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291.
P. A. Zadubrovskiy I. V. Zadubrovskaya M. A. Potapov O. F. Potapova V. I. Evsikov 《Russian Journal of Ecology》2016,47(1):82-87
Demographic structure and its seasonal dynamics have been studied in colonies of narrow-skulled voles (Lasiopodomys gregalis Pall.) in Northern Kulunda. Three types of colonies have been distinguished: (I) true colonies (large, complex families), (II) simple families (nuclear or incomplete), and (III) all-male colonies. Changes in their sex, age, and functional composition (based on animal migration activity) during the breeding season have been analyzed. 相似文献
292.
Daniel Q. Tong Nicholas Z. Muller Haidong Kan Robert O. Mendelsohn 《Environment international》2009,35(8):1109-1117
Human exposure to ambient ozone (O3) has been linked to a variety of adverse health effects. The ozone level at a location is contributed by local production, regional transport, and background ozone. This study combines detailed emission inventory, air quality modeling, and census data to investigate the source–receptor relationships between nitrogen oxides (NOx) emissions and population exposure to ambient O3 in 48 states over the continental United States. By removing NOx emissions from each state one at a time, we calculate the change in O3 exposures by examining the difference between the base and the sensitivity simulations. Based on the 49 simulations, we construct state-level and census region-level source–receptor matrices describing the relationships among these states/regions. We find that, for 43 receptor states, cumulative NOx emissions from upwind states contribute more to O3 exposures than the state's own emissions. In-state emissions are responsible for less than 15% of O3 exposures in 90% of U.S. states. A state's NOx emissions can influence 2 to 40 downwind states by at least a 0.1 ppbv change in population-averaged O3 exposure. The results suggest that the U.S. generally needs a regional strategy to effectively reduce O3 exposures. But the current regional emission control program in the U.S. is a cap-and-trade program that assumes the marginal damage of every ton of NOx is equal. In this study, the average O3 exposures caused by one ton of NOx emissions ranges from ? 2.0 to 2.3 ppm-people-hours depending on the state. The actual damage caused by one ton of NOx emissions varies considerably over space. 相似文献
293.
Among all emerging substances in water, pharmaceutical products (PPs) and residues are a lot of concern. These last two years, the number of studies has increased drastically, however much less for water resources and drinking water than for wastewater. This literature review based on recent works, deals with water resources (surface or groundwater), focusing on characteristics, occurrence and fate of numerous PPs studied, and drinking water including water quality. Through this review, it appears that the pharmaceutical risk must be considered even in drinking water where concentrations are very low. Moreover, there is a lack of research for by-products (metabolites and transformation products) characterization, occurrence and fate in all water types and especially in drinking water. 相似文献
294.
M. Reza Ghanbarpour Keith William Hipel 《Environment, Development and Sustainability》2009,11(2):241-253
Environmental disputes arise due to opposing views of various groups about their environmental concerns and their economic
or developmental interests. Development and protection of the environment constitute two main contradictory objectives within
the sustainable development paradigm, which are often in conflict. The decision support system, GMCR II, which implements
the graph model for conflict resolution, is employed to model and analyze an environmental dispute arising over the construction
of a new freeway between the Iranian capital, Tehran, and the city of Chalous located in the north of the country. This study
demonstrates that the graph model for conflict resolution can be used as a methodology to promote a reasonable balance between
economic development and environmental protection from a strategic viewpoint. In addition to systematically modelling the
conflict by putting the existing information into proper perspective, it is shown how conflict analysis can be used for comparing
alternative scenarios and predicting possible future outcomes.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
295.
William S. Cain Roland Schmidt 《Atmospheric environment (Oxford, England : 1994)》2009,43(16):2591-2601
The US EPA has exempted t-butyl acetate from VOC regulations, which increases the likelihood that it may replace other solvents in some settings. This investigation probes its chemosensory properties. In Study 1, subjects (n = 29) sought to detect the odor of t-butyl acetate and of n-butyl acetate in forced-choice testing of stable concentrations, analytically confirmed. Subjects sniffed from cones with a high enough volumetric flow to insure against dilution by nonodorized air. A subject made hundreds of judgments, enough for a psychometric function for each material. The points of 50% detection above chance (“threshold”) occurred at 8 and 2 ppb for t-butyl acetate and n-butyl acetate, respectively. In study 2, subjects (n = 26) sought to detect vapor with the eye via chemesthesis (sensory irritation) in 10-s exposures. Detection at 50% occurred at 177 and 113 ppm for t-butyl acetate and n-butyl acetate, respectively, more than 10,000 times above that for odor detection. The protocols produced results of uncommon precision compared to those in often-misleading archival databases. The nose exhibits much higher sensitivity than the databases indicate. The collections rarely exhibit accuracy better than ±1000%. Collection of accurate data for a VOC can ironically bring on stricter regulation for just it, a situation that calls for a strategy to improve the database by collection of new data, importation of better data, and development of quantitative structure–activity modeling. 相似文献
296.
Juan G. Navea Shihe Xu Charles O. Stanier Mark A. Young Vicki H. Grassian 《Atmospheric environment (Oxford, England : 1994)》2009,43(26):4060-4069
We have carried out kinetic studies to characterize the heterogeneous decay of octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5) in the presence of representative mineral dust aerosol in order to obtain a better understanding of the atmospheric fate of these siloxanes. The heterogeneous chemistry of D4 and D5 with various mineral dusts was studied in an environmental aerosol reaction chamber using FTIR absorption spectroscopy to monitor the reaction. The apparent heterogeneous uptake coefficient, γapp, for D4 and D5 with various mineral dusts was measured under dry conditions and as a function of relative humidity (RH). In addition, the effect of initial D4 and D5 concentration on the rate and yield of the reaction was examined. The uptake coefficient, γapp, for D4 and D5 was similar for the most reactive aerosols tested, with kaolinite ≈hematite > silica. Limited uptake onto carbon black and calcite surfaces was observed for either siloxane. Reaction with hematite and kaolinite resulted in multilayer coverages, suggesting extensive polymerization of D4 and D5 on the aerosol surface. 相似文献
297.
Hui Li Fazlay Faruque Worth Williams Mohammad Al-Hamdan Jeffrey Luvall William Crosson Douglas Rickman Ashutosh Limaye 《Atmospheric environment (Oxford, England : 1994)》2009,43(28):4303-4310
Aerosol optical depth (AOD), an indirect estimate of particulate matter using satellite observations, has shown great promise in improving estimates of PM2.5 (particulate matter with aerodynamic diameter less than or equal to 2.5 μm) surface. Currently, few studies have been conducted to explore the optimal way to apply AOD data to improve the model accuracy of PM2.5 in a real-time air quality system. We believe that two major aspects may be worthy of consideration in that area: 1) an approach that integrates satellite measurements with ground measurements in the estimates of pollutants and 2) identification of an optimal temporal scale to calculate the correlation of AOD and ground measurements. This paper is focused on the second aspect, identifying the optimal temporal scale to correlate AOD with PM2.5. Five following different temporal scales were chosen to evaluate their impact on the model performance: 1) within the last 3 days, 2) within the last 10 days, 3) within the last 30 days, 4) within the last 90 days, and 5) the time period with the highest correlation in a year. The model performance is evaluated for its accuracy, bias, and errors based on the following selected statistics: the Mean Bias, the Normalized Mean Bias, the Root Mean Square Error, Normalized Mean Error, and the Index of Agreement. This research shows that the model with the temporal scale: within the last 30 days, displays the best model performance in a southern multi-state area centered in Mississippi using 2004 and 2005 data sets. 相似文献
298.
Susceptibility indexing method for irrigation water management planning: applications to K. Menderes river basin, Turkey 总被引:2,自引:0,他引:2
A susceptibility indexing method was developed based on vulnerability and quality indices. The contamination susceptibility index (SI) at a given location was calculated by taking the product of the vulnerability index (VI) and the quality index (QI): SI = VI × QI. This method incorporates both hydrogeological and hydrochemical data for a comprehensive index mapping. The DRASTIC index methodology was used for the hydrogeological data evaluations. The quality index calculation procedure based on a water quality classification scheme was introduced to evaluate hydrochemical data. The suggested susceptibility indexing method was applied to the Küçük Menderes river basin located in western Turkey. The susceptibility index map shows both hydrogeological and hydrochemical data related to the contamination problem including areas that should be taken into consideration during water management planning. The index map indicates that the most susceptible groundwater is located along the river channel between Kiraz and Tire towns, in the Selçuk area and along the Fertek stream channel to the north of Torbal? town. The results indicate that the incorporation of both hydrogeological and hydrochemical datasets enables more realistic evaluations than those of an individual dataset to estimate the groundwater contamination susceptibility of an aquifer. The numerical procedure applied could be extended further by including other parameters such as retardation, potential contaminant sources, etc. that affect the water quality in a given basin. 相似文献
299.
E. Smith R. Gordon C. Bourque A. Campbell S. Génermont P. Rochette M. Mkhabela 《Journal of environmental management》2009
A need exists to improve the utilization of manure nutrients by minimizing NH3 emissions from land application of manure. Management strategies to reduce NH3 emissions are available; however, few have been validated under Canadian conditions. A well tested and accurate simulation model, however, can help overcome this challenge by determining appropriate management strategies for a given set of field conditions. 相似文献
300.
Sustainability assessment (SA) is a holistic and long-range strategic instrument capable of assisting policy-making in electing,
and deciding upon, future development priorities. The outcomes of an SA process become more relevant and strengthened when
conducted with multi-stakeholder engagement, which provides for multiple dialogues and perspectives. This was the object of
research of the SA team in the context of BioScene (Scenarios for Reconciling Biodiversity Conservation with Declining Agriculture Use in Mountain Areas in Europe), a three-year project (2002–2005) funded by the European Union 5th Framework Program, which aimed to investigate the implications
of agricultural restructuring and decline for biodiversity conservation in the mountain areas of Europe, using three distinct
methodological streams: the ecological, the socio-economic, and the SA approaches. The SA approach drew on the previous two
to assess the importance for biodiversity management of different scenarios of agri-environmental change and rural policy
in six countries (France, Greece, Norway, Slovakia, Switzerland, and the United Kingdom), develop causal chains, include stakeholder
views, and identify potential contributions for, or conflicts with, sustainability. This article tells how SA was used, what
sustainability meant in each study area through different objectives of sustainability considered, discusses the methods used
in SA, and the benefits arising. The SA was conducted by a team independent of any study area, who developed and oversaw the
application of the SA methodology, assisting national teams, and developing a cross-country understanding of the sustainability
of proposed scenarios in the different geographical and social contexts, and their implications for policy-making. Finally,
it reflects on the persistent challenges of interdisciplinary research, compounded by multi-cultural teams, and concludes
on the BioScene’s lessons for the further development and application of SA.
相似文献
William R. SheateEmail: |