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101.
Public engagement is important to invasive species management, and recreational harvest programs are one way agencies seek to involve the public and raise awareness. We surveyed participants (n = 660) and non-participants (n = 77) in the 2013 Python ChallengeTM to understand whether this event achieved its primary goal of raising awareness of the ecological impact of Burmese pythons (Python molurus bivittatus) in south Florida. Respondents indicated a high level of ‘concern’ about the seriousness of the python problem and the need for management actions. Concern was affected positively by environmental motivations, experience of seeing pythons in the wild, older age, and female sex, but negatively by level of Python Challenge involvement. Results suggest that ‘proximate’ experience of not seeing a python may reduce concern, whereas ‘ongoing’ experience may temper concern without diminishing involvement. This research highlights the role of experience in shaping beliefs and advises diligence in public participation programs.  相似文献   
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Significant differences occur between results of chamber work conducted outdoors versus work conducted indoors under constant light intensity. Under outdoor conditions at constant [NOX]O, lower [HC]o resulted in lower [NO2]max and NO2 dosage during the daylight hours. The percent reduction in [NO2]max was a function of the [HC]0 reduction and the [NOX]O level. Under all experimental conditions the 10 hour N02 average to maximum N02 concentration ratio appeared to be constant at 0.73 during the daylight hours. A regression equation relating [NOx]max to [NOX]O, [HC]O, and measures of solar radiation accounted for 92% of the variance in the data. Although there is unavoidable confoundment between [HC]0 and solar radiation, the HC term in this regression equation can introduce ±20 % change in [N02]max - This variation can be partially offset or enhanced by variations in solar radiation.  相似文献   
104.
We present data on the distributional changes within an order of macroinvertebrates used in biological water quality monitoring. The British Odonata (dragonflies and damselflies) have been shown to be expanding their range northwards and this could potentially affect the use of water quality metrics. The results show that the families of Odonata that are used in monitoring are shifting their ranges poleward and that species richness is increasing through time at most UK latitudes. These past distributional shifts have had negligible effects on water quality indicators. However, variation in Odonata species richness (particularly in species-poor regions) has a significant effect on water quality metrics. We conclude with a brief review of current and predicted responses of aquatic macroinvertebrates to environmental warming and maintain that caution is warranted in the use of such dynamic biological indicators.  相似文献   
105.
There are a number of agricultural farming practices that are controversial. These may include using chemical fertilizers, pesticides, and herbicides, and planting genetically modified crops, as well as the decision to dehorn cattle rather than raise polled cattle breeds. We use data from a survey of Missouri crop and livestock producers to determine whether a farmer’s ethical framework affects his or her decision to engage in these practices. We find that a plurality of farmers prefer an agricultural policy that reflects principles based on rights rather than principles of utilitarianism or justice. Furthermore, after controlling for personal and farm characteristics, we find a positive correlation between farmers preferring a rights-based policy and a farmer’s use of chemical farm inputs and polled rather than horned cattle. We also find that a combination of ethical framework and farm and farmer characteristics correlate with decisions to use farm chemicals, while only farm and farmer characteristics affect the decision to plant GM crops and only a farmer’s ethical framework affects the decision to use polled cattle.  相似文献   
106.
In this paper we consider the question of whether middle-scale farmers, which we define as producers generating between 100,000 and100,000 and 250,000 in sales annually, are better agricultural stewards than small and large-scale producers. Our study is motivated by the argument of some commentators that farmers of this class ought to be protected in part because of the unique attitudes and values they possess regarding what constitutes a “good farmer.” We present results of a survey of Missouri farmers designed to assess farmer attitudes and values regarding a variety of indicators of farmer stewardship, such as the most important issues in agriculture, environment, and treatment of farm animals, perspectives on the past and future of agriculture, and ethical behavior. We find little evidence that farmers-of-the-middle are particularly noteworthy in these regards. We do find evidence, however, that middle-scale farmers are more pessimistic and anxious about their role in the future of agriculture.  相似文献   
107.
Global sea-level rise and coastal vulnerability   总被引:1,自引:0,他引:1  
  相似文献   
108.
In many temperate regions, fuel and oil spills are sometimes managed simply by allowing natural degradation to occur, while monitoring soils and groundwater to ensure that there is no off-site migration or on-site impact. To critically assess whether this approach is suitable for coastal Antarctic sites, we investigated the extent of evaporation and biodegradation at three old fuel spills at Casey Station. Where the contaminants migrated across frozen ground, probably beneath snow, approximately half the fuel evaporated in the first few months prior to infiltration at the beginning of summer. Once in the ground, however, evaporation rates were negligible. In contrast, minor spills from fuel drums buried in an abandoned waste disposal site did not evaporate to the same extent. Biodegradation within all three spill sites is generally very minor. We conclude that natural attenuation is not a suitable management strategy for fuel-contaminated soils in Antarctic coastal regions.  相似文献   
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