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51.
Abstract: We examined the relationship between authorship and the use of biological information in recovery plans under the U.S. Endangered Species Act. Approximately one-third of recovery plans were written solely by federal government employees, and one-third of plans included authors with university affiliations. The number of plans written strictly by federal staff increased significantly over time, whereas the percentage of plans that included authors with university affiliation remained unchanged. We tested three hypotheses posed by Clark et al. (1994) regarding authorship and endangered species recovery and found that (1) groups of authors from diverse affiliations are likely to strengthen the recovery planning process, (2) recovery plans lacking nonfederal participation suffer from inadequate attention to species biology, and (3) academic affiliation is strongly associated with the use of focal-species biology in recovery plans. Our results suggest that modifying the choice of participants in the recovery planning process may increase the use of biological information in recovery measures recommended in recovery plans and thus influence the eventual success of recovery efforts.  相似文献   
52.
Tropical soils are important sources and sinks of atmospheric methane (CH4) and major sources of oxides of nitrogen gases, nitrous oxide (NM2O) and NOx (NO+NO2). These gases are present in the atmosphere in trace amounts and are important to atmospheric chemistry and earth's radiative balance. Although nitric oxide (NO) does not directly contribute to the greenhouse effect by absorbing infrared radiation, it contributes to climate forcing through its role in photochemistry of hydroxyl radicals and ozone (O3) and plays a key role in air quality issues. Agricultural soils are a primary source of anthropogenic trace gas emissions, and the tropics and subtropics contribute greatly, particularly since 51% of world soils are in these climate zones. The soil microbial processes responsible for the production and consumption of CH4 and production of N-oxides are the same in all parts of the globe, regardless of climate. Because of the ubiquitous nature of the basic enzymatic processes in the soil, the biological processes responsible for the production of NO, N2O and CH4, nitrification/denitrification and methanogenesis/methanotropy are discussed in general terms. Soil water content and nutrient availability are key controls for production, consumption and emission of these gases. Intensive studies of CH4 exchange in rice production systems made during the past decade reveal new insight. At the same time, there have been relatively few measurements of CH4, N2O or NOx fluxes in upland tropical crop production systems. There are even fewer studies in which simultaneous measurements of these gases are reported. Such measurements are necessary for determining total greenhouse gas emission budgets. While intensive agricultural systems are important global sources of N2O and CH4 recent studies are revealing that the impact of tropical land use change on trace gas emissions is not as great as first reports suggested. It is becoming apparent that although conversion of forests to grazing lands initially induces higher N-oxide emissions than observed from the primary forest, within a few years emissions of NO and N2O generally fall below those from the primary forest. On the other hand, CH4 oxidation is typically greatly reduced and grazing lands may even become net sources in situations where soil compaction from cattle traffic limits gas diffusion. Establishment of tree-based systems following slash-and-burn agriculture enhances N2O and NO emissions during and immediately following burning. These emissions soon decline to rates similar to those observed in secondary forest while CH4 consumption rates are slightly reduced. Conversion to intensive cropping systems, on the other hand, results in significant increases in N2O emissions, a loss of the CH4 sink, and a substantial increase in the global warming potential compared to the forest and tree-based systems. The increasing intensification of crop production in the tropics, in which N fertilization must increase for many crops to sustain production, will most certainly increase N-oxide emissions. The increase, however, may be on the same order as that expected in temperate crop production, thus smaller than some have predicted. In addition, increased attention to management of fertilizer and water may reduce trace gas emissions and simultaneously increase fertilizer use efficiency.  相似文献   
53.
Little is known about the effectiveness of family‐friendly policies (FFPs) in reducing interrole conflicts involving work and family. The present study examined the influence of FFPs, work‐family culture, and family characteristics on salient job outcomes, and multiple dimensions of work‐family conflict (WFC) and family‐work conflict (FWC). Results from a survey of 564 workers, indicate that FFPs exert minimal effects on felt conflict, and that a positive work‐family culture and family support may be more instrumental in helping employees balance work and home roles. Findings also suggest that sources of conflict varied among workers, as did the mechanisms used to address WFC and FWC. This study underscores the importance of examining WFC as a multi‐dimensional phenomenon affecting employees in a variety of family structures, as well as considering the impact of FFPs in conjunction with work‐family culture. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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This paper presents a composite methodology for obtaining spatial and temporal projections of charging demand and peak-shaving potential from plug-in electric vehicles (EVs), and the associated spatio-temporal impacts on peak household electrical load. The methodology comprises a suite of models of future EV uptake, travel by households, household electricity demand and recharge/discharge of EVs at their home locations. The analysis is disaggregated to hourly time-steps over a full year, and spatially to mesh blocks comprising around 250 houses per block. The modelling suite is applied to an analysis of peak household load impacts across the state of Victoria, Australia, under nine different combinations of EV uptake and charging/discharging behaviour. The projected increase in peak household electrical loads under expected penetration rates and charging demands is less than 10 % on most high-demand days, but can be up to 15 % on a handful of days and geographic locations. Peak-load impacts under off-peak charging are mostly less than 5 %. With judicious EV discharging strategies, there is potential to shave peak loads on the highest demand days by up to 5 %.  相似文献   
57.
Electricity network investment and asset management require accurate estimation of future demand in energy consumption within specified service areas. For this purpose, simple models are typically developed to predict future trends in electricity consumption using various methods and assumptions. This paper presents a statistical model to predict electricity consumption in the residential sector at the Census Collection District (CCD) level over the state of New South Wales, Australia, based on spatial building and household characteristics. Residential household demographic and building data from the Australian Bureau of Statistics (ABS) and actual electricity consumption data from electricity companies are merged for 74 % of the 12,000 CCDs in the state. Eighty percent of the merged dataset is randomly set aside to establish the model using regression analysis, and the remaining 20 % is used to independently test the accuracy of model prediction against actual consumption. In 90 % of the cases, the predicted consumption is shown to be within 5 kWh per dwelling per day from actual values, with an overall state accuracy of ?1.15 %. Given a future scenario with a shift in climate zone and a growth in population, the model is used to identify the geographical or service areas that are most likely to have increased electricity consumption. Such geographical representation can be of great benefit when assessing alternatives to the centralised generation of energy; having such a model gives a quantifiable method to selecting the ‘most’ appropriate system when a review or upgrade of the network infrastructure is required.  相似文献   
58.
ABSTRACT

The essay uses the term “charismatic life” to describe representations of nature that emphasize vitality and vibrancy. Beginning with how life is reified when nature becomes spectacle, the essay discusses how a fetishism of life was part of the early structuring logic of biodiversity science in a way that undermined crafting other ethical and political responses to loss. When biodiversity emerged as a popular science concept in the 1980s, it was described as a scientific replacement for the sentimental attachment to charismatic megafauna that previously structured conservation priorities. But this essay argues, in a historicized reading of conservation biologist E.O. Wilson’s popular science memoir Biophilia [Wilson, E. O. (1984). Biophilia. Cambridge: Harvard University Press] alongside the seminal edited collection Biodiversity [Wilson, E. O. (Ed.). (1988). Biodiversity. Washington, DC: National Academy of Sciences], that Wilson’s sentimental biopolitics renders the world as if a collection of living souvenirs – tokens by which to remember forms of life that will have been lost.  相似文献   
59.
This study was conducted to derive receptor-specific outdoor exposure concentrations of total suspended particulate (TSP) and respirable (dae ≤ 10 µm) air manganese (air-Mn) for East Liverpool and Marietta (Ohio) in the absence of facility emissions data, but where long-term air measurements were available. Our “site-surface area emissions method” used U.S. Environmental Protection Agency’s (EPA) AERMOD (AMS/EPA Regulatory Model) dispersion model and air measurement data to estimate concentrations for residential receptor sites in the two communities. Modeled concentrations were used to create ratios between receptor points and calibrated using measured data from local air monitoring stations. Estimated outdoor air-Mn concentrations were derived for individual study subjects in both towns. The mean estimated long-term air-Mn exposure levels for total suspended particulate were 0.35 μg/m3 (geometric mean [GM]) and 0.88 μg/m3 (arithmetic mean [AM]) in East Liverpool (range: 0.014–6.32 μg/m3) and 0.17 μg/m3 (GM) and 0.21 μg/m3 (AM) in Marietta (range: 0.03–1.61 μg/m3). Modeled results compared well with averaged ambient air measurements from local air monitoring stations. Exposure to respirable Mn particulate matter (PM10; PM <10 μm) was higher in Marietta residents.

Implications: Few available studies evaluate long-term health outcomes from inhalational manganese (Mn) exposure in residential populations, due in part to challenges in measuring individual exposures. Local long-term air measurements provide the means to calibrate models used in estimating long-term exposures. Furthermore, this combination of modeling and ambient air sampling can be used to derive receptor-specific exposure estimates even in the absence of source emissions data for use in human health outcome studies.  相似文献   
60.
Environmental impact assessment (EIA) has been promoted as an instrument for preventive environmental management in construction projects, but its performance in safeguarding the environment through influencing project decision-making is questioned. This paper probes the underlying reasons from a governance perspective as an important supplement to the regulatory and technical perspectives. A framework, with process integration, professional governance, and public engagement being its key components, is proposed to analyze the governance arrangements that enable or inhibit the effective functioning of EIA, based on which a comparative study of three infrastructure projects in China, the United States and Finland was conducted. The results reveal that, while the level of process integration and public engagement of EIA determines the degree to which EIA influences project decisions, it is the professional governance that controls the accountability of EIA. The paper has implications on institutionally where efforts should be directed to improve the performance of EIA.  相似文献   
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