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101.

Agrochemicals including neonicotinoid insecticides and fungicides are frequently applied as seed treatments on corn, soybeans, and other common row crops. Crops grown from pesticide-treated seed are often directly planted in managed floodplain wetlands and used as a soil disturbance or food resource for wildlife. We quantified invertebrate communities within mid-latitude floodplain wetlands and assessed their response to use of pesticide-treated seeds within the floodplain. We collected and tested aqueous and sediment samples for pesticides in addition to sampling aquatic invertebrates from 22 paired wetlands. Samples were collected twice in 2016 (spring [pre-water level drawdown] and autumn [post-water level flood-up]) followed by a third sampling period (spring 2017). Meanwhile, during the summer of 2016, a portion of study wetlands were planted with either pesticide-treated or untreated corn seed. Neonicotinoid toxic equivalencies (NI-EQs) for sediment (X??=?0.58 μg/kg), water (X??=?0.02 μg/L), and sediment fungicide concentrations (X??=?0.10 μg/kg) were used to assess potential effects on wetland invertebrates. An overall decrease in aquatic insect richness and abundance was associated with greater NI-EQs in wetland water and sediments, as well as with sediment fungicide concentration. Post-treatment, treated wetlands displayed a decrease in insect taxa-richness and abundance before recovering by the spring of 2017. Information on timing and magnitude of aquatic insect declines will be useful when considering the use of seed treatments for wildlife management. More broadly, this study brings attention to how agriculture is used in wetland management and conservation planning.

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Small-bodied fishes are more commonly being used in environmental effects monitoring (EEM) studies. There is a lack of understanding of the biological characteristics of many small-bodied species, which hinders study designs for monitoring studies. For example, 72 % of fish population surveys in Canada’s EEM program for pulp and paper mills that used small-bodied fishes were conducted outside of the reproductive period of the species. This resulted in an inadequate assessment of the EEM program’s primary effect endpoint (reproduction) for these studies. The present study examined seasonal changes in liver size, gonad size, and condition in seven freshwater and estuarine small-bodied fishes in Atlantic Canada. These data were used to examine differences in reproductive strategies and patterns of energy storage among species. Female gonadal recrudescence in all seven species began primarily in the 2-month period in the spring before spawning. Male gonadal development was concurrent with females in five species; however, gonadal recrudescence began in the fall in male three-spined stickleback (Gasterosteus aculeatus) and slimy sculpin (Cottus cognatus). The spawning period for each species was estimated from the decline in relative ovary size after its seasonal maximum value in spring. The duration of the spawning period reflected the reproductive strategy (single vs multiple spawning) of the species. Optimal sampling periods to assess reproductive impacts in each species were determined based on seasonal changes in ovary size and were identified to be during the prespawning period when gonads are developing and variability in relative gonad size is at a minimum.  相似文献   
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We attempt to understand, scientifically, how different members of the mining concession, impacted communities, and government authorities behave when a conflicting situation arises. The main purpose of our effort is to start developing a framework for the scientific modeling of stakeholders’ behavior, and we create a reality-driven generic scenario of conflict. We assume that the managers and superintendants of a mining operation currently envision a problem; one that tests the limits of the commitment of the company’s mission statement, and of the spectrum of actions taken which are embedded in the “culture” of the company’s corporate social responsibility. It is an “event” that highlights the nature of an overall problem that the company would like to predict and act proactively: the integration of scientific tools, sustainability, and cultural realities within a mining framework. We adapt an agent-based modeling approach and start with a theoretical understanding of certain social behavior, build a model, and simulate “what if” scenarios to understand its dynamics to gain a better insight of the complexity of a seemingly simple social system of interest.  相似文献   
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This is a companion paper to an earlier work in which an agent-based model is proposed by Nakagawa et al. for exploring the emergent phenomena of social license to operate (SLO) of a mining company. In this paper, the structure of the original model is described, along with the enhanced ability for the two-way diffusion of information and opinion among agents. This is achieved through the addition of a global “dialogue” variable, which dictates the extent to which higher influence agents accept opinion from agents of lower influence. Initial findings suggest that the bidirectional diffusion of information has a large effect on the time that the modelling population takes to reach a Social License consensus, and the effect is especially pronounced for low dialogue values. In other words, the Social License of communities characterized by a low preference for dialogue (as opposed to “top-down” mandated communication) will be largely affected by small changes in the preference for dialogue. Findings also suggest that as a modelling community becomes more and more open to dialogue, the effect on the time to consensus becomes less and less pronounced until it becomes negligible at a fairly low dialogue level.  相似文献   
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PROBLEM: It is estimated that 5 to 10 arc flash explosions occur in electric equipment every day in the United States. In the mining industry the largest single injury category of electrical injuries are caused by non-contact electrical arcs. METHOD: This investigation progressed in two phases: (a) 836 Mine Safety and Health Administration (MSHA) reports of electric arcing incidents that occurred over a period of 11 years were reviewed, and (b) personal interviews were conducted with 32 individuals. A theoretical Safe Job Performance Model guided the study. RESULTS: Behavioral dimensions were identified and included the effect of worker experience, judgment and decision-making ability, behavioral and organizational controls, and safety culture. SUMMARY: The National Institute for Occupational Safety and Health (NIOSH) conducted an investigation of behavioral components associated with arc flash incidents and developed recommendations for interventions based on findings. IMPACT ON INDUSTRY: This study fills a vacuum in electrical training with a focus on the organizational and behavioral aspects of arc flash incidents. The research is cross-cutting in its scope, in that the results apply not only to mining and construction, but many other industries employing electricians. Although the majority of mine electrical injuries are the results of burns from electrical arcs, few miners are aware that such a hazard exists. A safety training program, which includes a video and an instructor's discussion guide, was developed for electricians based on this study's findings. "Arc Flash Awareness" was released in 2007 (DHHS NIOSH Publication No.2007-116D) and is available through 1-800 CDC INFO. Phone: 1-800 232-4636 or email cdcinfo@cdc.gov. It is also available from MSHA at MSHADistribution@dol.gov or 304-256-3257 (DVD-576). Private industry is producing Portuguese and Spanish language translations.  相似文献   
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