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Solitary bees provide an important ecological and agricultural service by pollinating both wild plants and crops, often more effectively than honey bees. In the context of worldwide pollinators' declines, it is important to better understand the functioning of populations under multiple stressors at larger spatial and temporal scales. Here we propose building a detailed, spatially-explicit agent-based model of one of the best-studied species of solitary bees, Osmia bicornis L. In this Formal Model, we review various aspects of O. bicornis biology and ecology in detail and provide descriptions of their planned implementations in the model. We also discuss the model gaps and limitations, as well as inclusions and exclusions, allowing a dialogue with the reviewers about the model's design.The ALMaSS model of O. bicornis aims to provide a realistic and detailed representation of O. bicornis populations in space and time in European agricultural landscapes. The model will be a part of the Animal, Landscape and Man Simulation System (ALMaSS); thus will be able to utilise a highly detailed, dynamic ALMaSS landscape model. It will consider the behaviour of all bee life stages daily and use state transitions to allow each individual to decide their behaviour. The development of egg-to-pupa stages in the nest will be temperature-driven. Adult bees, after they emerge from the nest in spring, will interact with the environment. They will be able to search for suitable nesting locations, provision their brood cells with pollen and reproduce. Modelled females will balance offspring size and number following the optimal allocation theory, but local environmental factors will modify their actual parental investment decisions. The model will include the daily mortality rate for the egg-to-pupa stages, overwintering mortality, and background mortality outside the nest. We will also consider the risk of open-cell parasitism as increasing with the time the brood cell is open.With the level of detail suggested, the model will be able to simulate population-level dynamics in response to multiple factors at the landscape scale over long periods. The European Food Safety Authority (EFSA) has suggested O. bicornis as a model organism for non-Apis solitary bees in the pesticide risk assessment scheme. Therefore, we hope our model will be a first step in building future landscape risk assessments for solitary bees.

A limitação natural de pragas é um serviço de ecossistema que deve ser promovido nos sistemas agrícolas, já que pode ser usada como alternativa, ou complementarmente, à aplicação de pesticidas. Consiste no consumo das pragas pelos seus inimigos naturais e pode ser promovida através do estabelecimento de componentes paisagísticas que forneçam, a estes inimigos das pragas, alimento alternativo e refúgio, para além da aplicação de práticas agrícolas sustentáveis. No entanto, o delineamento de uma estratégia eficaz de limitação natural de pragas está dependente da caracterização detalhada dos comportamentos dos animais que fazem parte dessa cadeia trófica, nomeadamente, das pragas e dos seus predadores, o que pode ser feito através de simulações computacionais. Neste contexto, e no âmbito do projeto OLIVESIM, estamos a construir um sistema de modelos para simular a biologia e o comportamento de duas espécies de artrópodes (1) a mosca-da-azeitona, Bactrocera oleae (Rossi), praga chave da oliveira, e (2) a aranha de solo, Haplodrassus rufipes (Lucas), um dos potenciais predadores da praga, e as suas interações com a paisagem selecionada para realizar este estudo, localizada na região de Trás-os-Montes (Mirandela, Portugal) e caracterizada fundamentalmente por olival tradicional. Para isso, está a ser utilizado o sistema ALMaSS (Animal, Landscape and Man Simulation System), que recebe inputs diários de variáveis climáticas e também de ações de gestão agrícola, e que é calibrado com dados sobre abundância quantitativa e qualitativa de animais. Neste simpósio focamo-nos nestes dois modelos, mostrando também o estado atual deste trabalho. Natural pest control is an ecosystem service that should be promoted in agricultural systems, as it can be used as an alternative or complementary to pesticide application. It consists in increasing the populations of natural pest enemies by establishing landscape components that provide them with alternative food and refuge, and by applying sustainable agricultural practices. However, the design of an effective strategy for natural pest control depends on the detailed characterization of the behaviour of animals that are part of this trophic chain, namely pests and their predators, which can be done through computational simulations. In this context, and in the scope of project OLIVESIM, we are building a system of models to simulate the biology and behaviours of two species (1) the olive fly, Bactrocera oleae (Rossi), key pest of the olive tree, and (2) a ground spider, Haplodrassus rufipes (Lucas), one of the potential predators of the pest, and their interactions with the landscape selected to carry out this study, located in the region of Trás-os-Montes (Mirandela, Portugal) and characterized primarily by traditional olive groves. For this, the ALMaSS (Animal, Landscape and Man Simulation System) system is being used, which receives daily inputs of climatic variables and agricultural management actions, and which is calibrated with data on quantitative and qualitative abundance of animals. In this symposium, we focus on the models for these two animal species, showing the current state of this work. info:eu-repo/semantics/publishedVersion

A conceptual framework was developed by a working group of the Scientific Committee of the European Food Safety Authority (EFSA) to guide risk assessors and risk managers on when and how to integrate ecological recovery and resilience assessments into environmental risk assessments (ERA). In this commentary we advocate that a systems approach is required to integrate the diversity of ecosystem services (ES) providing units, environmental factors, scales, and stressor-related responses necessary to address the context dependency of recovery and resilience in agricultural landscapes. A future challenge in the resilience assessment remains to identify the relevant bundles of ecosystem services provided by different types of agroecosystem that need to be assessed in concert. Integr Environ Assess Manag 2018;14:586-591. (c) 2018 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC)

EFSA performs environmental risk assessments (ERAs) for single potential stressors such as plant protection products, genetically modified organisms and feed additives and for invasive alien species that are harmful for plant health. In this risk assessment domain, the EFSA Scientific Committee recognises the importance of more integrated ERAs considering both the local and landscape scales, as well as the possible co-occurrence of multiple potential stressors that fall under the remit of EFSA, which are important when addressing ecological recovery. In this scientific opinion, the Scientific Committee gathered scientific knowledge on the potential for the recovery of non-target organisms for the further development of ERA. Current EFSA guidance documents and opinions were reviewed on how ecological recovery is addressed in ERA schemes. In addition, this scientific opinion is based on expert knowledge and data retrieved from the literature. Finally, the information presented in this opinion was reviewed by experts from the relevant EFSA Panels, European risk assessment bodies and through an open consultation requesting input from stakeholders. A conceptual framework was developed to address ecological recovery for any assessed products, and invasive alien species that are harmful for plant health. This framework proposes an integrative approach based on well-defined specific protection goals, scientific knowledge derived by means of experimentation, modelling and monitoring, and the selection of focal taxa, communities, processes and landscapes to develop environmental scenarios to allow the assessment of recovery of organisms and ecological processes at relevant spatial and temporal scales.

Current EU regulatory risk assessment allows application of pesticides provided that recovery of non-target arthropods in-crop occurs within a year. Despite long-established theory of source sink dynamics, risk assessment ignores depletion of surrounding populations and typical field trials are restricted to plot-scale experiments. Here, we use agent-based modelling of 2 contrasting invertebrates, a spider and a beetle, to assess how area of pesticide application and environmental half-life (DT50) affect the assessment of recovery at the plot scale and impact the population at the landscape scale. Small-scale plot experiments were simulated for pesticides with different application rates and DT50s. The same pesticides were then evaluated at the landscape scale (10 x 10 km) assuming continuous year-on-year usage. Our results show that recovery time estimated from plot experiments is a poor indicator of long-term population impact at the landscape level and that the spatial scale of pesticide application strongly determines population-level impact. This raises serious doubts as to the utility of plot-recovery experiments in pesticide regulatory risk assessment for population-level protection. Predictions from the model are supported by empirical evidence from a series of studies carried out in the decade starting in 1988. The issues raised then can now be addressed using simulation. Prediction of impacts at landscape scales should be more widely used in assessing the risks posed by environmental stressors.

Manganese is a magnetic resonance imaging (MRI) contrast agent for small animals that can provide a blood-flow-independent measure of neuronal activation. Established Mn MRI methods have limited ability to measure concentrations of Mn or details of its distribution in vivo, which limits their experimental power. Positron emission tomography (PET) can measure quantitative distributions in vivo in small animals of positron-emitting radionuclides such as Mn-52, although has poorer spatial resolution than MRI. Autoradiography (AR) can also measure quantitative distributions of Mn-52, in ex vivo brain tissue, with spatial resolution similar to MRI. This work has three primary goals: to develop and characterize Mn-52 as a radionuclide for PET in phantoms and in small animals, to develop a quantitative MRI method for measuring Mn concentration in the brain of small animals, and to validate the MRI results by comparisons with AR and PET. Mn-52 was produced by proton irradiation of natural Cr foil, isolated by column chromatography, and used as a PET tracer for the first time in phantoms and in vivo in rats. Mn-52 phantom image quality metrics were similar to F-18, an established PET radionuclide. After systemic administration in rats, Mn-52 accumulation was seen in bones, but little was seen in the brain, due to the blood-brain barrier. Direct injection into the lateral ventricle effectively delivers Mn-52 throughout the rat brain. Mn-52 AR images were acquired and used for comparison with MRI. MRI R1 relaxation rate maps of rat brain were acquired using a radiofrequency field strength independent inversion recovery Look-Locker sequence, and used to generate relaxation rate change and Mn concentration maps after Mn administration. These maps showed excellent quantitative agreement with PET and AR images of the same animal, confirming that MR R1 change accurately measures Mn concentration in rat brain in the range 0 to 0.1 mM, in the absence of other sources of R1 change. However, at some point above this concentration, measured R1 becomes inaccurate. Accordingly, Mn concentration mapping with MRI is a potentially useful tool to improve the experimental power of Mn-uptake imaging to assess neuronal activation.