World Congress on Risk 2015
19-23 July, 2015, Singapore

Online Program

Session Schedule & Abstracts

* Disclaimer: All presentations represent the views of the authors, and not the organizations that support their research. Please apply the standard disclaimer that any opinions, findings, and conclusions or recommendations in abstracts, posters, and presentations at the meeting are those of the authors and do not necessarily reflect the views of any other organization or agency. Meeting attendees and authors should be aware that this disclaimer is intended to apply to all abstracts contained in this document. Authors who wish to emphasize this disclaimer should do so in their presentation or poster. In an effort to make the abstracts as concise as possible and easy for meeting participants to read, the abstracts have been formatted such that they exclude references to papers, affiliations, and/or funding sources. Authors who wish to provide attendees with this information should do so in their presentation or poster.

Common abbreviations

Tuesday 21-07-2015

Ecological Risk Assessment in Tropical Asia-Pacific and Other Regions of the Pacific Basin, Part I

Room: Breakthrough   13:30–15:00

Chair(s): Jenny Stauber

1    What’s Unique about Ecological Risk Assessment in Tropical Asia-Pacific? Stauber J    (256)

Abstract: Tropical regions and the Pacific Basin have unique ecosystems comprising sensitive habitats, unusual taxa and a unique biodiversity compared to temperate regions. The Wallace Line differentiates the Asian ecozone from the mixture of Asian and Australian found further southeast. Direct application of ecological risk assessment (ERA) techniques and tools developed for North America and Europe to tropical regions may not be appropriate due to differences in geochemistry, organic matter, climatic conditions and differences in the physiology of the evolutionarily distinctive biota. These differences may be particularly important for metals, for which bioavailability models have been developed in temperate regions to support refined risk assessment. Bioavailability-based risk assessment of metals relies on accurate knowledge of metal speciation and the ability to predict effects to wide ranges of taxa, both of which are poorly studied in the tropical Asia-Pacific region. Specific tropical habitats at risk include marine and estuarine mangroves, coral reefs, seagrass communities, and pelagic and benthic marine ecosystems. One approach is to adapt the risk assessment tools and modelling approaches based on data from temperate regions, usually North America and Europe, and validated to specific geochemical regions and relationships. These models may or may not be applicable to tropical ecosystems. Both the exposure data such as temperature, water hardness, pH and dissolved organic carbon, as well as effects data for contaminants generated from laboratory tests with temperate species, have often simply been extrapolated to tropical regions to determine risk. This paper will set the scene for the tropical ecological risk assessment session using a number of examples of risk assessment tools examining exposure and effects data to assess the risk of metals in tropical aquatic environments.

2    The use of the Bayes net relative risk model as a central part of an adaptive management program. Landis WG, Western Washington University; Ayre KK, Western Washington University; Harris MJ, Western Washington University; Herring C, Western Washington University; Stinson J, Western Washington University (189)

Abstract: In the mid-1990s the initial relative risk model for regional risk assessment was developed and since then we and other researchers have applied it to numerous risk assessments. Innately the relative risk model incorporates multiple sources of multiple stressors and the characteristics of the landscape to calculate risk to multiple endpoints. The application of Bayesian networks (Bayes nets) to the fundamental structure of the relative risk model, now the BN-RRM, has added a number of new abilities to the process. Not only can risk due to current conditions be examined but also changes due to remediation efforts or alterations in landscape use can be evaluated. Since the BN-RRM intrinsically performs a sensitivity analysis to identify and evaluate the variables most critical in determining the risk. The distribution of risk in the landscape and the uncertainty and sensitivity analyses inform both the design of laboratory experiments and the planning of long-term field monitoring programs. The result is a series of predictions that are testable both about current conditions and the efficacy of proposed management alternatives. Recent research demonstrates that it is now possible to integrate human health and well being pathways to the ecological risk assessment. Because of the ability of Bayes net to back calculate from a desired state to estimate the necessary initial conditions the trade-offs of different management options can be examined to all three types of endpoints (ecological, well-being and human health). As demonstrated for forestry management by Nyberg et al, the incorporation of the Bayesian network allows the BN-RRM to be the central analysis segment of an adaptive management process. Finally, The presentation will outline the use of the BN-RRM as a critical part of the adaptive management process for current sites and demonstrate sustainable environmental management for tropical sites.

3    Risk assessment approaches used for tropical wetlands in northern Australia. van Dam R, Environmental Research Institute of the Supervising Scientist, Darwin, Australia; Bartolo R, Environmental Research Institute of the Supervising Scientist, Darwin, Australia; Bayliss P, CSIRO Oceans & Atmosphere Flagship Program, Brisbane, Australia; Finlayson M, Institute for Land, Water and Society, Charles Sturt University, Albury, Australia (331)

Abstract: Various ecological risk assessment approaches have been used since the 1990s to quantify and compare the risks of the pressures to the wetlands of tropical northern Australia, including invasive species, mining, primary production (e.g. irrigated agriculture, cattle grazing), poor fire management, and climate change/sea level rise. These approaches have encompassed different temporal and spatial scales, and used various risk analysis methods. This presentation focuses on a number of risk assessments that illustrate the breadth and depth of work undertaken. Risks of a herbicide and its target weed to wetlands: Probablistic effects characterization and temporal exposure modeling were used to quantify risk to aquatic life of a herbicide applied to a wetland weed, whilst spatial and habitat suitability modeling were used to quantify the risk of the weed infesting wetland habitats across northern Australia. Relative risks of pressures to aquatic ecosystems of northern Australia: A spatially-explicit relative risk model was applied across a 1.1 million km2 area of northern Australia. It enabled identification of the threats with the highest risk, and the regions/ecosystems at most risk from these, and represented a powerful prioritization tool for more detailed quantitative risk analyses. Relative risks of point source, mining-related contaminants and diffuse landscape scale threats to a wetland: Bayesian approaches were used to quantify, integrate and compare ecological risks to a World Heritage- and Ramsar-listed wetland from feral pigs, aquatic weeds, unmanaged fire, saltwater intrusion and contaminants in mine surface water discharges. Refining risk analysis of a mining-related contaminant: Continuous water quality monitoring enabled detailed temporal characterisation of mine water discharges into a high conservation/ecological value stream. This informed a comprehensive pulse exposure effects assessment for the key contaminant, magnesium, from which a model was developed for prediction of risks based on magnesium pulse magnitude and duration.

4    Ecological Risk Assessment in Tropical Asia-Pacific and Other Regions of the Pacific Basin. Pollino C., CSIRO Land and Water (202)

Abstract: Cumulative Risk Assessment aims to analyse, characterize and quantify the combined threats of multiple stressors on a receiving environment. In this presentation, we will overview the steps being undertaken and in progress for a risk assessment, aimed at looking at the risks to the local and landscape terrestrial and aquatic environments post the closure of a mining operation in Northern Australia. The presentation will focus on three steps: 1. Framing the cumulative risk assessment using causal conceptual models; 2. Implementing a screening exercise to focus the quantitative risk assessment; 3. Developing a probabilistic network model to assess cumulative risks. Using a participatory multi-disciplinary process, causal conceptual models were used to define the relationship between stressors and outcomes, with associated sources, transport pathways and measurement and assessment endpoints. This resulted in nine causal conceptual models, which focused on aquatic, terrestrial and human systems, and their interactions. Approximately 100 potential stressors were identified from this exercise. To focus the quantitative assessment on those which are relevant and are likely to occur within the assessment temporal and spatial scales, a screening exercise was undertaken. This used a survey and participatory workshop process to review each potential stressor and their interaction with endpoints, and to exclude stressors of a very low likelihood. The confidence in participants evaluation of each stressor-endpoint was assessed to capture uncertainty and prevent stressors from being screened out where knowledge was poor. Based on the first two assessment steps, a probabilistic (Bayesian) network is being developed to quantitatively assess cumulative risks, considering variability, uncertainty and interactions across scales. The outcomes will be used to evaluate risks and the likelihood of success of risk management actions, across spatial and temporal scal

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