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1.
J Environ Manage ; 344: 118625, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37467519

RESUMEN

Ecosystem responses to increasing human pressures are complex and diverse, affecting organisms across all trophic levels. This has prompted the development of methods that integrate information across many indicators for environmental management. Legislative frameworks such as the European Water Framework Directive (WFD), specifically prescribe that integrated assessme nt (IA) of ecological status must consider indicators representing various biological and supporting quality elements. We present a general approach for an IA system based on a piece-wise linear transformation of indicator distributions to a standardized scale, allowing for integrating information from multiple and diverse indicators through a policy-dependent aggregation scheme. Uncertainties associated with monitoring data used for calculating indicators and their propagation throughout the integration scheme allow for confidence assessment at all levels of the hierarchical integration. Specific pressures leading to ecological impact can be identified through the most impaired indicators in the hierarchical and transparent aggregation scheme. The IA and its confidence are facilitated though the development of an online tool that accesses information from monitoring databases and presents the outcome at all levels of the assessment, ensuring consistency and transparency in the calculations for all potential stakeholders. We demonstrate the versality and applicability of the approach using indicators and aggregation principles from the Swedish national guidelines for assessing ecological status of rivers, lakes and coastal waters according to the WFD. Although the approach and the tool were developed specifically for the WFD ecological status assessment in Sweden, the generality of the approach implies that it can easily be adapted to the WFD assessment methods of other countries as well as other policies, where an integrated assessment is required.


Asunto(s)
Ecosistema , Contaminantes Químicos del Agua , Humanos , Monitoreo del Ambiente , Contaminación del Agua , Contaminantes Químicos del Agua/análisis , Agua , Ríos
2.
J Lesbian Stud ; 27(1): 107-126, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35938751

RESUMEN

This case study centers on the narrative accounts of a lesbian couple in a binational relationship (i.e., two women from different countries) who left the United States (U.S.) at a time when immigration laws did not recognize their union. Given that they could not legally stay in the U.S. together, they immigrated to the Netherlands and subsequently to Canada. When DOMA was overturned and the couple was eligible to apply for immigration to the U.S., they opted to remain in Canada, in part due to the strain of multiple migrations. This concept has been described as the complex process that accompanies more than one immigration experience and the cumulative effect that this can have on couples and families over time, particularly when multiple resettlements have taken place. A descriptive case study methodology was employed to investigate the perceptions of multiple migrations of this lesbian binational couple, focusing mainly on their experiences in Canada. Specifically, individual interviews were conducted with each woman to explore their lived experiences of multiple migration and the impact this has had on various aspects of their lives, including those occurring at the intersection of privilege and oppression. A description of each woman is presented, followed by the significant themes that emerged from this study, including immigration difficulties and the centrality of relationship. Implications for psychological training, practice, research, policy were presented.


Asunto(s)
Homosexualidad Femenina , Minorías Sexuales y de Género , Humanos , Femenino , Estados Unidos , Amor , Emigración e Inmigración , Canadá
3.
Conserv Biol ; 36(3): e13856, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34729816

RESUMEN

Conserving coral reefs is critical for maintaining marine biodiversity, protecting coastlines, and supporting livelihoods in many coastal communities. Climate change threatens coral reefs globally, but researchers have identified a portfolio of coral reefs (bioclimatic units [BCUs]) that are relatively less exposed to climate impacts and strongly connected to other coral reef systems. These reefs provide a proactive opportunity to secure a long-term future for coral reefs under climate change. To help guide local management efforts, we quantified marine cumulative human impact (CHI) from climate, marine, and land pressures (2013 and from 2008 to 2013) in BCUs and across countries tasked with BCU management. Additionally, we created a management index based on common management measures and policies for each pressure source (climate, marine, and land) to identify a country's intent and commitment to effectively manage these pressures. Twenty-two countries (79%) had increases in CHI from 2008 to 2013. Climate change pressures had the highest proportional contribution to CHI across all reefs and in all but one country (Singapore), but 18 BCUs (35%) and nine countries containing BCUs (32%) had relatively high land and marine impacts. There was a significant positive relationship between climate impact and the climate management index across countries (R2 = 0.43, p = 0.02), potentially signifying that countries with greater climate impacts are more committed to managing them. However, this trend was driven by climate management intent in Fiji and Bangladesh. Our results can be used to guide future fine-scale analyses, national policies, and local management decisions, and our management indices reveal areas where management components can be improved. Cost-effectively managing local pressures (e.g., fishing and nutrients) in BCUs is essential for building a climate-ready future that benefits coral reefs and people.


Identificación de Oportunidades de Gestión para Combatir las Amenazas Climáticas, Marinas y Terrestres en los Arrecifes de Coral Menos Expuestos al Clima Resumen La conservación de los arrecifes de coral es de suma importancia para mantener la biodiversidad marina y para sostener el medio de vida en muchas comunidades costeras. El cambio climático es una amenaza mundial para los arrecifes de coral; aun así, los investigadores han identificado un portafolio de arrecifes de coral (unidades bioclimáticas[UBCs]) que se encuentran relativamente menos expuestos a los impactos climáticos y están conectados a otros sistemas arrecifales. Estos arrecifes proporcionan una oportunidad proactiva de asegurar un futuro a largo plazo para los arrecifes de coral frente al cambio climático. Para ayudar a guiar los esfuerzos locales de manejo, cuantificamos el impacto humano acumulativo (IHA) sobre los ambientes marinos a partir de las presiones climáticas, marinas y terrestres (del 2008 al 2013) en las UBCs y en los países encargados del manejo de estas. Además, creamos un índice de manejo con base en las medidas y políticas comunes de gestión para cada fuente de presión (clima, ambiente marino, suelo) para identificar la intención y el compromiso de cada país para manejar de manera efectiva estas presiones. Veintidós países (79%) tuvieron incrementos en el IHA entre 2008 y 2013. Las presiones por el cambio climático tuvieron la contribución proporcional más alta al IHA en todos los arrecifes y en todos los países excepto uno (Singapur), pero 18 UBCs (35%) y nueve países que cuentan con UBCs (32%) tuvieron impactos terrestres y marinos relativamente altos. Hubo una relación positiva significativa entre el impacto climático y el índice de manejo climático entre los países (R2 = 0.43, p = 0.02), lo que potencialmente significa que los países con un mayor impacto climático están más comprometidos con su manejo. Sin embargo, esta tendencia estuvo impulsada por las intenciones de manejo climático en Fiyi y en Bangladesh. Nuestros resultados pueden usarse para orientar los análisis a fina escala, las políticas nacionales y las decisiones locales de manejo en el futuro. Nuestros índices de manejo también revelan áreas en donde se pueden mejorar los componentes gestores. El manejo rentable de las presiones locales (p. ej.: la pesca, los nutrientes) dentro de las UBCs es esencial para construir un futuro preparado climáticamente que beneficie a los arrecifes y a las personas.


Asunto(s)
Antozoos , Arrecifes de Coral , Animales , Cambio Climático , Conservación de los Recursos Naturales , Ecosistema , Humanos
4.
Environ Health ; 21(1): 123, 2022 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-36471342

RESUMEN

BACKGROUND: In February 2021, over one hundred scientists and policy experts participated in a web-based Workshop to discuss the ways that divergent evaluations of evidence and scientific uncertainties are used to delay timely protection of human health and the environment from exposures to hazardous agents. The Workshop arose from a previous workshop organized by the European Environment Agency (EEA) in 2008 and which also drew on case studies from the EEA reports on 'Late Lessons from Early Warnings' (2001, 2013). These reports documented dozens of hazardous agents including many chemicals, for which risk reduction measures were delayed for decades after scientists and others had issued early and later warnings about the harm likely to be caused by those agents. RESULTS: Workshop participants used recent case studies including Perfluorooctanoic acid (PFOA), Extremely Low Frequency - Electrical Magnetic Fields (ELF-EMF fields), glyphosate, and Bisphenol A (BPA) to explore myriad reasons for divergent outcomes of evaluations, which has led to delayed and inadequate protection of the public's health. Strategies to overcome these barriers must, therefore, at a minimum include approaches that 1) Make better use of existing data and information, 2) Ensure timeliness, 3) Increase transparency, consistency and minimize bias in evidence evaluations, and 4) Minimize the influence of financial conflicts of interest. CONCLUSION: The recommendations should enhance the production of "actionable evidence," that is, reliable evaluations of the scientific evidence to support timely actions to protect health and environments from exposures to hazardous agents. The recommendations are applicable to policy and regulatory settings at the local, state, federal and international levels.


Asunto(s)
Informática Médica , Humanos , Incertidumbre , Educación , Internet
5.
J Environ Manage ; 308: 114634, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35151103

RESUMEN

Human activities in Antarctica were increasing before the COVID-19 pandemic, and tourism was not an exception. The growth and diversification of Antarctic tourism over the last few decades have been extensively studied. However, environmental impacts associated with this activity have received less attention despite an increasing body of scholarship examining environmental issues related to Antarctic tourism. Aside from raising important research questions, the potential negative effects of tourist visits in Antarctica are also an issue discussed by Antarctic Treaty Consultative Parties. This study presents the results of a meta-analysis of scholarly publications that synthesizes and updates our current knowledge of environmental impacts resulting from Antarctic tourism. A first publication database containing 233 records that focussed on this topic was compiled and subjected to a general bibliometric and content analysis. Further, an in-depth content analysis was performed on a subset of 75 records, which were focussed on showing specific research on Antarctic tourism impacts. The main topic, methods, management proposals, and research gaps highlighted by the respective authors of these 75 publications were assessed. The range of research topics addressed, the methods used - including the application of established research designs from the field of environmental impact assessment -, and the conclusions reached by the study authors are discussed. Interestingly, almost one third of the studies did not detect a direct relationship between tourism and significant negative effects on the environment. Cumulative impacts of tourism have received little attention, and long-term and comprehensive monitoring programs have been discussed only rarely, leading us to assume that such long-term programs are scarce. More importantly, connections between research and policy or management do not always exist. This analysis highlights the need for a comprehensive strategy to investigate and monitor the environmental impacts of tourism in Antarctica. A first specific research and monitoring programme to stimulate a debate among members of the Antarctic scientific and policy communities is proposed, with the ultimate goal of advancing the regulation and management of Antarctic tourism collaboratively.


Asunto(s)
Efectos Antropogénicos , Turismo , Regiones Antárticas , Ambiente , Humanos
6.
Proc Biol Sci ; 288(1948): 20203126, 2021 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-33823675

RESUMEN

Many ecological systems are now exposed to multiple stressors, and ecosystem management increasingly requires consideration of the joint effects of multiple stressors on focal populations, communities and ecosystems. In the absence of empirical data, ecosystem managers could use null models based on the combination of independently acting stressors to estimate the joint effects of multiple stressors. Here, we used a simulation study and a meta-analysis to explore the consequences of null model selection for the prediction of mortality resulting from exposure to two stressors. Comparing five existing null models, we show that some null models systematically predict lower mortality rates than others, with predicted mortality rates up to 67.5% higher or 50% lower than the commonly used Simple Addition model. However, the null model predicting the highest mortality rate differed across parameter sets, and therefore there is no general 'precautionary null model' for multiple stressors. Using a multi-model framework, we re-analysed data from two earlier meta-analyses and found that 54% of the observed joint effects fell within the range of predictions from the suite of null models. Furthermore, we found that most null models systematically underestimated the observed joint effects, with only the Stressor Addition model showing a bias for overestimation. Finally, we found that the intensity of individual stressors was the strongest predictor of the magnitude of the joint effect across all null models. As a result, studies characterizing the effects of individuals stressors are still required for accurate prediction of mortality resulting from multiple stressors.


Asunto(s)
Ecosistema , Simulación por Computador , Humanos
7.
Ecol Appl ; 30(7): e02143, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32335990

RESUMEN

Although three-dimensional (3D) seismic surveys have improved the success rate of exploratory drilling for oil and gas, the impacts have received little scientific scrutiny, despite affecting more area than any other oil and gas activity. To aid policy-makers and scientists, we reviewed studies of the landscape impacts of 3D-seismic surveys in the Arctic. We analyzed a proposed 3D-seismic program in northeast Alaska, in the northern Arctic National Wildlife Refuge, which includes a grid 63,000 km of seismic trails and additional camp-move trails. Current regulations are not adequate to eliminate impacts from these activities. We address issues related to the high-density of 3D trails compared to 2D methods, with larger crews, more camps, and more vehicles. We focus on consequences to the hilly landscapes, including microtopography, snow, vegetation, hydrology, active layers, and permafrost. Based on studies of 2D-seismic trails created in 1984-1985 in the same area by similar types of vehicles, under similar regulations, approximately 122 km2 would likely sustain direct medium- to high-level disturbance from the proposed exploration, with possibly expanded impacts through permafrost degradation and hydrological connectivity. Strong winds are common, and snow cover necessary to minimize impacts from vehicles is windblown and inadequate to protect much of the area. Studies of 2D-seismic impacts have shown that moist vegetation types, which dominate the area, sustain longer-lasting damage than wet or dry types, and that the heavy vehicles used for mobile camps caused the most damage. The permafrost is ice rich, which combined with the hilly topography, makes it especially susceptible to thermokarst and erosion triggered by winter vehicle traffic. The effects of climate warming will exacerbate the impacts of winter travel due to warmer permafrost and a shift of precipitation from snow to rain. The cumulative impacts of 3D-seismic traffic in tundra areas need to be better assessed, together with the effects of climate change and the industrial development that would likely follow. Current data needs include studies of the impacts of 3D-seismic exploration, better climate records for the Arctic National Wildlife Refuge, especially for wind and snow; and high-resolution maps of topography, ground ice, hydrology, and vegetation.


Asunto(s)
Hielos Perennes , Tundra , Alaska , Regiones Árticas , Nieve
8.
Conserv Biol ; 32(6): 1356-1367, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29956854

RESUMEN

The decline of coral cover on Australia's Great Barrier Reef (GBR) has largely been attributed to the cumulative pressures of tropical cyclones, temperature-induced coral bleaching, and predation by crown-of-thorns starfish (CoTS). In such a complex system, the effectiveness of any management intervention will become apparent only over decadal time scales. Systems modeling approaches are therefore essential to formulating and testing alternative management strategies. For a network of reefs, we developed a metacommunity model that incorporated the cumulative pressures of tropical cyclones, coral bleaching, predation, and competition between corals. We then tested the response of coral cover to management interventions including catchment restoration to reduce discharge onto the reef during cyclone-induced flood events and enhanced protection of trophic networks supporting predation of CoTS. Model results showed good agreement with long-term monitoring of the GBR, including cyclical outbreaks of CoTS driven by predator-prey dynamics on the network of reefs. Testing of intervention strategies showed that catchment restoration would likely improve coral cover. However, strategies that combined catchment restoration with enhanced CoTS predation were far more effective than catchment restoration alone.


Asunto(s)
Antozoos , Arrecifes de Coral , Animales , Australia , Conservación de los Recursos Naturales , Estrellas de Mar
9.
Glob Chang Biol ; 23(1): 28-41, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27507077

RESUMEN

Climate change is having a significant impact on ecosystem services and is likely to become increasingly important as this phenomenon intensifies. Future impacts can be difficult to assess as they often involve long timescales, dynamic systems with high uncertainties, and are typically confounded by other drivers of change. Despite a growing literature on climate change impacts on ecosystem services, no quantitative syntheses exist. Hence, we lack an overarching understanding of the impacts of climate change, how they are being assessed, and the extent to which other drivers, uncertainties, and decision making are incorporated. To address this, we systematically reviewed the peer-reviewed literature that assesses climate change impacts on ecosystem services at subglobal scales. We found that the impact of climate change on most types of services was predominantly negative (59% negative, 24% mixed, 4% neutral, 13% positive), but varied across services, drivers, and assessment methods. Although uncertainty was usually incorporated, there were substantial gaps in the sources of uncertainty included, along with the methods used to incorporate them. We found that relatively few studies integrated decision making, and even fewer studies aimed to identify solutions that were robust to uncertainty. For management or policy to ensure the delivery of ecosystem services, integrated approaches that incorporate multiple drivers of change and account for multiple sources of uncertainty are needed. This is undoubtedly a challenging task, but ignoring these complexities can result in misleading assessments of the impacts of climate change, suboptimal management outcomes, and the inefficient allocation of resources for climate adaptation.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales , Ecosistema , Clima , Humanos , Incertidumbre
10.
Glob Chang Biol ; 23(6): 2284-2296, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-27753179

RESUMEN

We have learned much about the impacts of warming on the productivity and distribution of marine organisms, but less about the impact of warming combined with other environmental stressors, including oxygen depletion. Also, the combined impact of multiple environmental stressors requires evaluation at the scales most relevant to resource managers. We use the Gulf of St. Lawrence, Canada, characterized by a large permanently hypoxic zone, as a case study. Species distribution models were used to predict the impact of multiple scenarios of warming and oxygen depletion on the local density of three commercially and ecologically important species. Substantial changes are projected within 20-40 years. A eurythermal depleted species already limited to shallow, oxygen-rich refuge habitat (Atlantic cod) may be relatively uninfluenced by oxygen depletion but increase in density within refuge areas with warming. A more stenothermal, deep-dwelling species (Greenland halibut) is projected to lose ~55% of its high-density areas under the combined impacts of warming and oxygen depletion. Another deep-dwelling, more eurythermal species (Northern shrimp) would lose ~4% of its high-density areas due to oxygen depletion alone, but these impacts may be buffered by warming, which may increase density by 8% in less hypoxic areas, but decrease density by ~20% in the warmest parts of the region. Due to local climate variability and extreme events, and that our models cannot project changes in species sensitivity to hypoxia with warming, our results should be considered conservative. We present an approach to effectively evaluate the individual and cumulative impacts of multiple environmental stressors on a species-by-species basis at the scales most relevant to managers. Our study may provide a basis for work in other low-oxygen regions and should contribute to a growing literature base in climate science, which will continue to be of support for resource managers as climate change accelerates.


Asunto(s)
Cambio Climático , Animales , Canadá , Clima , Ecosistema , Peces , Oxígeno , Dinámica Poblacional
11.
Biol Lett ; 13(3)2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28356409

RESUMEN

Changes in the Earth's environment are now sufficiently complex that our ability to forecast the emergent ecological consequences of ocean acidification (OA) is limited. Such projections are challenging because the effects of OA may be enhanced, reduced or even reversed by other environmental stressors or interactions among species. Despite an increasing emphasis on multifactor and multispecies studies in global change biology, our ability to forecast outcomes at higher levels of organization remains low. Much of our failure lies in a poor mechanistic understanding of nonlinear responses, a lack of specificity regarding the levels of organization at which interactions can arise, and an incomplete appreciation for linkages across these levels. To move forward, we need to fully embrace interactions. Mechanistic studies on physiological processes and individual performance in response to OA must be complemented by work on population and community dynamics. We must also increase our understanding of how linkages and feedback among multiple environmental stressors and levels of organization can generate nonlinear responses to OA. This will not be a simple undertaking, but advances are of the utmost importance as we attempt to mitigate the effects of ongoing global change.


Asunto(s)
Dióxido de Carbono/fisiología , Océanos y Mares , Organismos Acuáticos/fisiología , Dióxido de Carbono/toxicidad , Cambio Climático , Ecosistema , Concentración de Iones de Hidrógeno , Dinámica Poblacional , Agua de Mar/química
12.
Conserv Biol ; 31(6): 1428-1438, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28464304

RESUMEN

The proliferation of linear infrastructure such as roads and railways is a major global driver of cumulative biodiversity loss. One strategy for reducing habitat loss associated with development is to encourage linear infrastructure providers and users to share infrastructure networks. We quantified the reductions in biodiversity impact and capital costs under linear infrastructure sharing of a range of potential mine to port transportation links for 47 mine locations operated by 28 separate companies in the Upper Spencer Gulf Region of South Australia. We mapped transport links based on least-cost pathways for different levels of linear-infrastructure sharing and used expert-elicited impacts of linear infrastructure to estimate the consequences for biodiversity. Capital costs were calculated based on estimates of construction costs, compensation payments, and transaction costs. We evaluated proposed mine-port links by comparing biodiversity impacts and capital costs across 3 scenarios: an independent scenario, where no infrastructure is shared; a restricted-access scenario, where the largest mining companies share infrastructure but exclude smaller mining companies from sharing; and a shared scenario where all mining companies share linear infrastructure. Fully shared development of linear infrastructure reduced overall biodiversity impacts by 76% and reduced capital costs by 64% compared with the independent scenario. However, there was considerable variation among companies. Our restricted-access scenario showed only modest biodiversity benefits relative to the independent scenario, indicating that reductions are likely to be limited if the dominant mining companies restrict access to infrastructure, which often occurs without policies that promote sharing of infrastructure. Our research helps illuminate the circumstances under which infrastructure sharing can minimize the biodiversity impacts of development.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales/métodos , Ecosistema , Minería , Transportes , Conservación de los Recursos Naturales/economía , Costos y Análisis de Costo , Desarrollo Económico , Modelos Teóricos , Australia del Sur , Transportes/economía
13.
J Environ Manage ; 199: 229-241, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28549274

RESUMEN

Coastal environments are some of the most populated on Earth, with greater pressures projected in the future. Managing coastal systems requires the consideration of multiple uses, which both benefit from and threaten multiple ecosystem services. Thus understanding the cumulative impacts of human activities on coastal ecosystem services would seem fundamental to management, yet there is no widely accepted approach for assessing these. This study trials an approach for understanding the cumulative impacts of anthropogenic change, focusing on Tasman and Golden Bays, New Zealand. Using an expert elicitation procedure, we collected information on three aspects of cumulative impacts: the importance and magnitude of impacts by various activities and stressors on ecosystem services, and the causal processes of impact on ecosystem services. We assessed impacts to four ecosystem service benefits - fisheries, shellfish aquaculture, marine recreation and existence value of biodiversity-addressing three main research questions: (1) how severe are cumulative impacts on ecosystem services (correspondingly, what potential is there for restoration)?; (2) are threats evenly distributed across activities and stressors, or do a few threats dominate?; (3) do prominent activities mainly operate through direct stressors, or do they often exacerbate other impacts? We found (1) that despite high uncertainty in the threat posed by individual stressors and impacts, total cumulative impact is consistently severe for all four ecosystem services. (2) A subset of drivers and stressors pose important threats across the ecosystem services explored, including climate change, commercial fishing, sedimentation and pollution. (3) Climate change and commercial fishing contribute to prominent indirect impacts across ecosystem services by exacerbating regional impacts, namely sedimentation and pollution. The prevalence and magnitude of these indirect, networked impacts highlights the need for approaches like this to understand mechanisms of impact, in order to develop strategies to manage them.


Asunto(s)
Cambio Climático , Ecosistema , Explotaciones Pesqueras , Biodiversidad , Humanos , Nueva Zelanda
14.
Environ Manage ; 60(3): 484-495, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28497173

RESUMEN

Resource development projects typically result in monitoring programs that fail to fully consider the values and participation of surrounding communities. Also, monitoring protocols for single environmental values can be insufficient for addressing the cumulative impacts of resource development. Community-based environmental monitoring (CBEM) has emerged as a way to meaningfully include local citizens in the decision-making process and assessment of the development of natural resources. Our research explored how to develop effective and sustainable CBEM. Interviews were conducted with staff from 15 CBEM programs established across Canada to identify criteria of what constitutes effective CBEM. Results demonstrate that CBEM offers an effective, locally adapted, and culturally applicable approach to facilitate community participation in natural resource management and to track environmental change. Benefits of CBEM include: locally relevant monitoring protocols, inclusion of cumulative impacts, better informed decision-making, and increased awareness and collaboration amongst community, governments, and proponents. Challenges associated with CBEM are cost, capacity, longevity, distribution of results, and establishing credibility. This research validates the use of CBEM for improving resource management.


Asunto(s)
Participación de la Comunidad , Conservación de los Recursos Naturales/métodos , Monitoreo del Ambiente/métodos , Canadá , Toma de Decisiones , Humanos , Investigación , Encuestas y Cuestionarios
15.
Glob Chang Biol ; 22(1): 180-9, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26149723

RESUMEN

The accelerating rate of global change has focused attention on the cumulative impacts of novel and extreme environmental changes (i.e. stressors), especially in marine ecosystems. As integrators of local catchment and regional processes, freshwater ecosystems are also ranked highly sensitive to the net effects of multiple stressors, yet there has not been a large-scale quantitative synthesis. We analysed data from 88 papers including 286 responses of freshwater ecosystems to paired stressors and discovered that overall, their cumulative mean effect size was less than the sum of their single effects (i.e. an antagonistic interaction). Net effects of dual stressors on diversity and functional performance response metrics were additive and antagonistic, respectively. Across individual studies, a simple vote-counting method revealed that the net effects of stressor pairs were frequently more antagonistic (41%) than synergistic (28%), additive (16%) or reversed (15%). Here, we define a reversal as occurring when the net impact of two stressors is in the opposite direction (negative or positive) from that of the sum of their single effects. While warming paired with nutrification resulted in additive net effects, the overall mean net effect of warming combined with a second stressor was antagonistic. Most importantly, the mean net effects across all stressor pairs and response metrics were consistently antagonistic or additive, contrasting the greater prevalence of reported synergies in marine systems. Here, a possible explanation for more antagonistic responses by freshwater biota to stressors is that the inherent greater environmental variability of smaller aquatic ecosystems fosters greater potential for acclimation and co-adaptation to multiple stressors.


Asunto(s)
Ecosistema , Agua Dulce , Estrés Fisiológico , Aclimatación , Biodiversidad , Biota , Cambio Climático , Nitrificación
16.
Proc Biol Sci ; 282(1813): 20151053, 2015 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-26246548

RESUMEN

Species around the world have suffered collapses, and a key question is why some populations are more vulnerable than others. Traditional conservation biology and evidence from terrestrial species suggest that slow-growing populations are most at risk, but interactions between climate variability and harvest dynamics may alter or even reverse this pattern. Here, we test this hypothesis globally. We use boosted regression trees to analyse the influences of harvesting, species traits and climate variability on the risk of collapse (decline below a fixed threshold) across 154 marine fish populations around the world. The most important factor explaining collapses was the magnitude of overfishing, while the duration of overfishing best explained long-term depletion. However, fast growth was the next most important risk factor. Fast-growing populations and those in variable environments were especially sensitive to overfishing, and the risk of collapse was more than tripled for fast-growing when compared with slow-growing species that experienced overfishing. We found little evidence that, in the absence of overfishing, climate variability or fast growth rates alone drove population collapse over the last six decades. Expanding efforts to rapidly adjust harvest pressure to account for climate-driven lows in productivity could help to avoid future collapses, particularly among fast-growing species.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales , Explotaciones Pesqueras , Peces/fisiología , Animales , Extinción Biológica , Peces/crecimiento & desarrollo , Océanos y Mares , Dinámica Poblacional , Riesgo
17.
Glob Chang Biol ; 20(4): 1211-24, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24339207

RESUMEN

Many areas of the Arctic are simultaneously affected by rapid climate change and rapid industrial development. These areas are likely to increase in number and size as sea ice melts and abundant Arctic natural resources become more accessible. Documenting the changes that have already occurred is essential to inform management approaches to minimize the impacts of future activities. Here, we determine the cumulative geoecological effects of 62 years (1949-2011) of infrastructure- and climate-related changes in the Prudhoe Bay Oilfield, the oldest and most extensive industrial complex in the Arctic, and an area with extensive ice-rich permafrost that is extraordinarily sensitive to climate change. We demonstrate that thermokarst has recently affected broad areas of the entire region, and that a sudden increase in the area affected began shortly after 1990 corresponding to a rapid rise in regional summer air temperatures and related permafrost temperatures. We also present a conceptual model that describes how infrastructure-related factors, including road dust and roadside flooding are contributing to more extensive thermokarst in areas adjacent to roads and gravel pads. We mapped the historical infrastructure changes for the Alaska North Slope oilfields for 10 dates from the initial oil discovery in 1968-2011. By 2010, over 34% of the intensively mapped area was affected by oil development. In addition, between 1990 and 2001, coincident with strong atmospheric warming during the 1990s, 19% of the remaining natural landscapes (excluding areas covered by infrastructure, lakes and river floodplains) exhibited expansion of thermokarst features resulting in more abundant small ponds, greater microrelief, more active lakeshore erosion and increased landscape and habitat heterogeneity. This transition to a new geoecological regime will have impacts to wildlife habitat, local residents and industry.


Asunto(s)
Ecosistema , Monitoreo del Ambiente/métodos , Yacimiento de Petróleo y Gas , Alaska , Regiones Árticas , Cambio Climático , Hielo , Suelo , Temperatura
18.
Sci Total Environ ; 914: 169940, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38199351

RESUMEN

Knowledge about the cumulative impacts of anthropogenic activities and environmental conditions on marine ecosystems is incomplete and details are lacking. Compositional community changes can occur along gradients, and community data can be used to assess the state of community resilience against combined impacts of variables representing human pressures and environmental conditions. Here we use a machine learning approach, i.e., Gradient Forest, to identify explanatory variable thresholds and select relevant epibenthic fauna and demersal fish species, which can be used to inform an integrated management of multiple human pressures and conservation planning in the southern North Sea. We show that a broad selection of anthropogenic and environmental variables, such as natural disturbance of the seafloor and euphotic depth, determined community composition thresholds of 67 epibenthic fauna and 39 demersal fish species along environmental conditions and human pressure gradients in the southern North Sea between 2010 and 2020. This has the potential to inform resilience assessments under the Marine Strategy Framework Directive to promote and retain a good environmental status of marine ecosystems.


Asunto(s)
Ecosistema , Bosques , Humanos , Animales , Peces , Mar del Norte
19.
R Soc Open Sci ; 11(4): 240058, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38633351

RESUMEN

This review comprehensively evaluates the impacts of anthropogenic threats on beaked whales (Ziphiidae)-a taxonomic group characterized by cryptic biology, deep dives and remote offshore habitat, which have challenged direct scientific observation. By synthesizing information published in peer-reviewed studies and grey literature, we identified available evidence of impacts across 14 threats for each Ziphiidae species. Threats were assessed based on their pathways of effects on individuals, revealing many gaps in scientific understanding of the risks faced by beaked whales. By applying a comprehensive taxon-level analysis, we found evidence that all beaked whale species are affected by multiple stressors, with climate change, entanglement and plastic pollution being the most common threats documented across beaked whale species. Threats assessed as having a serious impact on individuals included whaling, military sonar, entanglement, depredation, vessel strikes, plastics and oil spills. This review emphasizes the urgent need for targeted research to address a range of uncertainties, including cumulative and population-level impacts. Understanding the evidence and pathways of the effects of stressors on individuals can support future assessments, guide practical mitigation strategies and advance current understanding of anthropogenic impacts on rare and elusive marine species.

20.
Mar Pollut Bull ; 200: 116091, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38335632

RESUMEN

Multiple stressors often act concomitantly on ecosystems but detection of species responses follows the "single species-single driver" strategy, and cumulative impacts are seldom considered. During 1990-2010, multiple perturbations in the Caspian Sea, led to the decline of kilka, sturgeon and Caspian seal populations. Specific causes for their collapse were identified but a cumulative assessment has never been carried out. Using loop analysis, a qualitative modelling technique suitable in poor-data contexts, we show how multiple drivers can be combined to assess their cumulative impact. We confirm that the decline of kilka, sturgeon and Caspian seal populations is compatible with a net effect of the concomitant perturbations. Kilkas collapse was certainly due to the outburst of M. leidyi and overfishing. In addition, the excess nutrient might have conspired to reduce these populations. The interplay between concurrent drivers produces trade-offs between opposite effects and ecosystem management must face this challenge.


Asunto(s)
Ecosistema , Phocidae , Animales , Mar Caspio , Conservación de los Recursos Naturales , Explotaciones Pesqueras , Peces
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