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PostersAgriculture and Food, Crop Protection2021

A Novel Approach for Estimating Flow During Submerged Tile Conditions

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ASABE 2021 Annual Meeting, July 2021

Session:  Natural Resource and Environmental Systems (#23 Drainage Group)

Abstract: Accurate tile flow rate and flow volume estimates are critical to estimating subsurface nutrient runoff. Efforts have been made to improve the accuracy and ease of flow estimates during free flow conditions using water level control structures paired with weirs and water level instrumentation. However, in fields experiencing submerged tile conditions, few options exist for estimating tile flow beyond installing velocity-based flow instrumentation, which is often cost-prohibitive. This work proposes a method for estimating flow rate and volume during submerged tile conditions by taking into account flow proportion of monitored and unmonitored tile laterals based on field flow lines, assessing the proportion of tile main runoff attributed to each lateral using historical free-flowing event data, and applying the new lateral flow proportions in conjunction with weir equations to produce a modified flow calculation. This method is applied to a sample field research site with 45 total tile laterals (18 monitored, 27 unmonitored) using water level data for flow events between 2017-2020.

Authors:  Patricia Paulausky, Farah Abi-Akar, Russell Krueger (Waterborne Environmental), Laura Gentry (Illinois Corn Growers Association), Gregory Goodwin (Waterborne Environmental).  ASABE 2021 Annual International Meeting.

Problem Definition of a Harmonised Framework for Spatially Distributed Leaching Modelling (SDLM) of Pesticides

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Session:  Measuring, Monitoring and Modelling of Pesticide Fate and Mitigation in a Regulatory Context

Abstract:  Spatially distributed leaching modelling (SDLM) of pesticides is a methodology to estimate the leaching potential of plant protection products over an extensive spatial scale such as national or European. It is described as a higher tier in the current European Guidance for groundwater risk assessment. Whereas this option is an integral part of the tiered assessment scheme only little guidance is provided on how to conduct such spatial assessments with SDLM. Guidance on how to perform such leaching assessments is therefore needed, as well as version control for high-resolution spatial databases for the EU. It was therefore decided to establish a working group under the umbrella of the SETAC Environmental Monitoring Advisory Group on Pesticides (SETAC EMAG-PEST). This document describes the aim and scope of the work to be performed by this working group. The main products of the working group will be a harmonised modelling framework including the data needed to run these models, and documents describing the use of the framework in regulatory assessments. The framework will serve two different Tiers of the groundwater risk assessment scheme, i.e. Tier-3b and Tier-4. At Tier-3b, the framework will deliver the same exposure assessment goal as currently used in FOCUS groundwater, i.e. the 80th-spatial and temporal percentiles of the leaching concentration at 1-m depth. This exposure assessment goal is considered a conservative estimate of the real groundwater concentration. To ensure consistency of the tiered approach, the modelling framework will support all parameter refinements carried out at Tier-2. At Tier-4, the measured groundwater concentration in groundwater wells is assessed. The modelling framework plays a crucial role for the selection of vulnerable regions in which to install monitoring wells. It can also be used to demonstrate whether existing groundwater monitoring studies have been carried out at locations that are sufficiently vulnerable in view of the existing FOCUS exposure assessment goal. The modelling framework will, however, not simulate the actual concentration in the groundwater wells, because additional processes occur between 1 m depth and the position of the groundwater wells. The Working Group will consist of members from academia, regulators and industry. It will consist of a Steering Committee, a subgroup on spatial data and a subgroup on modelling. The Working Group will deliver two years after the start of the project.

Authors: Bernhard Jene (BASF), Aaldrik Tiktak (PBL), Abdul Ghafoor (KEMI), Anton Poot (CTGB), Erik van den Berg (Wageningen University), Cornelis Hoogeweg (Waterborne), Michael Klein (Fraunhofer IME), Michael Stemmer (AGES), Paul Sweeney (Syngenta), Robin Sur (Bayer AG)

PostersCrop Protection2021

Impact of Climate Change on the Relevance of OECD Crosswalks

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Session:  Extended submission 3 – Environmental chemistry and exposure assessment: analysis, monitoring, fate and modeling

Abstract:  Climate change studies confirm that the earth is warming up and that shifts in rainfall patterns is occurring. Various computer models predict that Earth’s average temperature will rise between 1.8° and 4.0° Celsius (3.2° and 7.2° F). Consequently, these warmer temperatures will cause a higher rate of evaporation, resulting in a predicted increase of average global rainfall by 3-5%. Under OCED guidance, TFD studies conducted in one country can be applicable to other countries if the characteristics of overlapping ecoregions are the same. These assessments are conducted using the OECD ENASGIPS tool. If these characteristics change, so will the similarity assessment and therefore the potential relevance of TFD sites. With increase rainfall, TFD sites in the Southeastern US, which typically have few similar areas, may become more relevant because other areas are getting wetter. Likewise, TFD sites in arid ecoregions may see a decrease in similarity scores. In this presentation we show that TFD studies in arid regions in the US remain relevant for foreseeable future.The objective of this assessment was to determine if climate change will impact the relevance of TFD studies and OECD ENASGIPS crosswalks ecoregion similarity scores. Specifically, we were interested in determining if ecoregions overlapping TFD sites remain the same over time in terms of precipitation, temperature, and ecoregion similarity. Both statistical analysis and ecoregion crosswalk assessments were conducted. In this presentation we will focus on an arid in California’s Central Valley using the intermediate IPCC RCP4.5 and worse case RCP8.5 climate change scenarios. Results indicate that under moderate climate change scenario the arid ecoregion has an increase in the number of similar ecoregion over time but a decrease is observed under the worse case scenario. In the short-term, 30 to 40 years, TFD studies are not predicted to see an impact by of climate change and data obtained from these TFD studies can be used for registration and reregistration of pesticides for the foreseeable future.

Authors:  Cornelis Hoogeweg, Amy Ritter, Raghu Vamshi, Dean Desmarteau (Waterborne).  SETAC Europe 2021.

PostersCrop Protection2021

Identification of Patterns in Mesocosm Data: An Analysis of Untreated Control Ecosystems Across Multiple Studies

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Session: Effect Modelling for Regulatory Environmental Risk Assessment of Chemicals: Where Are We and What Comes Next?

Abstract: For risk assessment, experimental mesocosms provide valuable insights into the complex responses of aquatic ecosystems to stressors. Similarly, aquatic systems models (ASMs) represent food web interactions in an aquatic species community and interactions with abiotic environmental conditions. In the context of a study to simulate mesocosms using ASMs, an analysis of control mesocosm data was conducted to identify patterns in temporal dynamics in the species communities. Control data from six mesocosm studies were anonymized, collated, and characterized using visual and statistical analyses. The data were generated during studies conducted in 2016, 2018 and 2019 by MESOCOSM GmbH. During these studies, physical parameters of temperature, oxygen, pH, water level and conductivity were measured over the study duration. Nitrate, ammonium, and phosphate concentrations and water hardness were measured prior to the beginning of each study. Additionally, weekly samples were collected for taxon and species abundance evaluation. The resulting dynamics of phytoplankton, periphyton, macrophytes, zooplankton and macroinvertebrates were analyzed for each study data set and across studies. Correlation matrices were constructed and used to examine the data and identify consistent patterns of biotic and abiotic interactions. The trends observed within and across the studies show considerable temporal variability in species composition and abundance. The characterization and understanding of similar and repeated temporal patterns in the untreated aquatic mesocosms is an important foundation for the simulation of mesocosm studies using ASMs. We provide perspectives on the challenges associated with variability observed in mesocosm controls, and offer possible explanation and insights for managing these challenges in modeling.

Authors: Farah Abi-Akar (Waterborne), Amelie Schmolke (Waterborne), Peter Ebke (Mesocosm GmbH), Jürgen Schmidt (Mesocosm GmbH), Nika Galic (Syngenta), Steven Bartell (Cardno), Isabel O’Connor (EBP), Simon Spycher (EBP), Nele Schuwirth (EAWAG), Tido Strauss (Gaiac), Damian Preziosi (Integral), Robert Pastorok (Integral), Roman Ashauer (Syngenta).  SETAC Europe 2021.

PresentationsCrop Protection2021

Modelling Ecosystems in Mesocosms: A Ring Study Approach With Four Aquatic Systems Models

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Session: Effect Modelling for Regulatory Environmental Risk Assessment of Chemicals: Where Are We and What Comes Next?

Abstract:  Aquatic systems models (ASMs) represent food-web interactions in an aquatic community and interactions with environmental conditions. Ecological models, including ASMs, are valuable tools in pesticide risk assessments because they can be applied to a range of biotic and abiotic conditions, as well as to a variety of exposure scenarios which would be impractical to test empirically. Four ASMs (Streambugs, AQUATOX, CASM, and StoLam with STREAMcom) that have been developed, published and applied in pesticide risk assessments and other contexts are the subjects of this ring study. Model inputs and outputs are compared among the ASMs, using mesocosm data generated and provided by MESOCOSM GmbH. The ASM ring study includes: a) analysis and preparation of mesocosm control and treatment data, b) definition of the food web represented across ASMs, c) parameterization of the ASMs, d) calibration of the ASMs to mesocosm control data, e) validation of the calibrated ASMs against mesocosm control data not used in the calibration, f) calibration of the ASMs to mesocosm treatment data. All steps are documented in detail, following the recommendations of the good modeling practice. We will present methods and results of the steps a) – d). We outline an approach for defining a mesocosm food web that can be represented by multiple ASMs, and the parameterization and calibration of the ASMs to the available mesocosm data. The approach provides important insights into the strengths and limitations of different ASMs for this particular modelling exercise through comparison of the model outputs with each other and with empirical data. In the next steps of the ring study, we will evaluate the ASMs using independent mesocosm data from the same test site, and simulate treatment effects for an example pesticide.

Authors: Amelie Schmolke (Waterborne), Nika Galic (Syngenta), Steven Bartell (Cardno), Isabel O’Connor (EBP), Simon Spycher (EBP), Nele Schuwirth (EAWAG), Tido Strauss (Gaiac), Damian Preziosi (Integral), Robert Pastorok (Integral), Peter Ebke (Mesocosm GmbH), Jürgen Schmidt (Mesocosm GmbH), Farah Abi-Akar (Waterborne), Jennifer Collins (Waterborne), Roman Ashauer (Syngenta).  SETAC Europe 2021.

PresentationsCrop Protection2020

An Overview of Key Features of Population Models and Their Relevance for Ecological Risk Assessment

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Session Title: 5.06 – Environmental Effects Modeling: Advances in Development and Application of Effects Models in Environmental Risk Assessment
SciCon2 5.06.01

Abstract:

The last two decades have seen substantial advances in the development of population models for the ecological risk assessment (ERA) of chemicals. These include guidance on systematic and consistent model creation and documentation, model evaluation and testing, and choosing models of appropriate complexity to address different types of risk assessment questions. A growing collection of case studies has clearly demonstrated how such models can inform risk assessment and risk management decisions, and slowly but surely there are indications that the acceptance of population models for ERA will continue to increase. Nevertheless, there remain misconceptions about population models for ERA, including confusion regarding differences among types of model formalization (e.g., differential equation, matrix or agent-based models), uncertainty surrounding the implications of including or ignoring different aspects of reality in the models, as well as a lack of consensus on the role that the models should play in the ERA process. We provide an overview of the key features that may be included in population models to inform ERAs. They include density dependence, spatial variability, external drivers, stochasticity, life history, behavior, energetics and how exposure and effects are integrated in the models. We consider why these features are relevant for ERA and how they can be incorporated into three broadly defined population model categories: unstructured, structured, and agent-based. We show that nearly all features can be included in all model categories, but some features are more or less easily incorporated in certain model types. Using a previously published database of population models, we assessed the frequency with which each of the key features has been included so far in the different model categories. We show that some features have been more strongly associated with a certain model category. The aims of the overview are to help model developers and model evaluators assess the extent to which a model and its features are fit for purpose and to increase the consistency and transparency of population models used for ERA.

C. Accolla (University of Minnesota), M. Vaugeois (University of Minnesota), V. Grimm (Helmholtz Centre for Environmental Research – UFZ), A. Schmolke (Waterborne), A. Moore (University of Minnesota), P. Rueda-Cediel  (University of Minnesota), V. Forbes (University of Minnesota)

An Overview of Key Features of Population Models and Their Relevance for Ecological Risk Assessment. SciCon2 5.06.01, SETAC 2020 Virtual Meeting.

PresentationsCrop Protection2020

Assessing the Risks of Pesticides to Terrestrial Threatened and Endangered Species: Opportunities to Refine Risk Assessments for Listed Terrestrial Plants

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Session Title: 5.04 – Endangered Species Assessments for Pesticides
SciCon2 5.04.14

Abstract:

There is a continuing need to develop improved procedures and tools for assessing pesticide risks to threatened and endangered (i.e., listed) species in the United States. As part of meeting this challenge, the TERrestrial Endangered Species Assessment (TERESA) model was developed following a tiered approach to efficiently evaluate potential pesticide exposures and risks to listed terrestrial species. The terrestrial plant version of TERESA includes the ability to evaluate risks to listed plant species based on direct effects or potential indirect pathways (e.g., effects to insect pollinators or obligate symbionts). For species that are not screened out in the first tiers of the analysis in TERESA, various refinements can be conducted to better characterize risk using information about the species and relevant product use patterns. We conducted refined case studies for a subset of listed terrestrial plant species potentially exposed to a representative insecticide. Multiple lines of evidence were evaluated including refined spatial exposure estimates based on product use information and species life history and characteristics that may influence exposure potential. Factors considered in these analyses include local use conditions, application rates and methods, temporal relationships between species and application timing and species habitat associations. Given the low direct toxicity of this pesticide to terrestrial plants, the focus is on illustrating an approach to evaluate risk to biological features upon which the listed plant species depends. The case studies highlight the importance of bringing together the most reliable and relevant information to reduce uncertainty and improve our understanding of pesticide risk to listed species.

M. Kern (Balance EcoSolutions LLC), N. Green (Waterborne), N. Snyder (Waterborne), D. Moore (Intrinsik), S. Teed (Intrinsik), C. Priest (Intrinsik), H. Rathjens (Stone Environmental), M. Winchell (Stone Environmental), T. Blickley (Eurofins EAG Agroscience Services LLC)

Assessing the Risks of Pesticides to Terrestrial Threatened and Endangered Species: Opportunities to Refine Risk Assessments for Listed Terrestrial Plants. SciCon2 5.04.14, SETAC 2020 Virtual Meeting.

PresentationsCrop Protection2020

A Tiered Approach to Efficient Refinement of Aquatic Exposure Assessments for Endangered Species

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Session Title: 5.04 – Endangered Species Assessments for Pesticides
SciCon2 5.04.08

Abstract:

Quantitative pesticide exposure and risk modeling is a powerful tool to effectively and efficiently make the important distinction between threatened and endangered species that are likely to be and not likely to be adversely affected (LAA and NLAA, respectively) as a resulted of a pesticideís labeled uses. To achieve efficiency and transparency in such assessment for aquatic species, progressive steps in exposure modeling are needed that employ the best available datasets and scientific approaches to introduce meaningful and substantial refinements. We have developed a multi-tiered approach for aquatic exposure modeling designed to meet these requirements for national scale endangered species risk assessments. The approach begins with Tier 1 which is highly conservative and represents potential high-end exposure for all species. Tier 1 accounts for a wide range of potential use patterns, cropping scenarios, application dates, and weather conditions. At Tier 2, much greater relevance of the exposure estimates for each species is achieved by accounting for the spatial overlap between pesticide exposure scenarios and species ranges and critical habitats. In Tier 2, two additional refinement steps are incorporated into the exposure modeling. The first refinement accounts for potential pesticide use sites, or percent cropped area (PCA), in estimating exposure concentrations in multiple static and flowing aquatic habitat types. PCA for large numbers of relevant water bodies within a species range are analyzed using GIS datasets and processing techniques. The second refinement step in Tier 2 is based on best available pesticide usage data. Usage data are analyzed probabilistically to generate an ensemble of pesticide usage scenarios across the US and overlaid with species ranges. This pesticide usage data refinement step results in quantitative pesticide exposure probability distributions that are then incorporated into risk assessment decisions. The two-tier methodology developed is an efficient, effective, and transparent process using best available data and scientific analysis methods that helps guide a risk assessor to making NLAA/LAA decisions in national endangered species risk assessments.

M. Winchell (Stone Environmental), H. Rathjens (Stone Environmental), S. Castro-Tanzi (Stone Environmental), J. Dunne (Stone Environmental), N. Snyder (Waterborne), P. Havens (Corteva Agriscience)

A Tiered Approach to Efficient Refinement of Aquatic Exposure Assessments for Endangered Species. SciCon2 5.04.08, SETAC 2020 Virtual Meeting.

PresentationsCrop Protection2020

Assessing the Risk of Pesticides to Threatened and Endangered Species: Developments of Process and Tools

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Session Title: 5.04 – Endangered Species Assessments for Pesticides
SciCon2 5.04.02

Abstract:

In the United States, registration of a pesticide is considered a Federal action and, as such, requires a review of potential impacts to threatened and endangered species (listed species) and their designated critical habitats under the Endangered Species Act (ESA). There are over 1600 listed species in the United States, multiple use sites for each pesticide active ingredient, and three agencies (the US Environmental Protection Agency (EPA), Fish and Wildlife Service (FWS), and National Marine Fisheries Service (NMFS), collectively ìthe Agenciesî) involved in each assessment. Thus, an endangered species risk assessment (ESRA) for a pesticide is an enormous undertaking. Although there has been progress towards developing more efficient and scientifically defensible approaches for pesticide ESRAs, continuous improvement in these methods is required. This presentation describes investigations into the development of ever more efficient, transparent, reproducible, and sustainable ESRA processes for pesticides, including the development of innovative and user-friendly new tools. We illustrate these developments with case studies involving representative insecticide, herbicide and fungicide chemistries. Subsequent presentations in this session will describe many of the tools and approaches that were developed as part of this work.

D. Moore (Intrinsik), T. M. Blickley (Corteva Agriscience), L. Brewer (Compliance Services International), A. Frank (Compliance Services International), J. Giddings (Compliance Services International), P. Havens (Corteva Agriscience), M. Kern (Balance EcoSolutions LLC), C. Priest (Intrinsik), B. McGaughey (Compliance Services International), H. Rathjens (Stone Environmental), N. Snyder (Waterborne), R.S. Teed (Intrinsik), M. Whinchell (Stone Environmental)

Assessing the Risk of Pesticides to Threatened and Endangered Species: Developments of Process and Tools. SciCon2 5.04.02, SETAC 2020 Virtual Meeting.

PresentationsCrop Protection2020

Coupling PRZM with SWAT for Ecological Risk Assessment of Agricultural Pesticides

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Session Title: 4.03 – Exposure: Processes and Approaches for Estimating Environmental Exposures
SciCon2 4.03.10

Abstract:

Ecological risk assessment for the regulatory compliance of agricultural pesticides requires determination of potential exposure levels in receiving water bodies to which aquatic organisms may be exposed. Modeling and monitoring approaches are key methods used in determining pesticide exposure levels, length and frequency of occurrences. In this study, we present a modeling framework involving a conjunctive use of the field-scale PRZM and watershed-scale SWAT environmental models. The use of PRZM-SWAT modeling framework allowed to leverage PRZM is detailed field-level representation of pesticide fate and transport processes and SWAT is key hydrological and biogeochemical attenuation processes between edge of field losses and loss in water moving from the field into surface water networks. The PRZM-SWAT modeling framework was calibrated using a Monte Carlo approach to stream flow and a 4-, 7-, 21-, 30-, and 60-day maximum annual rolling average exposure durations, that are of significance to the ecological risk assessments. The performance of the model was evaluated using 8-year monitoring of atrazine data and stream flow from a high use-intensity, headwater watershed in Missouri. This presentation will describe the modeling framework, calibration approaches, and results of the modeling performances.

L. Ghebremichael (Syngenta), W. Chen (Syngenta), A. Jacobson (Waterborne), C. Roy (Waterborne)

Coupling PRZM With SWAT for Ecological Risk Assessment of Agricultural Pesticides. SciCon2 4.03.10, SETAC 2020 Virtual Meeting.