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801.
Conservation policy in agricultural systems in the United States relies primarily on voluntary action by farmers. Federal conservation programs, including the Environmental Quality Incentives Program, offer incentives, both financial and technical, to farmers in exchange for adoption of conservation practices. Understanding motivations for (as well as barriers to) participation in voluntary programs is important for the design of future policy and effective outreach. While a significant literature has explored motivations and barriers to conservation practice adoption and participation in single programs, few studies in the U.S. context have explored general participation by farmers in one place and time. A mixed-methods research approach was utilized to explore farmer participation in all U.S. Farm Bill programs in Indiana. Current and past program engagement was high, with nearly half of survey respondents reporting participation in at least one program. Most participants had experience with the Conservation Reserve Program, with much lower participation rates in other programs. Most interview participants who had experience in programs were motivated by the environmental benefits of practices, with incentives primarily serving to reduce the financial and technical barriers to practice adoption. The current policy arrangement, which offers multiple policy approaches to conservation, offers farmers with different needs and motivations a menu of options. However, evidence suggests that the complexity of the system may be a barrier that prevents participation by farmers with scarce time or resources. Outreach efforts should focus on increasing awareness of program options, while future policy must balance flexibility of programs with complexity.  相似文献   
802.

The development of high-resolution greenhouse gas (GHG) inventories is an important step towards emission reduction in different sectors. However, most of the spatially explicit approaches that have been developed to date produce outputs at a coarse resolution or do not disaggregate the data by sector. In this study, we present a methodology for assessing GHG emissions from the residential sector by settlements at a fine spatial resolution. In many countries, statistical data about fossil fuel consumption is only available at the regional or country levels. For this reason, we assess energy demand for cooking and water and space heating for each settlement, which we use as a proxy to disaggregate regional fossil fuel consumption data. As energy demand for space heating depends heavily on climatic conditions, we use the heating degree day method to account for this phenomenon. We also take the availability of energy sources and differences in consumption patterns between urban and rural areas into account. Based on the disaggregated data, we assess GHG emissions at the settlement level using country and regional specific coefficients for Poland and Ukraine, two neighboring countries with different energy usage patterns. In addition, we estimate uncertainties in the results using a Monte Carlo method, which takes uncertainties in the statistical data, calorific values, and emission factors into account. We use detailed data on natural gas consumption in Poland and biomass consumption for several regions in Ukraine to validate our approach. We also compare our results to data from the EDGAR (Emissions Database for Global Atmospheric Research), which shows high agreement in places but also demonstrates the advantage of a higher resolution GHG inventory. Overall, the results show that the approach developed here is universal and can be applied to other countries using their statistical information.

  相似文献   
803.
Numerous studies have demonstrated that entomophagous arthropods use herbivore-induced plant volatile (HIPV) blends to search for their prey or host. However, no study has yet focused on the response of nocturnal predators to volatile blends emitted by prey damaged plants. We investigated the olfactory behavioral responses of the night-active generalist predatory earwig Doru luteipes Scudder (Dermaptera: Forficulidae) to diurnal and nocturnal volatile blends emitted by maize plants (Zea mays) attacked by either a stem borer (Diatraea saccharalis) or a leaf-chewing caterpillar (Spodoptera frugiperda), both suitable lepidopteran prey. Additionally, we examined whether the earwig preferred odors emitted from short- or long-term damaged maize. We first determined the earwig diel foraging rhythm and confirmed that D. luteipes is a nocturnal predator. Olfactometer assays showed that during the day, although the earwigs were walking actively, they did not discriminate the volatiles of undamaged maize plants from those of herbivore damaged maize plants. In contrast, at night, earwigs preferred volatiles emitted by maize plants attacked by D. saccharalis or S. frugiperda over undamaged plants and short- over long-term damaged maize. Our GC-MS analysis revealed that short-term damaged nocturnal plant volatile blends were comprised mainly of fatty acid derivatives (i.e., green leaf volatiles), while the long-term damaged plant volatile blend contained mostly terpenoids. We also observed distinct volatile blend composition emitted by maize damaged by the different caterpillars. Our results showed that D. luteipes innately uses nocturnal herbivore-induced plant volatiles to search for prey. Moreover, the attraction of the earwig to short-term damaged plants is likely mediated by fatty acid derivatives.  相似文献   
804.
Efficient and economic reuse of waste is one of the pillars of modern environmental engineering. In the field of domestic sewage management, source separation of yellow (urine), brown (faecal matter) and grey waters aims to recover the organic substances concentrated in brown water, the nutrients (nitrogen and phosphorous) in the urine and to ensure an easier treatment and recycling of grey waters. With the objective of emphasizing the potential of recovery of resources from sewage management, a lab-scale research study was carried out at the University of Padova in order to evaluate the performances of oleaginous plants (suitable for biodiesel production) in the phytotreatment of source separated yellow and grey waters. The plant species used were Brassica napus (rapeseed), Glycine max (soybean) and Helianthus annuus (sunflower). Phytotreatment tests were carried out using 20 L pots. Different testing runs were performed at an increasing nitrogen concentration in the feedstock. The results proved that oleaginous species can conveniently be used for the phytotreatment of grey and yellow waters from source separation of domestic sewage, displaying high removal efficiencies of nutrients and organic substances (nitrogen > 80%; phosphorous > 90%; COD nearly 90%). No inhibition was registered in the growth of plants irrigated with different mixtures of yellow and grey waters, where the characteristics of the two streams were reciprocally and beneficially integrated.  相似文献   
805.
A model is developed to enable estimation of chloramine demand in full scale drinking water supplies based on chemical and microbiological factors that affect chloramine decay rate via nonlinear regression analysis method. The model is based on organic character (specific ultraviolet absorbance (SUVA)) of the water samples and a laboratory measure of the microbiological (F m ) decay of chloramine. The applicability of the model for estimation of chloramine residual (and hence chloramine demand) was tested on several waters from different water treatment plants in Australia through statistical test analysis between the experimental and predicted data. Results showed that the model was able to simulate and estimate chloramine demand at various times in real drinking water systems. To elucidate the loss of chloramine over the wide variation of water quality used in this study, the model incorporates both the fast and slow chloramine decay pathways. The significance of estimated fast and slow decay rate constants as the kinetic parameters of the model for three water sources in Australia was discussed. It was found that with the same water source, the kinetic parameters remain the same. This modelling approach has the potential to be used by water treatment operators as a decision support tool in order to manage chloramine disinfection.  相似文献   
806.
807.
The aim of this study was to assess the trend of hepatitis A virus (HAV) in a coastal zone impacted by a contamination event, providing data for the development of management strategies. A total of 352 samples, including four bivalve mollusc species (Mytilus galloprovincialis, Solen vagina, Venus gallina and Donax trunculus), were taken over a period of 6 months from 27 production areas of the coast and analysis were performed according to ISO/TS 15216-1:2013. HAV presence was detected in 77 samples from 11 production areas and all positive results were related to samples collected in the first 3 months of the surveillance, during which HAV prevalence was 39.9% and values as high as 5096 genome copies/g were detected. A progressive reduction of viral contamination was evident during the first trimester of the monitoring, with prevalence decreasing from 78.8% in the first month, to 37.8% in the second and 3.9% in the third and quantitative levels reduced from an average value of 672 genome copies/g to 255 genome copies/g over a period of 4 weeks (virus half-life: 21.5 days). A regression analysis showed that, during the decreasing phase of the contamination, the data fitted a reciprocal quadratic model (Ra2 = 0.921) and, based on the model, a residual presence of HAV could be estimated after negativization of the production areas. The statistical analysis of the results per shellfish species and per production area showed that there were limited differences in contamination prevalence and levels among diverse bivalve species, while a statistically significant difference was present in quantitative levels of one production area. These data could be useful for the development of both risk assessment models and code of practice for the management of viral contamination in primary production.  相似文献   
808.

Aim

Injuries in adolescence are an important public health problem and a major cause of morbidity and mortality in this age group. This study aimed to determine the behaviour profile associated to risk of injury and the differences between genders, region and ethnic origin.

Methods

A cross-sectional study design of a nationally representative sample of 1581 adolescents of the Portuguese Health Behaviour in School-Aged Children study.

Results

An occurrence of one injury-related event in the previous year was reported by 21.4% of the respondents and 5.9% referred having more than one injury-related event. Boys reported higher frequency of those events when compared to girls, and non-Portuguese subjects referred higher frequency of events. Scoring higher in violence-related behaviour and psychosomatic complaints was associated to higher chances of referring more than one injury-related event.

Conclusion

Gender, social background and behaviour profile are factors that seem to influence the risk of injuries. This information should guide those involved in the planning of injuries prevention programs in youth.  相似文献   
809.
Legislation giving prominence to psychosocial risk factors at work has changed the role of government occupational health and safety (OHS) inspectors in many countries. Yet little is known about how inspectorates have responded to these changes. Between 2003 and 2007 an Australian study was undertaken on OHS standards, entailing detailed documentary analysis, interviews with 36 inspectorate managers and 89 inspectors, and observations made when researchers accompanied inspectors on 120 typical workplace visits. Our study found that general duty provisions in OHS legislation clearly incorporated psychosocial hazards and inspectorates had introduced guidance material, pursued campaigns and increased interventions in this area. However, the regulatory framework remained narrow (focused on bullying/harassment, occupational violence and work stress) and workplace visits revealed psychosocial hazards as a marginal area of inspectorate activity. These findings were reinforced in interviews. While aware of psychosocial hazards inspectors often saw the issue as problematic due to limited training, resourcing constraints, deficiencies in regulation and fears of victimisation amongst workers. In order to address these problems a number of changes are required that recognize the distinctiveness of psychosocial hazards including their ‘invisibility’. Notable here are revisions to regulation (both general duty provisions and specific codes), the development of comprehensive guidance and assessment tools to be used by inspectors, greater use of procedural enforcement, and enhanced inspectorate resourcing and training. There is also a need to recognize complex inter-linkages between psychosocial hazards and the industrial relations context.  相似文献   
810.
Integrated solutions are needed for sustainable management of risks posed by recreational boats to coastal water quality and ecosystems. Fouling organisms roughen vessel hull surfaces, creating friction that slows sailboats and increases fuel consumption by powerboats. Hull fouling control strategies for recreational boats that are stored in the water may include antifouling hull paints, newer alternative hull coatings, periodic in-water hull cleaning, and excluding propagules by surrounding the boat with a slip liner or raising it above water on a lift. Copper discharged to harbor waters from antifouling paints via passive leaching and in-water hull cleaning may elevate dissolved copper levels above government standards. Invasive species carried among boat-hull fouling organisms may be introduced as boats move among coastal areas. Some of these species tolerate copper in antifouling paints and copper-polluted harbor waters. Policy development must consider supply-side capacity, as well as economic and environmental sustainability, in managing these issues. This paper presents a supply-side evaluation useful in developing policies to co-manage water quality and invasive species risks for recreational boats navigating along the coasts of California, the Baja California peninsula and California's Sacramento-San Joaquin Delta. Supply-side perspectives on services, materials, costs, and boat owner behaviors, such as residence and travel patterns, awareness of hull-coating choices and selection of hull coatings, are determined. Analyses include evaluation of risks, risk management capacity and costs, and role of education in risk management. The issues raised are broadly applicable, as they are appearing on research and policy agendas in diverse coastal areas.  相似文献   
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