Most studies assessing the combined effects of chemical and non-chemical stressors on aquatic ecosystems have been based on synchronous stressor applications. However, asynchronous exposure scenarios ...may be more common in nature, particularly for pulsed stressors such as heatwaves and pesticide concentration peaks. In this study, we investigated the single and combined effects of the insecticide chlorpyrifos (CPF) and a heatwave (HW) on a zooplankton community representative of a Mediterranean coastal wetland using synchronous (CPF+HW) and asynchronous (HW→CPF and CPF→HW) exposure scenarios. CPF was applied at a concentration of 0.8 µg/L (single pulse), and the HW was simulated by a temperature increase of 8°C above the control temperature (20°C) for 7 days in freshwater microcosms. The interaction between stressors in synchrony resulted in synergistic effects at the population level (Daphnia magna) and additive at the community level. The partial reduction of sensitive species resulted in an abundance increase of competing species that were more tolerant to the evaluated stressors (e.g. Moina sp.). The asynchronous exposure scenarios resulted in a similar abundance decline of sensitive populations as compared to the synchronous one; however, the timing of stressor resulted in different responses in the long term. In the HW→CPF treatment, the D. magna population recovered at least one month faster than in the CPF+HW treatment, probably due to survival selection and cross-tolerance mechanisms. In the CPF→HW treatment, the effects lasted longer than in the CPF+HW, and the population did not recover within the experimental period, most likely due to the energetic costs of detoxification and effects on internal damage recovery. The different timing and magnitude of indirect effects among the tested asynchronous scenarios resulted in more severe effects on the structure of the zooplankton community in the CPF→HW treatment. Our study highlights the relevance of considering the order of stressors to predict the long-term effects of chemicals and heatwaves both at the population and community levels.
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•Chlorpyrifos and heatwaves can produce synergistic effects on zooplankton species.•The order of stressors affects the long-term response of sensitive species.•Effects of the stressor sequence are propagated at the community level.•Chlorpyrifos followed by heatwaves produce the most harmful effects.•The stressor´s timing should be considered in multiple stressors research.
Most research assumes that job stressors decrease employees’ voice behavior. However, looking at research about job stressors and OCB (including voice), not all types of stressors have the same ...effects. The purpose of our research is to develop a new research model relating to the different effects of challenge stressors and hindrance stressors on voice behavior. Drawing on ego depletion theory, we propose that the relationship between stressors and voice behavior is mediated by employees’ ego depletion change. Further, we tested the moderating effect of leader-member exchange (LMX) on the relationship between stressors and subsequent ego depletion. We examined the hypothesized relationships using data collected in China from 346 employees on three consecutive days. As hypothesized, we found that ego depletion mediates the relationship between stressors and voice behavior. Also, LMX strengthens the positive relationship between hindrance stressors and subsequent ego depletion. We discuss implications for research and practice.
•A people-environment framework to evaluate transport stress.•28 environmental stressors, 9 personal stressors, 4 time stressors and 6 stated stress responses examined.•A large-scale city-wide survey ...with 5,908 bus commuters conducted.•The average transport stress level is lower than money, work and family stress but higher than relationship stress.•Bus stop environment, crowding, public transport etiquette and accurate time of arrival are to be addressed with high priority.
Based on the people-environment conceptual framework, this paper measures the level of transport stress experienced by bus commuters and examines its relationship with a wide range of environmental and personal stressors, as well as different stress responses. A total of 28 environmental stressors, 9 personal stressors, 4 time-related stressors and 6 stated stress responses are examined. The data were collected through a large-scale online questionnaire survey among bus commuters of a major franchised bus company in Hong Kong (n = 5,908). A factor analysis and a structural equation model (SEM) are conducted to unveil the interlinkages among bus-related environmental stressors, personal stressors, travel characteristics, perceived transport stress and stated stress responses. Results indicate that bus commuters reported an average stress level of 47.10 out of 100 (SD = 29.50). The average transport stress level is lower than money, work and family stress but higher than relationship stress. Spatially, there are great variations within the city, with notably higher stress levels for some new towns in Northwest New Territories and the central business district during evening commutes. Based on the SEM results, the number of bus transfers (β = 0.05) and travel time (β = 0.06) are strongly associated with transport stress. Poor bus stop environment (β = 0.14), crowding at bus stops and compartments (β = 0.13), hostile attitudes of passengers and drivers (β = 0.08), and unreliable waiting and travel time (β = 0.08) are important environmental stressors. Many of these factors have not been closely examined in previous studies. In relation to health, transport stress is positively associated with negative physical (β = 0.43) and emotional (β = 0.48) responses. Feeling exhausted, irritated and anxiety were the most commonly reported responses to transport stress. To enhance bus commutes, priorities should be given to improving the bus stop environment, reducing crowding throughout the bus journeys, and alleviating road congestion. Overall, the empirical findings from this large-scale study on transport stress can help governments to formulate targeted measures to enhance the quality of public transit services and to support sustainable urban transport.
The COVID-19 pandemic and its consequences have been associated with an increase in poor population mental health. We assessed how depressive symptoms changed among U.S. adults over the course of the ...COVID-19 pandemic and identified the key risk factors for these symptoms.
Longitudinal panel study of a nationally representative group of U.S. adults ages 18 years and older surveyed in March-April 2020 (Time 1; N=1441) and March-April 2021 (Time 2; N=1161) in the COVID-19 and Life Stressors Impact on Mental Health and Well-being study (CLIMB). The Patient Health Questionnaire-9 (PHQ-9) was used to define elevated depressive symptoms (cut-off ≥10) and depressive symptoms score (0-27).
The prevalence of elevated depressive symptoms persisted from 27.8% in 2020 (95% CI: 24.9, 30.9) to 32.8% in 2021 (95% CI: 29.1, 36.8). Over time, the central drivers of depressive symptoms were low household income, not being married, and experiencing multiple stressors during the COVID-19 pandemic. The odds ratio of elevated depressive symptoms for low income relative to high income persons increased from 2.3 (95% CI: 1.2, 4.2) in 2020 to 7.0 (95% CI: 3.7, 13.3) in 2021. Fewer people reported experiencing 4 or more COVID-19 stressors in 2021 than in 2020 (47.5% in 2020 vs 37.1% in 2021), but the odds ratio of elevated depressive symptoms associated with 4 or more stressors relative to 1 stressor or less increased from 1.9 (95% CI: 1.2, 3.1) in 2020 to 5.4 (95% CI: 3.2, 9.2) in 2021.
The burden of depressive symptoms in the U.S. adult population increased over the course of the COVID-19 pandemic. Mental health gaps grew between populations with different assets and stressor experiences during the COVID-19 pandemic.
CLIMB Time 1 was sponsored by the Rockefeller Foundation-Boston University 3-D Commission. CLIMB Time 2 was sponsored by the de Beaumont Foundation.
Analysis of cumulative human impacts in the marine environment is still in its infancy but developing rapidly. In this study, existing approaches were expanded upon, aiming for a realistic ...consideration of cumulative impacts at a regional scale. Thirty-eight human activities were considered, with each broken down according to stressor types and a range of spatial influences. To add to the policy relevance, existing stressors within and outside of conservation areas were compared. Results indicate the entire continental shelf of Canada's Pacific marine waters is affected by multiple human activities at some level. Commercial fishing, land-based activities and marine transportation accounted for 57.0%, 19.1%, and 17.7% of total cumulative impacts, respectively. Surprisingly, most areas with conservation designations contained higher impact scores than the mean values of their corresponding ecoregions. Despite recent advances in mapping cumulative impacts, many limitations remain. Nonetheless, preliminary analyses such as these can provide information relevant to precautionary management and conservation efforts.
Enterprise social networking (ESN) techniques have been widely adopted by organizations to provide a platform for public communication among employees. Based on the job demand–control–support model ...and communication visibility theory, this study investigates how the relationships between the perceived work stressors of employees (i.e., challenge and hindrance stressors) and their creativity are moderated by team task- and relationship-oriented ESN usage. We used the hierarchical linear model to test this multilevel model. Results of a survey of 260 employees in 72 groups indicate that two ESN usage types differentially moderate the relationship between work stressors and employee creativity. Specifically, task-oriented ESN usage positively moderates the effects of the two types of stressors on employee creativity, whereas relationship-oriented ESN usage negatively moderates the relationship between hindrance stressors and employee creativity. Theoretical and practical implications are also discussed.
The COVID‐19 pandemic has created a variety of stressors, some of which have been linked to intense stress reactions, such as posttraumatic stress (PTS)‐like symptoms. However, we have limited ...knowledge on cumulative effects of pandemic‐related stressors on PTS or on variables that may mitigate the effects of these stressors. We aimed to address some of these knowledge gaps by testing three models to examine the interrelationships among pandemic‐related stressors, perceived social support, coping flexibility, and pandemic‐related PTS. The sample of this cross‐sectional correlational study is comprised of 2291 adults from the United States who completed an online survey between 22 May 2020 and 15 July 2020. Results indicated that greater exposure to secondary stressors, but not COVID‐19‐related stressors, was associated with increased PTS. After controlling for COVID‐19‐related and secondary stressors, social support had negative direct and indirect (via coping flexibility) effects on PTS. In addition, social support mediated the effects of COVID‐19‐related and secondary stressors on PTS. Our findings highlight the complexity of the role of social support in relation to pandemic‐related stressors and PTS, and suggest that early interventions that target social support and coping flexibility may help reduce pandemic‐related PTS.
The earth is now subject to climate change and habitat deterioration on unprecedented scales. Monitoring climate change and habitat loss alone is insufficient if we are to understand the effects of ...these factors on complex biological communities. It is therefore important to identify bioindicator taxa that show measurable responses to climate change and habitat loss and that reflect wider-scale impacts on the biota of interest. We argue that bats have enormous potential as bioindicators: they show taxonomic stability, trends in their populations can be monitored, short- and long-term effects on populations can be measured and they are distributed widely around the globe. Because insectivorous bats occupy high trophic levels, they are sensitive to accumulations of pesticides and other toxins, and changes in their abundance may reflect changes in populations of arthropod prey species. Bats provide several ecosystem services, and hence reflect the status of the plant populations on which they feed and pollinate as well as the productivity of insect communities. Bat populations are affected by a wide range of stressors that affect many other taxa. In particular, changes in bat numbers or activity can be related to climate change (including extremes of drought, heat, cold and precipitation, cyclones and sea level rise), deterioration of water quality, agricultural intensification, loss and fragmentation of forests, fatalities at wind turbines, disease, pesticide use and overhunting. There is an urgent need to implement a global network for monitoring bat populations so their role as bioindicators can be used to its full potential.
Based on previous research, the conceptual model presenting the interaction between transformational leadership, challenge-hindrance stressors and thriving at work was constructed and used to ...generate the hypotheses for the study. Data were obtained from 542 questionnaires distributed across different organizations. The participants included ordinary employees, grassroots middle and senior managers from China. The major findings are as follows. First, transformational leadership directly is positively related to challenge stressors and thriving at work. Second, challenge stressors are positively relate to thriving at work, while hindrance stressors are negatively relate to thriving at work. Furthermore, challenge stressors mediate the relationship between transformational leadership and thriving at work. Given these findings, the study examined the moderating effect of supervisor developmental feedback on the relationship between transformational leadership and thriving at work. Results reveal that supervisor developmental feedback plays a positive regulatory role between challenge stressors and thriving at work. Additionally, it is shown that the mediating effect of challenge stressors on the relationship between transformational leadership and thriving at work is moderated by supervisor developmental feedback.
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