Susan J Nichols

Susan J Nichols
University of Canberra ·  Institute for Applied Ecology (IAE)

Doctor of Philosophy

About

67
Publications
14,804
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1,047
Citations
Citations since 2016
36 Research Items
669 Citations
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Introduction
My particular interest is freshwater science and biological assessment of river condition. A fundamental interest in aquatic invertebrate ecology underpins my research on river condition assessment. The Australian River Assessment System (AUSRIVAS) is a specific interest. Another interest is the adaption of causal criteria (as used in epidemiology) and making better use of published research for use in environmental assessment.

Publications

Publications (67)
Article
Full-text available
Freshwater biota are more comprehensive and direct indicators of biological impacts, and more meaningful to the public than water quality or physical habitat surrogates. Freshwater biotic data and the multiple biological indicators developed from them offer a much richer array of data for assessing the impacts of pollution controls than a limited s...
Article
Full-text available
Understanding the cumulative effects of multiple stressors on biodiversity is key to managing their impacts. Stressor interactions are often studied using an additive/antagonistic/synergistic typology, aimed at identifying situations where individual stressor effects are reduced or amplified when they act in combination. Here, we analysed variation...
Article
Full-text available
Rivers suffer from multiple stressors acting simultaneously on their biota, but the consequences are poorly quantified at the global scale. We evaluated the biological condition of rivers globally, including the largest proportion of countries from the Global South published to date. We gathered macroinvertebrate‐ and fish‐based assessments from 72...
Article
The most parsimonious interpretation of our experimental findings (Bray 2019; Kefford 2022) is that the effect of experimental increases in salinity on stream macroinvertebrate communities, was altered by organisms from a high-salinity site. This interpretation is consistent with long-established and widely accepted ecological and ecotoxicological...
Article
Full-text available
The application of road de-icing salts has the potential to salinize fresh waters and degrade habitat for aquatic organisms. In the Australian Alps, the ecological effects of even small salinity increases from de-icing may be different than in North America and Europe because of (1) differences in the evolutionary history, and (2) areas with de-ici...
Article
Full-text available
Freshwater biota are at risk globally from increasing salinity, including increases from deicing salts in cold regions. A variety of metrics of toxicity are used when estimating the toxicity of substances and comparing the toxicity between substances. However, the implications of using different metrics are not widely appreciated. Using the mayfly...
Preprint
Biodiversity is declining, typically because of multiple anthropogenic stressors. Cumulative effects of multiple stressors are classified as additive, when cumulative effects are as expected from the stressor’s singular effects, synergistic when greater than additive or antagonistic when less than additive. Less attention has been given to the cons...
Article
Salinity is increasing in many naturally fresh waters because of human activities, and there are concerns about the ecological effects of these increases. Salinity, as with any stressor, can affect organisms both directly and indirectly. In a previous study (Bray et al. 2019), we evaluated the relative importance of direct and indirect effects of i...
Article
Full-text available
The authors note that there may not have been sufficient information provided in two sections of the paper (Brooks et al., 2021), and regret that there was an error in a calculation of one response ratio. None of these issues alter the results or any conclusions of the paper, nevertheless for transparency we explain these matters here. The followin...
Article
Full-text available
Human‐mediated salinity increases are occurring in freshwaters globally, with consequent negative effects on freshwater biodiversity. Salinity comprises multiple anions and cations. While total concentrations are typically used to infer effects, individual ion concentrations and ion ratios are critical in determining effects. Moreover, estimates of...
Article
Environmental degradation of rivers in agricultural landscapes is typically caused by multiple co-occurring stressors, but how interactions among stressors affect freshwater ecosystems is poorly understood. Therefore, we investigated the sensitivity and specificity of several measures of benthic macroinvertebrate community response to the individua...
Article
Within human modified ecosystems the effects of individual stressors are difficult to establish amid co-occurring biological processes, environmental gradients and other stressors. Coupled examination of several endpoints across different levels of organisation may help elucidate the individual and combined effects of stressors and interactions. Ma...
Article
Full-text available
The biological assessment of rivers i.e., their assessment through use of aquatic assemblages, integrates the effects of multiple-stressors on these systems over time and is essential to evaluate ecosystem condition and establish recovery measures. It has been undertaken in many countries since the 1990s, but not globally. And where national or mul...
Article
Full-text available
Salinity is increasing in many naturally fresh waters because of human activities, and there are concerns about the ecological effects of these increases. Salinity, as with any stressor, can affect organisms both directly and indirectly. In a previous study (Bray et al. 2019), we evaluated the relative importance of direct and indirect effects of i...
Article
Pesticides are increasingly recognised as a threat to freshwater biodiversity, but their specific ecological effects remain difficult to distinguish from those of co-occurring stressors and environmental gradients. Using mesocosms we examined the effects of an organophosphate insecticide (malathion) on stream macroinvertebrate communities concurren...
Article
Full-text available
Macroinvertebrates are commonly sampled for bioassessment of freshwater ecosystems. However, current bioassessment protocols involve laborious sorting of the animals from the debris (sample matrix) and morphological identification, where species level identifications are often difficult. DNA metabarcoding has the potential to improve bioassessment...
Article
Full-text available
1. Pesticide concentrations are correlated with regional declines in stream invertebrate diversity. Experimental studies have identified that pesticides can have strong and persistent negative effects on aquatic ecosystems. These effects may occur at concentrations orders of magnitude lower than laboratory toxicity studies predict. Synergism among...
Article
Ecological effects of mining activity are a global concern; with most studies ascribing the effect on freshwater biota to metal toxicity from metal uptake through dietary or dissolved metal exposure. Although the potential for smothering effects from metal flocs has been suggested, studies have not separated metal toxicity effects and smothering ef...
Presentation
Full-text available
To support sound decision-making in environmental management, we need rigorous, defensible, and transparent synthesis of scientific evidence. The Association for the Sciences of Limnology and Oceanography (ASLO) and associated aquatic science societies are leaders in applying science to decision-making, and yet many environmental decisions are stil...
Article
Full-text available
Toxicants have both sub-lethal and lethal effects on aquatic biota, influencing organism fitness and community composition. However, toxicant effects within ecosystems may be altered by interactions with abiotic and biotic ecosystem components, including biological interactions. Collectively, this generates the potential for toxicant sensitivity to...
Article
To support sound decision-making in environmental management, we need rigorous, defensible, and transparent synthesis of scientific evidence. The Association for the Sciences of Limnology and Oceanography and associated aquatic science societies are leaders in applying science to decision-making , and yet many environmental decisions are still at r...
Article
Adaptive management is an experimental approach used by water management agencies around the world to manage and restore aquatic ecosystems. The effectiveness of the approach can often be constrained by inflexible institutional arrangements. In this paper we compare two cases where agencies have implemented adaptive management to manage and restore...
Article
Implementing policies to return water to the environment is challenging. We developed an approach to integrate ecological responses with river management models to provide a link between flow and ecology. This paper aims to summarize the findings of a multifaceted project bringing together multiple lines of evidence to achieve a proof-of-concept ap...
Article
Full-text available
Rivers provide many social and environmental services that benefit humanity. A critical role of water mangers is to prioritize water allocation options that trade off socioeconomic and hydro-ecological benefits in rivers. Methods for multi-criteria decision analysis (MCDA) provide a structured and systematic manner for researchers to aid in this pr...
Article
Macroinvertebrates are widely used for monitoring freshwater ecosystems. In most monitoring programs, identifications take substantial time and expense. Methods that improve the speed, accuracy and cost-effectiveness of macroinvertebrate identification would benefit such programs. Increasingly, DNA barcodes are being used to provide accurate specie...
Article
Accurate and informative methods for evidence synthesis that are also simple and inexpensive to implement would greatly increase our ability to use scientific research results to better manage natural environments. Across the world, pressure to use evidence-based environmental management is increasing, but little guidance exists as to what 'evidenc...
Article
Investigators attempting to demonstrate causal relationships in environmental systems face challenges associated with natural variability, multiple stressors, the difficulty of performing rigorous experiments, and the time and money required to undertake such studies. Rapid, transparent, and logical methods are needed to synthesize and evaluate evi...
Article
Full-text available
Declining water quality and ecological condition is a typical trend for rivers and streams worldwide as human demands for water resources increase. Managing these natural resources sustainably is a key responsibility of governments. Effective water management policies require information derived from long-term monitoring and evaluation. Biological...
Article
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Aquatic ecosystems are under threat from multiple stressors, which vary in distribution and intensity across temporal and spatial scales. Monitoring and assessment of these ecosystems have historically focussed on collection of physical and chemical information and increasingly include associated observations on biological condition. However, ecosy...
Article
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Confidence in any bioassessment method is related to its ability to detect ecological improvement or impairment.We evaluated Australian River Assessment (AUSRIVAS)-style predictive models built using reference site data sets from the Australian Capital Territory (ACT), the Yukon Territory (YT; Canada), and the Laurentian Great Lakes (GL; North Amer...
Article
We describe software to facilitate systematic reviews in environmental science. Eco Evidence allows reviewers to draw strong conclusions from a collection of individually-weak studies. It consists of two components. An online database stores and shares the atomized findings of previously-published research. A desktop analysis tool synthesizes this...
Conference Paper
Full-text available
Key Points • Community based monitoring of water quality and aquatic ecosystems such as Waterwatch in Australia comprise an important portion of worldwide community monitoring efforts. • Waterwatch data have traditionally been criticised as being of inferior quality compared with professionally collected data yet there are few published comparisons...
Article
River managers in Australia are managing in the face of extremes to provide security of water supply for people, production and the environment. Balancing the water requirements of people, environments and economies requires that water security is viewed holistically, not just in terms of the water available for human consumption. Common definition...
Article
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Effectively transferring complex scientific ideas into the policy domain is a serious challenge, but an essential one given the important role of science in assessing the implications of a changing climate and resulting water shortages in Australia. Eco Evidence, a method for conducting systematic reviews of the scientific literature using causal c...
Article
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The environment is being increasingly recognized as a legitimate user of water. However, tension between environmental and consumptive uses remains and environmental water allocations may be subject to legal challenge. Current predictions of ecological response to altered flow regimes are not sufficiently transparent or robust to withstand such cha...
Article
Summary1. In rivers affected by drought, flow regulation can further reduce flow and intensify its effects. We measured ecological responses to environmental flows, during a prolonged drought in a regulated river (Cotter River), compared with a drought affected, unregulated river (Goodradigbee River) in south‐eastern Australia.2. Environmental flow...
Article
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Sound decision making in environmental research and management requires an understanding of causal relationships between stressors and ecological responses. However, demonstrating cause–effect relationships in natural systems is challenging because of difficulties with natural variability, performing experiments, lack of replication, and the presen...
Chapter
Environmental flows were implemented in the Cotter River in 1999 as a requirement of the Australian Capital Territory (ACT) Water Resources Act. A multi-disciplinary group composed of representatives from a water utility, ACT government, and research organisations was formed to manage the Cotter River environmental flows program, aiming to achieve...
Technical Report
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This manual describes the Eco Evidence analysis method, which is used to evaluate evidence from environmental science studies in a standardized, transparent and objective manner, which reduces bias and subjectivity. The analysis method draws together information from the studies to assess how a particular human activity or natural event may influen...
Article
Climate change is gradual and long-term, consistently collected data are required to detect resulting biological responses and to separate such responses from local effects of human activities that monitoring programs usually are designed to assess. The reference-condition approach is commonly used in freshwater assessments that use predictive mode...
Article
Full-text available
We analyzed long-term changes in macroinvertebrate communities in a Mediterranean temporary stream in southern Portugal over 15 y (1993-2008) at 10 locations with 3 degrees of physicochemical disturbance (reference, high disturbance, and mild disturbance). We related year-to-year variation of macroinvertebrate communities to long-term (59 y) inform...
Article
The European Water Framework Directive (WFD 2000) brought the need in European Union countries to establish consistent quantitative methods for the water quality assessment of streams, using aquatic communities. With this work we aimed to develop predictive models using macroinvertebrate communities that could be used in Portugal as an alternative...
Article
The rapid bioassessment technique we investigate (AUSRIVAS) requires a nationally standardized sampling protocol that uses a single collection of macroinvertebrates (without replication) taken from 10m of specific habitats (e.g. stream edge and/or riffle) and sub-samples of 200 animals. The macroinvertebrate data are run through predictive models t...
Article
Aquatic macroinvertebrates are commonly used biological indicators for assessing the health of freshwater ecosystems. However, counting all the invertebrates in the large samples that are usually collected for rapid site assessment is time-consuming and costly. Therefore, sub-sampling is often done with fixed time or fixed count live-sorting in the...
Article
Full-text available
This study examines the ecological effects of serial impoundments (three dams) on a rocky upland stream in southeastern Australia. Physical, chemical and biological changes were quantified and interpreted within a three-level hierarchy of effects model developed previously by Petts [1984, Impounded Rivers. John Wiley and Sons, New York] and the Aus...
Article
Full-text available
South-east Queensland (Australia) streams were described by 21 local habitat variables that were chosen because of their potential association with fish distribution. An Assessment by a Nearest Neighbour Analysis (ANNA) model used large-scale variables that are robust to human influence to predict what the values of each of the 21 local habitat var...
Article
The pervasive modification of river systems by humans has created a need for assessment methods that determine site-specific reference communities across such landscapes. Where the composition of taxa under undisturbed conditions (reference condition communities) can be determined for a site, the site may then be assessed by comparing the observed...
Article
Every year, millions of dollars are spent on river management and rehabilitation activities across Australia. Most of these activities are based on assumptions about the ecology of river systems and potential causes of degradation. River management activities are widespread but assessment of the their effectiveness relative to anticipated ecologica...
Conference Paper
Every year, millions of dollars are spent on river management and rehabilitation activities across Australia. Most of these activities are based on assumptions about the ecology of river systems and potential threats or causes of degradation. While river management activities are widespread, monitoring and evaluation to assess if . interventions ha...
Article
Full-text available
A framework to Set Ecological Targets (SET) was developed as a tool for stakeholder groups involved in setting environmental targets. The framework was designed to incorporate current scientific information and reach agreement about trade-offs between environmental, social, and economic requirements of river systems to achieve ecological outcomes....