de overheid in de nota Duurzame gewasbescherming meerdere doelen geformuleerd voor het oppervlaktewater. Eén van de doelen was om het oppervlaktewater in 2010 ten opzichte van 1998 95% minder met gewasbeschermingsmiddelen te belasten. Daarnaast mocht het oppervlaktewater in 2010 geen concentraties van gewasbeschermingsmiddelen bevatten boven het niveau van het Maximaal Toelaatbaar Risico (MTR). Uit de evaluatie blijkt dat op ongeveer 50% van de bemeten locaties boven het MTR zijn aangetroffen. Bij de kasteelten was de afname 68%. In zowel de kasteelten als de vollegrondteelten wordt het milieu vooral door een beperkt aantal stoffen belast. In de open teelten is verwaaiing van spuitvloeistof (drift) nog steeds de belangrijkste route voor deze stoffen; in de kasteelten zijn dit lozing van gietwater en drainage. Aanbevolen wordt in de vollegrondteelten nog sterker in te zetten op driftreducerende maatregelen, of alternatieve stoffen te gebruiken voor de meest toxische stoffen. Het gerapporteerde aantal knelpunten voor de drinkwaterwinning is beperkt afgenomen, iets meer dan 30%.

In het Nederlandse oppervlaktewater worden nog vaak te hoge concentraties gewasbeschermingsmiddelen gemeten. Veel van die middelen zijn echter gewoon toegelaten voor landbouwkundig gebruik. Wageningse onderzoekers werken daarom aan betere beoordelingsmethoden bij de toelating.

This manual describes the PEARLNEQ v5 software package . This package can estimate long-term sorption parameters using results of aged-sorption studies with soil, using a submodel for sorption and transformation that is identical to the submodel used for that purpose in the FOCUS_PEARL v3.3.3. The submodel assumes two types of sorption sites: equilibrium sites and non-equilibrium sites. The sorption isotherms for both sites are described with Freundlich equations. The mathematical equations describing the submodel are solved via a FORTRAN programme. An additional FORTRAN programme generates the necessary input files for the PEST optimisation package. Instructions are given how to obtain optimized parameters using an example dataset and how to obtain parameters using your own data.

Dit onderzoek is uitgevoerd in opdracht van het ‘Hoogheemraadschap De Stichtse Rijnlanden’ (HDSR), i.s.m. Waternet, gemeente Woerden, STOWA en Team Invasieve Exoten. In deze studie wordt onderzocht wat de impact van de, uit de literatuur, twee meest veelbelovende beheers/bestrijdingsmaatregelen van invasieve kreeften is op een populatie rode Amerikaanse rivierkreeften (Procambarus clarkii). De twee maatregelen bestaan uit het wegvangen van adulte dieren en het inzetten van predatore vis om de aantallen van de jonge dieren te controleren. In dit experiment is gekozen voor paling als roofvis omdat dit de meest voor de hand liggende keuze was gezien het beheersgebied van HDSR en Waternet. Echter deze combinatie geeft in dit experiment niet de duidelijke resultaten die vooraf verwacht werden. Dit geeft in ieder geval aan dat de impact van predatore paling op kreeftenpopulaties niet sterk genoeg was om binnen 81 dagen duidelijke effecten te sorteren of dat deze impact van andere factoren (die niet of niet afdoende in de test vertegenwoordigd waren) afhankelijk is.

De meeste baggerspecie, inclusief licht verontreinigde baggerspecie die vrijkomt bij onderhoud van watergangen, wordt verspreid op landbouwpercelen. Het in dit rapport beschreven onderzoek is opgezet om op praktijkschaal na te gaan of op dit moment de praktijk van het verspreiden van licht verontreinigde bagger meetbare effecten heeft veroorzaakt en aan te geven wat er in de toekomst kan worden verwacht bij voortzetting van de huidige praktijk. De belangrijkste conclusie van het onderzoek is dat in de onderzochte klei- en veengebieden de praktijk van verspreiden van baggerspecie niet heeft geleid tot een sterke achteruitgang van de bodem. Achteruitgang is echter wel mogelijk als de praktijk van verspreiden meer opschuift in de richting van de kwaliteit die maximaal is toegestaan. Op basis van het onderzoek worden diverse aanbevelingen voor het beleid gemaakt.

In the TOXSWA (TOXic substances in Surface WAters) model volatilization of pesticides from surface water is computed because it may be an important component of the mass balance of pesticides in water bodies. Here, we briefly review the physics of air-water gas exchange relevant in this context. A new parameterization of volatilization is proposed. This new TOXSWA parameterization would take into account key physical aspects of the air-water gas exchange process, while still fitting into the TOXSWA philosophy. It is recommended to cast the new parameterization into a micrometeorological framework, based on two atmospheric resistances and one aqueous resistance against gas transport. In this context, the dimensionless Henry coefficient is a crucial characteristic of the pesticides and determines whether atmospheric properties as modelled by the atmospheric resistances exert the main dynamic control on air-water gas exchange or the aqueous properties and resistance. Most pesticides will be subject to atmospherically controlled volatilization.

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.