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141.
This paper addresses a measurement of corporate environmental performance, and its application to the analysis of efficiency in the petroleum firms. In order to measure firms' environmental performance, we suggest a framework called “Gscore” that consists of five categories, namely general environmental management (GEM), input, process, output, and outcome. Gscore is a proxy measure of corporate environmental performance based on voluntary environment, health, and safety (EHS) report and is calculated by aggregating the points of the above five-categories. We apply our measurement framework to the data of 39 firms' voluntary EHS reports which are available on the internet. Ten of them, on which efficiency analysis was conducted with Gscore, assets, employee, and profits, are in petroleum and refining industry. According to our results: (1) a gap is found between rhetoric and practical environmental management stemming from calculating the relation between GEM and data part in 39 EHS reports. (2) On the whole, EHS reports of petroleum firms have something in common, but there are significant differences in the type and amounts of disclosed data among the EHS reports. (3) From the results of efficiency analysis, it is found that the number of employee exerts a considerable influence on determining the relative efficiency of petroleum firms, then Gscore, profits, and assets in sequence. Furthermore, Exxon, Ashland, Phillips Petroleum, and ARCO are shown to be efficient among 10 petroleum firms. 相似文献
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144.
Estimating erosion in a riverine watershed bayou liberty-tchefuncta river in louisiana 总被引:1,自引:0,他引:1
Martin A Gunter JT Regens JL 《Environmental science and pollution research international》2003,10(4):245-250
GOAL, SCOPE, BACKGROUND: Sheet erosion from agricultural, forest and urban lands may increase stream sediment loads as well as transport other pollutants that adversely affect water quality, reduce agricultural and forest production, and increase infrastructure maintenance costs. This study uses spatial analysis techniques and a numerical modeling approach to predict areas with the greatest sheet erosion potential given different soils disturbance scenarios. METHODS: A Geographic Information System (GIS) and the Universal Soil Loss Equation (USLE) were used to estimate sheet erosion from 0.64 ha parcels of land within the watershed. The Soil Survey of St. Tammany Parish, Louisiana was digitized, required soil attributes entered into the GIS database, and slope factors determined for each 80 x 80 meter parcel in the watershed. The GIS/USLE model used series-specific erosion K factors, a rainfall factor of 89, and a GIS database of scenario-driven cropping and erosion control practice factors to estimate potential soil loss due to sheet erosion. RESULTS AND DISCUSSION: A general trend of increased potential sheet erosion occurred for all land use categories (urban, agriculture/grasslands, forests) as soil disturbance increases from cropping, logging and construction activities. Modeling indicated that rapidly growing urban areas have the greatest potential for sheet erosion. Evergreen and mixed forests (production forest) had lower sheet erosion potentials; with deciduous forests (mostly riparian) having the least sheet erosion potential. Erosion estimates from construction activities may be overestimated because of the value chosen for the erosion control practice factor. CONCLUSIONS: This study illustrates the ease with which GIS can be integrated with the Universal Soil Loss Equation to identify areas with high sheet erosion potential for large scale management and policy decision making. RECOMMENDATIONS: The GIS/USLE modeling approach used in this study offers a quick and inexpensive tool for estimating sheet erosion within watersheds using publicly available information. This method can quickly identify discrete locations with relatively precise spatial boundaries (approximately 80 meter resolution) that have a high sheet erosion potential as well as areas where management interventions might be appropriate to prevent or ameliorate erosion. 相似文献
145.
H. Jung 《Die Naturwissenschaften》1942,30(17-18):266-267
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147.
Soon-Ho Choi Young Sung Ghim Young-Soo Chang Kweon Jung 《Environmental science and pollution research international》2014,21(9):5972-5982
The behavior of particulate matter (PM) during high-concentration episodes was investigated using monitoring data from Guui station, a comprehensive air monitoring station in Seoul, Korea, from January 2008 to March 2010. Five non-Asian dust (ND) episodes and two Asian dust (AD) episodes of high PM concentrations were selected for the study. During the ND episode, primary air pollutants accumulated due to low wind speeds, and PM2.5 increased along with most other air pollutants. Particles larger than PM2.5 were also high since these particles were generated by vehicular traffic rather than wind erosion. During strong AD episodes, PM10–2.5 primarily increased and gaseous primary air pollutants decreased under high wind speeds. However, even during the AD episode, PM2.5 and gaseous primary air pollutants increased when the effects of AD were weak and wind speeds were low. This study corroborates that accumulation of air pollutants due to a drop in surface wind speed plays an important role in short-term high-concentration occurrences. However, low wind speeds could not be directly linked to local emissions because a significant portion of accumulated air pollutants resulted from long-range transport. 相似文献
148.
Kerstin Hartsch Andreas Weller Silvia Rosas Gunter Reppchen 《Die Naturwissenschaften》2009,96(10):1213-1220
The Nasca geoglyphs in the stone desert in southern Peru are part of our world cultural heritage. These remarkable drawings have roused the interest of scientists from different disciplines. Here we report the results of integrated geophysical, petrophysical, mineralogical, and geochemical investigations of the geoglyphs at six test sites in the stone desert around Nasca and Palpa. The geomagnetic measurements revealed clear indications of subsurface structures that differ from the visible surface geoglyphs. The high-resolution geoelectrical images show unexpected resistivity anomalies underneath the geoglyphs down to a depth of about 2 m. Remarkable structures were revealed in both vertical and lateral directions. No evidence was found of geochemical or mineralogical alterations of the natural geogenic materials (desert pavement environment versus geoglyphs). Neither salts nor other mineral materials were used by the Nasca people to alter or prepare the surfaces of geoglyphs. This supports the hypothesis that the Nasca people simply removed stone material down to the natural hard pan horizon to create the geoglyphs. 相似文献
149.
Mercury contamination in agricultural soils from abandoned metal mines classified by geology and mineralization 总被引:1,自引:0,他引:1
The concentrations and loadings of major and trace elements in coal mine drainage (CMD) from 49 abandoned mines located in
the coal fields of the Brazilian state of Santa Catarina were determined. The CMD sites typically displayed a wide spatial
and temporal variability in physical and geochemical conditions. The results of our CMD analyses in Santa Catarina State were
used to illustrate that the geochemical processes in the rock piles can be deduced from multiple data sets. The observed relationship
between the pH and constituent concentrations were attributed to (1) dilution of acidic water by near-neutral or alkaline
groundwater and (2) solubility control of Al, Fe, Mn, Ba and Sr by hydroxide, sulfate, and/or carbonate minerals. The preliminary
results of the CMD analyses and environmental health in the Santa Catarina region, Brazil, are discussed. 相似文献
150.
Tae-In Ohm Jong-Seung Chae Seung-Hyun Moon Bong-Jin Jung 《Process Safety and Environmental Protection》2013,91(3):227-234
Swine excreta were dried by boiling via immersion in hot oil. In this method, moisture in the excreta is replaced with oil or evaporated by turbulent heat transfer in high-temperature oil. The dried excreta can be used in an incinerator like low-rank coal or solid fuel. Refined waste oil and B–C heavy oil were used for drying. Drying for 8 min at 150 °C reduced the water content of raw excreta from 78.90 wt.% to 1.56 wt.% (refined waste oil) or 1.62 wt.% (B–C heavy oil) and that of digested excreta from 79.58 wt.% to 3.40 wt.% (refined waste oil) or 3.48 wt.% (B–C heavy oil). The low heating values of the raw and digested excreta were 422 kJ/kg and ?2,713 kJ/kg, respectively, before drying and 27,842–28,169 kJ/kg and 14,394–14,905 kJ/kg, respectively, after drying. A heavy metal analysis did not detect Hg, Pb, Cd, As, and Cr in the dried excreta, but Al, Cu, and Zn, which occur in the feed formula, were detected. Thermogravimetric analysis before and after drying revealed that emission of volatiles and combustion of volatiles and fixed carbon occurred at temperatures of 250–500 °C when air was used as the transfer gas. 相似文献