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Dams are considered one of the most important threats to freshwater ecosystems. To date, assessments of the impact of riverine impoundments are based primarily on taxonomic approaches where little can be inferred about functional ecological change. We assessed the impact of damming in a cold region river fish community in Alberta, Canada, by integrating taxonomic and trait-based approaches over time (before, during the first 5 years, and after 5 years of dam construction), considering the longitudinal habitat and environmental change created by reservoir formation (downstream, reservoir, and upstream). Integrating both approaches was found to be informative, as alterations to taxonomic composition in fish communities provided initial clues to a functional response in a spatiotemporal context. Biomonitoring should therefore explicitly consider longitudinal spatial gradients in the design, implementation, and evaluation of management actions. Understanding the underlying environmental causes of why the combination of some traits are connected to the risk of species loss or a decline in their distribution is an important step towards the development of better conservation and mitigation strategies. Les barrages sont consideres comme constituant l'une des plus grandes menaces pour les ecosystemes d'eau douce. A ce jour, les evaluations de l'impact des ouvrages de retenue dans les rivieres reposent principalement sur des approches taxonomiques qui en disent peu sur les changements ecologiques fonctionnels. Nous avons evalue l'impact de la construction de barrages dans une communaute de poissons de riviere de region froide en Alberta (Canada) en integrant des approches taxonomiques et basees sur les caracteres dans le temps (avant la construction du barrage, durant les 5 premieres annees et 5 ans apres la construction), en tenant compte des modifications longitudinales des conditions ambiantes et des habitats decoulant de la formation du reservoir (aval, reservoir et amont). L'integration des deux approches s'est averee instructive puisque les modifications de la composition taxonomique des communautes de poissons fournissent des indices initiaux d'une reaction fonctionnelle dans un contexte spatiotemporel. La biosurveillance devrait donc tenir compte explicitement des gradients spatiaux longitudinaux dans la conception, la mise en reuvre et revaluation de mesures d'amenagement. La comprehension des causes environnementales du lien entre la combinaison de certains caracteres et le risque de perte d'especes ou de diminution d'aires de repartition est une etape importante vers l'elaboration de meilleures strategies de conservation et d'attenuation. [Traduit par la Redaction], Introduction Historically, dams, and the reservoirs they create, have been viewed as a benefit to society (Baxter 1977; Nilsson et al. 2005). However, in the last decade, a wide range [...]

In the past decade, a large volume of peer‐reviewed papers has examined the potential impacts of oil and gas resource extraction in the Canadian oil sands (OS). A large proportion focuses on terrestrial biology: wildlife, birds, and vegetation. We provide a qualitative synthesis of the condition of the environment in the oil sands region (OSR) from 2009 to 2020 to identify gaps and progress cumulative effects assessments. Our objectives were to (1) qualitatively synthesize and critically review knowledge from the OSR; (2) identify consistent trends and generalizable conclusions; and (3) pinpoint gaps in need of greater monitoring or research effort. We visualize knowledge and terrestrial monitoring foci by allocating papers to a conceptual model for the OS. Despite a recent increase in publications, focus has remained concentrated on a few key stressors, especially landscape disturbance, and a few taxa of interest. Stressor and response monitoring is well represented, but direct monitoring of pathways (linkages between stressors and responses) is limited. Important knowledge gaps include understanding effects at multiple spatial scales, mammal health effects monitoring, focused monitoring of local resources important to Indigenous communities, and geospatial coverage and availability, including higher attribute resolution in human footprint, comprehensive land cover mapping, and up‐to‐date LiDAR coverage. Causal attribution based on spatial proximity to operations or spatial orientation of monitoring in the region is common but may be limited in the strength of inference that it provides. Integr Environ Assess Manag 2022;18:388–406. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). KEY POINTS: We provide a qualitative synthesis of the condition of the environment in the Canadian oil sands region (OSR) in northeastern Alberta from 2009 to 2020 to identify gaps and progress cumulative effects assessments. Despite a recent increase in publications, focus has remained concentrated on a few key stressors and a few taxa of interest, for which monitoring is well represented, though direct monitoring of pathways (linkages between stressors and responses) is limited. Important gaps include a lack of understanding of effects at multiple spatial scales, a lack of focused monitoring of local resources important to Indigenous communities, and geospatial data resolution and availability. Causal attribution based on spatial proximity to oil sands operations or spatial orientation of monitoring in the OSR is common but may be limited in the strength of inference that it provides. [ABSTRACT FROM AUTHOR]

The desire to document and understand the cumulative implications of oil sands (OS) development in the ambient environment of northeastern Alberta has motivated increased investment and release of information in the past decade. Here, we summarize the knowledge presented in the theme‐based review papers in this special series, including air, surface water, terrestrial biology, and Indigenous community‐based monitoring in order to (1) consolidate knowledge gained to date, (2) highlight key commonalities and gaps, and (3) leverage this knowledge to assess the state of integration in environmental monitoring efforts in the OS region and suggest next steps. Among air, water, and land studies, the individual reviews identified a clear focus on describing stressors, including primarily (1) contaminant emission, transport, transformation, deposition, and exposure, and (2) landscape disturbance. These emphases are generally partitioned by theme; air and water studies focus heavily on chemical stressors, whereas terrestrial monitoring focuses on biological change and landscape disturbance. Causal attribution is often stated as a high priority objective across all themes. However, studies often rely on spatial proximity to attribute cause to industrial activity, leaving causal attribution potentially confounded by spatial covariance of both OS‐ and non‐OS‐related stressors in the region, and by the complexity of interacting pathways between sources of environmental change and ecological receptors. Geospatial and modeling approaches are common across themes and may represent clear integration opportunities, particularly to help inform investigation‐of‐cause, but are not a replacement for robust field monitoring designs. Cumulative effects assessment remains a common focus of regional monitoring, but is limited in the peer‐reviewed literature, potentially reflecting a lack of integration among monitoring efforts beyond narrow integrated interpretations of results. Addressing this requires greater emphasis on a priori integrated data collection and integrated analyses focused on the main residual exposure pathways, such as atmospheric deposition. Integr Environ Assess Manag 2022;18:428–441. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). KEY POINTS: Our summary of the peer‐reviewed literature since 2010 from the Alberta oil sands region reveals an emphasis on chemical stressors and their association with atmospheric emissions, transport, transformation, and deposition, as well as an emphasis on landscape disturbance and associated effects.System‐wide gaps in the literature, including topics of concern to local Indigenous communities, derive from a disconnect between theme areas (air, water, land), contribute to an incomplete knowledge of functional linkages, and may undermine the ability to inform regulatory or policy action.Combining papers not explicitly designed together creates interpretative and analytical challenges, and overcoming these may require future optimization of and integration between targeted monitoring projects and entire theme areas. [ABSTRACT FROM AUTHOR]

This review is part of a series synthesizing peer‐reviewed literature from the past decade on environmental monitoring in the oil sands region (OSR) of northeastern Alberta. It focuses on atmospheric emissions, air quality, and deposition in and downwind of the OSR. Most published monitoring and research activities were concentrated in the surface‐mineable region in the Athabasca OSR. Substantial progress has been made in understanding oil sands (OS)‐related emission sources using multiple approaches: airborne measurements, satellite measurements, source emission testing, deterministic modeling, and source apportionment modeling. These approaches generally yield consistent results, indicating OS‐related sources are regional contributors to nearly all air pollutants. Most pollutants exhibit enhanced air concentrations within ~20 km of surface‐mining activities, with some enhanced >100 km downwind. Some pollutants (e.g., sulfur dioxide, nitrogen oxides) undergo transformations as they are transported through the atmosphere. Deposition rates of OS‐related substances primarily emitted as fugitive dust are enhanced within ~30 km of surface‐mining activities, whereas gaseous and fine particulate emissions have a more diffuse deposition enhancement pattern extending hundreds of kilometers downwind. In general, air quality guidelines are not exceeded, although these single‐pollutant thresholds are not comprehensive indicators of air quality. Odor events have occurred in communities near OS industrial activities, although it can be difficult to attribute events to specific pollutants or sources. Nitrogen, sulfur, polycyclic aromatic compounds (PACs), and base cations from OS sources occur in the environment, but explicit and deleterious responses of organisms to these pollutants are not as apparent across all study environments; details of biological monitoring are discussed further in other papers in this special series. However, modeling of critical load exceedances suggests that, at continued emission levels, ecological change may occur in future. Knowledge gaps and recommendations for future work to address these gaps are also presented. Integr Environ Assess Manag 2022;18:333–360. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). KEY POINTS: Air emissions from oil sands activities are regional contributors to nearly all air pollutants, with most exhibiting enhanced concentrations within ~20 km of surface‐mining activities, and some enhanced at greater distances (>100 km) downwind.Temporal trends identified in ambient air‐monitoring data vary with the statistical analysis applied; existing ambient air quality guidelines and standards are rarely exceeded; however, single‐pollutant thresholds are not comprehensive indicators of air quality.Co‐located deposition‐ and ecological‐effects monitoring identify a link between nitrogen deposition and ecological changes in jack pine, bog, and poor fen ecosystems—there is limited evidence of acidification to date, but predictive modeling indicates areas exceeding critical loads of acidification.Knowledge gaps are synthesized and recommendations for future work to address these gaps are presented. [ABSTRACT FROM AUTHOR]

Damming is one of the main causes of the global decline in freshwater biodiversity. Yet, many hydroelectric dams are being built (or planned) in the Neotropics, where the high species diversity and lack of basic ecological knowledge provide a major obstacle to understanding the effects of this environmental change, which has been mostly described from the perspective of taxonomic change. However, this approach does not account for biological function. Trait-based analysis provides an alternative approach to bioassessment. We assessed the impact of dam closure on the functional structure of fish communities of a Neotropical river by applying trait-based analyses to the response of individual traits aggregated at the assemblage level. Fish data were collected during three distinct time periods (1 year before, 1 year after and 5 years after dam closure), at eight sites located downstream of the dam, in the reservoir, transition zone and upstream. The results indicated that reproduction strategies (migration and parental care) and diet (detritivores) were the trait categories mostly affected by the dam, with the response of downstream assemblages differing from upstream of the dam. A trait-based analysis to the impact of damming on fish communities appears to be a promising approach using an initial descriptive analysis of individual traits and regression models of multiple traits that reflect species' adaptation to the new environment. This study provides both an alternative and complementary approach to taxonomic assessment of impacts from damming, contributing towards a more robust evaluation of the response of fish communities to dams. [ABSTRACT FROM AUTHOR]

The study of phylogeographical patterns may contribute to a better understanding of factors affecting the dispersal of organisms in ecological and historical times. For intertidal organisms, islands are particularly suitable models allowing the test of predictions related to the efficacy of pelagic larvae dispersal. Here, we study the phylogeographical patterns and gene flow within three groups of species of the genus Patella present in the Macaronesian Islands that have been previously shown to be monophyletic. The genetic variability of around 600 bp of the mitochondrial gene cytochrome c oxidase subunit I was studied by single strand conformation polymorphism and/or sequencing for seven species of limpets. A total of 420 samples were analysed from the Macaronesian archipelagos, North Africa, and Atlantic and Mediterranean shores of the Iberian Peninsula. No clear geographical pattern or temporal congruence was found between the three groups of species, pointing to independent histories and colonization events. However, for the three groups, the split between the Macaronesian and the mainland forms most probably occurred before 3.9 million years ago, predating the establishment of the current circulation patterns. The presence of pelagic larvae in these species is shown to be insufficient to ensure gene flow between continental and Macaronesian populations and between the Macaronesian archipelagos. In the endangered Azorean populations of Patella candei, there is restricted gene flow to Flores and Graciosa. [ABSTRACT FROM AUTHOR]