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311.
An Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopic method was used to measure organic functional groups and inorganic ions at Tonto National Monument (TNM), an Interagency Monitoring of Protected Visual Environments (IMPROVE) sampling site in a rural area near Phoenix, Arizona. Functional groups and ions from common aerosol compound classes such as aliphatic and aromatic CH, methylene, methyl, aldehydes/ketones, carboxylic acids, ammonium sulfate and nitrate as well as functional groups from difficult to measure compound classes such as esters/lactones, acid anhydrides, carbohydrate hydroxyl and ethers, amino acids, and amines were quantified. On average, ~33% of the PM1.0 mass was composed of organic aerosol. The average (standard deviation) composition of the organic aerosol at TNM was 34% (6%) biogenic functional groups, 21% (5%) oxygenated functional groups, 28% (7%) aliphatic hydrocarbon functional groups (aliphatic CH, methylene and methyl) and 17% (1%) aromatic hydrocarbon functional groups. Compositional analysis, functional group correlations, and back trajectories were used to identify three types of events with source signatures: primary biogenic-influenced, urban-influenced, and regional background. The biogenic-influenced event had high concentrations of amino acids and carbohydrate hydroxyl and ether, as well as aliphatic CH and aromatic CH functional groups and qualitatively high levels of silicate. The urban-influenced events had back trajectories traveling directly from the Phoenix area and high concentrations of hydrocarbons, oxygenated functional groups, and inorganic ions. This aerosol characterization suggests that both primary emissions in Phoenix and secondary formation of aerosols from Phoenix emissions had a major impact on the aerosol composition and concentration at TNM. The regional background source had low concentrations of all functional groups, but had higher concentrations of biogenic functional groups than the urban source.  相似文献   
312.
The impact of the number of displayed credentials (0, 2, 4, or 9) and the presence or absence of family photographs on participants' judgments of a therapist's qualities was assessed. In a between-participants design, 227 participants made these judgments after viewing a projected digital image of a therapist's office. The judgments of the characteristics yielded three factors, Qualifications, Friendliness, and Energy. Analyses indicated that in general, the greater the number of credentials, the more positive the judgment of the therapist's Qualifications and Energy. The presence of family pictures had no significant impact on judgments. Results are discussed in terms of recommendations for the counseling environment.  相似文献   
313.
Although humans are a major mechanism for short and long distance seed dispersal, there is limited research testing clothing as a vector. The effect of different types of material (sports vs hiking socks), or different items of clothing (boots, socks, laces vs legs) or the same item (socks) worn in different places on seed composition were assessed in Kosciuszko National Park, Australia. Data was analyzed using Repeated Measures ANOVA, independent and paired t-tests, Multi-dimensional Scaling Ordinations and Analysis of Similarity. A total of 24,776 seeds from 70 taxa were collected from the 207 pieces of clothing sampled, with seed identified from 31 native and 19 non-native species. Socks worn off-track collected more native seeds while those worn on roadsides collected more non-native seeds. Sports socks collected a greater diversity of seeds and more native seeds than hiking socks. Boots, uncovered socks and laces collect more seeds than covered socks and laces, resulting in 17% fewer seeds collected when wearing trousers. With seeds from over 179 species (134 recognized weeds) collected on clothing in this, and nine other studies, it is clear that clothing contributes to unintended human mediated seed dispersal, including for many invasive species.  相似文献   
314.
Stream habitat assessments are conducted to evaluate biological potential, determine anthropogenic impacts, and guide restoration projects. Utilizing these procedures, managers must first select a representative stream reach, which is typically selected based on several criteria. To develop a consistent and unbiased procedure for choosing sampling locations, the Illinois Department of Natural Resources and the Illinois Natural History Survey have proposed a technique by which watersheds are divided into homogeneous stream segments called valley segments. Valley segments are determined by GIS parameters including surficial geology, predicted flow, slope, and drainage area. To date, no research has been conducted to determine if the stream habitat within a valley segment is homogeneous and if different valley segments have varying habitat variables. Two abutting valley segments were randomly selected within 13 streams in the Embarras River watershed, located in east-central Illinois. One hundred meter reaches were randomly selected within each valley segment, and a transect method was used to quantify habitat characteristics of the stream channel. Habitat variables for each stream were combined through a principal components analysis (PCA) to measure environmental variation between abutting valley segments. A multivariate analysis of variance (MANOVA) was performed on PCA axes 1–3. The majority of abutting valley segments were significantly different from each other indicating that habitat variability within each valley segment was less than variability between valley segments (5.37 ≤ F ≤ 245.13; P ≤ 0.002). This comparison supports the use of the valley segment model as an effective management tool for identifying representative sampling locations and extrapolating reach-specific information.  相似文献   
315.
Volatile aldehydes are produced during degradation of paper-based materials. This may result in their accumulation in archival and library repositories. However, no systematic study has been performed so far. In the frame of this study, passive sampling was carried out at ten locations in four libraries and archives. Despite the very variable sampling locations, no major differences were found, although air-filtered repositories were found to have lower concentrations while a non-ventilated newspaper repository exhibited the highest concentrations of volatile aldehydes (formaldehyde, acetaldehyde, furfural and hexanal). Five employees in one institution were also provided with personal passive samplers to investigate employees’ exposure to volatile aldehydes. All values were lower than the presently valid exposure limits.The concentration of volatile aldehydes, acetic acid, and volatile organic compounds (VOCs) in general was also compared with that of outdoor-generated pollutants. It was evident that inside the repository and particularly inside archival boxes, the concentration of VOCs and acetic acid was much higher than the concentration of outdoor-generated pollutants, which are otherwise more routinely studied in connection with heritage materials. This indicates that further work on the pro-degradative effect of VOCs on heritage materials is necessary and that monitoring of VOCs in heritage institutions should become more widespread.  相似文献   
316.
Sewage sludge and yard waste compost were used as biofilter materials and tested with respect to their capacity for removing ammonia from air at different water contents. Ammonia removal was measured in biofilters containing compost wetted to different moisture contents ranging from air dry to field capacity (maximum water holding capacity). Filters were operated for 15 days and subsequently analyzed for NH3/NH4+, NO2-, and NO3-. The measured nitrogen species concentration profiles inside the filters were used to calculate ammonia removal rates. The results showed that ammonia removal is strongly dependent on the water content in the filter material. At gravimetric water contents below 0.25 g H2O g solids(-1) for the yard waste compost and 0.5 g H2O g solids(-1) ammonia removal rates were very low but increased rapidly above these values. The sewage sludge compost filters yielded more than twice the ammonia removal rate observed for yard waste compost likely because of a high initial concentration of nitrifying bacteria originating from the wastewater treatment process and a high airwater interphase surface area that facilitates effective ammonia dissolution and transport to the biofilm.  相似文献   
317.
Benthic infauna were sampled from 251 Southern California Bight (SCB) mainland shelf sites in the summer of 1994. Sample sites were selected using a stratified random design, with the primary strata being depth zone, geography, and proximity to point and non-point discharges. Benthic infaunal condition was assessed using the Benthic Response Index (BRI), and by comparing dominant taxa and community parameters (e.g., number of taxa) among strata. Ninety-one percent of sediments in the SCB were found to contain healthy benthic communities. Most stations with altered benthos were located near river mouths, in Santa Monica Bay, or on the Palos Verdes Shelf. Deviations at sites with altered benthic communities were mostly limited to minor changes in species composition, rather than to large declines in diversity or abundance.  相似文献   
318.

The relationship between wealth and climate change concern has been a focus of several studies. In this article, we hypothesize that richer households (and countries) are less concerned about climate change because wealth provides a buffer against some of the related risks. This leads people in wealthier countries and households to perceive a greater sense of control over climate change impacts, which in turn results in lower levels of concern. We tested this hypothesis using a unique household survey encompassing 11 OECD countries and over 10,000 households and applying mixed multi-level regression models. Our results confirmed a statistically significant negative relationship between country and household wealth and individuals’ perceptions of the seriousness of climate change. This study contributes to current literature by showing that this relationship is mediated through sense of control, measured at the country level by the country’s readiness index and at the individual household level by the extent of adoption of energy efficiency improvements. These findings raise the question of how best to incentivize action on climate change amongst those with the ability—but not necessarily the motivation—to respond.

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319.
保护生态系统服务功能越来越多地被作为风险评估的目标,但是目前生态风险评估的终点和评估生态系统服务功能受到的潜在影响之间有很大的差距。作者提出了一个框架,将常用的生态毒理学终点与对种群和群落的影响以及生态系统的服务功能联系起来。这个框架建立在机制效应模型的长足进步上,这些模型旨在跨越多种生物组织,并解释各种生物相互作用和反馈。为了说明这一点,作者引入了2个研究案例,它们采用了已完善和已验证的机制效应模型:鱼种群的inSTREAM个体模型和AQUATOX生态系统模型。他们还展示了动态能量平衡理论可以为解释组织级毒性提供一种通用货币。他们认为,一个基于机制模型的框架,可以预测化学品暴露对生态系统服务的影响,再结合经济估值,可以为环境管理提供一种有用的方法。作者强调了使用这个框架的潜在好处以及未来工作中需要解决的挑战。
精选自Forbes, V. E., Salice, C. J., Birnir, B., Bruins, R. J.F., Calow, P., Ducrot, V., Galic, N., Garber, K., Harvey, B. C., Jager, H., Kanarek, A., Pastorok, R., Railsback, S. F., Rebarber, R. and Thorbek, P. (2017), A framework for predicting impacts on ecosystem services from (sub)organismal responses to chemicals. Environmental Toxicology and Chemistry, 36: 845–859. doi: 10.1002/etc.3720
详情请见http://onlinelibrary.wiley.com/doi/10.1002/etc.3720/full
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320.
The capacity to sustainably govern complex socio-ecological systems (SES) has been identified as a necessary but daunting task by SES scholars, resource stewards and stakeholders. This research sought to inform the question: What are determinant capacities and functional linkages that can be incorporated into diagnostic tools for analysts seeking to improve sustainable socio-economic system SES governance? Literature was used to identify and translate determinant capacities and functional linkages into a quantifiable metric of governance quality. The tool was developed from ecological, business, governance and decision science literature. This tool recognizes the dynamic and systemic linkages between the resources and the social systems that use and govern them for improving systems thinking and SES outcomes. The tool was tested to determine its ability to capture perceived characteristics of governance quality and problem management using Michigan’s cleanup and redevelopment program. The results of this research indicated that the exploratory tool was reliable and valid. This research contributes to the evolving body of SES frameworks, specifically the study of individual and organizational capacities for improved SES outcomes. The implications of this research suggest participatory network-based governance with higher levels of resource exchange, in the form of interdependency, trust, diplomacy and reciprocity, aligns with practitioners’ perceptions of improved program performance. Further, while some capacities and related findings of this research may be context specific, concepts associated with the development and testing of this diagnostic tool, such as the use of systems thinking, participatory network-based governance, and related competencies, may have more universal application.  相似文献   
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