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111.
112.
Iva H?nová Radek Novotný Tomáš Vráblík Bohumír Lomský 《Environmental pollution (Barking, Essex : 1987)》2010,158(7):2393-2401
Malondialdehyde (MDA), a product of lipid peroxidation and biomarker of oxidative stress, is measured over the long term in spruce Picea abies needles under real conditions in three Czech mountain border areas. The trends presented collate the MDA content in spruce needles with ambient ozone, temperature and precipitation as casual, and defoliation as a subsequent factor for the period 1994-2006. We have found the overall decreasing trends in MDA and defoliation. The highest MDA and defoliation are recorded in the Jizerske, the lowest in the Krusne hory Mts. Out of the examined variables the MDA is predicted best by mean temperature in vegetation season, median of O3 concentrations and AOT40; these three variables account for 34% of MDA1 and 36% of MDA2 variability. Our hypothesis that higher ambient O3 exposure results in higher MDA contents in P. abies needles under real conditions has not been approved. 相似文献
113.
Michael J. White Daniel E. Storm Philip Busteed Scott Stoodley Shannon J. Phillips 《Environmental management》2010,45(5):1164-1174
In the United States, many state and federally funded conservation programs are required to quantify the water quality benefits
resulting from their efforts. The objective of this research was to evaluate the impact of conservation practices subsidized
by the Oklahoma Conservation Commission on phosphorus and sediment loads to Lake Wister. Conservation practices designed to
increase vegetative cover in grazed pastures were evaluated using Landsat imagery and the Soil and Water Assessment Tool (SWAT).
Several vegetative indices were derived from Landsat imagery captured before and after the implementation of conservation
practices. Collectively, these indicators provided an estimate of the change in vegetative soil cover attributable to conservation
practices in treated fields. Field characteristics, management, and changes in vegetative cover were used in the SWAT model
to simulate sediment and phosphorus losses before and after practice implementation. Overall, these conservation practices
yielded a 1.9% improvement in vegetative cover and a predicted sediment load reduction of 3.5%. Changes in phosphorus load
ranged from a 1.0% improvement to a 3.5% increase, depending upon initial vegetative conditions. The use of fertilizers containing
phosphorus as a conservation practice in low-productivity pastures was predicted by SWAT to increase net phosphorus losses
despite any improvement in vegetative cover. This combination of vegetative cover analysis and hydrologic simulation was a
useful tool for evaluating the effects of conservation practices at the basin scale and may provide guidance for the selection
of conservation measures subsidized in future conservation programs. 相似文献
114.
115.
Pietro A. Catizone Steven E. Zell Christopher R. Arrington Michael B. Newman Steven F. Weber Robert J. White 《Journal of the Air & Waste Management Association (1995)》2014,64(3):291-308
Detailed hourly precipitation data are required for long-range modeling of dispersion and wet deposition of particulate matter and water-soluble pollutants using the CALPUFF model. In sparsely populated areas such as the north central United States, ground-based precipitation measurement stations may be too widely spaced to offer a complete and accurate spatial representation of hourly precipitation within a modeling domain. The availability of remotely sensed precipitation data by satellite and the National Weather Service array of next-generation radars (NEXRAD) deployed nationally provide an opportunity to improve on the paucity of data for these areas. Before adopting a new method of precipitation estimation in a modeling protocol, it should be compared with the ground-based precipitation measurements, which are currently relied upon for modeling purposes. This paper presents a statistical comparison between hourly precipitation measurements for the years 2006 through 2008 at 25 ground-based stations in the north central United States and radar-based precipitation measurements available from the National Center for Environmental Predictions (NCEP) as Stage IV data at the nearest grid cell to each selected precipitation station. It was found that the statistical agreement between the two methods depends strongly on whether the ground-based hourly precipitation is measured to within 0.1 in/hr or to within 0.01 in/hr. The results of the statistical comparison indicate that it would be more accurate to use gridded Stage IV precipitation data in a gridded dispersion model for a long-range simulation, than to rely on precipitation data interpolated between widely scattered rain gauges.
Implications:
The current reliance on ground-based rain gauges for precipitation events and hourly data for modeling of dispersion and wet deposition of particulate matter and water-soluble pollutants results in potentially large discontinuity in data coverage and the need to extrapolate data between monitoring stations. The use of radar-based precipitation data, which is available for the entire continental United States and nearby areas, would resolve these data gaps and provide a complete and accurate spatial representation of hourly precipitation within a large modeling domain. 相似文献
116.
Kishor Atreya Fred H?kon Johnsen Bishal Kumar Sitaula 《Environment, Development and Sustainability》2012,14(4):477-493
There is a growing concern of pesticide risks to human health, natural environment and ecosystems. Many previous economic valuations have accounted health aspects or environmental components, but rarely combined; thus, overall risk assessment is partially distorted. The study, conducted close to the capital of Nepal, addressed the health effects of pesticides on small-scale farmers and evaluated the monetary risks of pesticide use on human health and environmental resources. We also aim to establish the relationships among valuation methods. The paper adopts cost of illness, defensive expenditure and contingent valuation willingness to pay approach. The study concluded that the methods used for valuing pesticide risks to human and environmental health are theoretically consistent. The exposed individuals are likely to bear significant economic costs of exposures depending on geographical location, pesticide use magnitudes and frequency. Individuals are willing to pay between 53 and 79% more than the existing pesticide price to protect their health and environment. The integrated pest management training is less likely to reduce health costs of pesticide exposure, although it leads to higher investment in safety measures. 相似文献
117.
In industrialized countries, the idea of degrowth has emerged as a response to environmental, social, and economic crises.
Realizing environmental limits to and failures of more than half a century of continual economic growth in terms of social
progress and environmental sustainability, the degrowth paradigm calls for a downscaling of consumption and production for
social equity and ecological sustainability. The call for economic degrowth is generally considered to be delimited to rich
countries, where reduced consumption can save “ecological space” enabling people in poor countries to enjoy the benefits of
economic growth. China, as one of the economically most expanding countries in the world, has dramatically improved its living
standards, particularly along the Eastern coast, over the latest 30 years. However, China is absent from the international
debates on growth. This article discusses the implications of the Western degrowth debates for China. Given the distinctive
features of China’s development, the paper aims to enrich the degrowth debates, which have hitherto been dominated by Western
perspectives. Based upon reflections on social, environmental, and moral dimensions of economic growth, the paper argues that
limited natural resources may not continuously support universal affluence at the current level of the rich countries, a level
that China is likely to reach within a few decades. Priority for growth in China should therefore be given to the poor regions
of the country, and future growth should be beneficial to social and environmental development. 相似文献
118.
Bruce A. Tichenor Leslie A. Sparks James B. White Merrill D. Jackson 《Journal of the Air & Waste Management Association (1995)》2013,63(4):487-492
Evaluation of Indoor air pollution problems requires an understanding of the relationship between sources, air movement, and outdoor air exchange. Research is underway to investigate these relationships. A three-phase program is being implemented: 1) Environmental chambers are used to provide source emission factors for specific indoor pollutants; 2) An IAQ (Indoor Air Quality) model has been developed to calculate indoor pollutant concentrations based on chamber emissions data and the air exchange and air movement within the indoor environment; and 3) An IAQ test house is used to conduct experiments to evaluate the model results. Examples are provided to show how this coordinated approach can be used to evaluate specific sources of indoor air pollution. Two sources are examined: 1) para-dichlorobenzene emissions from solid moth repellant; and 2) particle emissions from unvented kerosene heaters. The evaluation process for both sources followed the three-phase approach discussed above. Para-dichlorobenzene emission factors were determined by small chamber testing at EPA’s Air and Energy Engineering Research Laboratory. Particle emission factors for the kerosene heaters were developed In large chambers at the J. B. Pierce Foundation Laboratory. Both sources were subsequently evaluated in EPA’s IAQ test house. The IAQ model predictions showed good agreement with the test house measurements when appropriate values were provided for source emissions, outside air exchange, in-house air movement, and deposition on “sink” surfaces. 相似文献
119.
The World Bank used the Consumer Price Index (CPI) to calculate changes in the world poverty level (measured in U.S. dollars)
prior to 1982. In 1983, the U.S. Bureau of Labor Statistics (BLS) replaced the CPI with several indices including CPI-W which
was then adopted by the World Bank. This caused the inflated rate of the U.S. dollars and the percentage of the world population
in poverty to be dramatically underestimated. This new incorrect procedure gives 25% (1.5 million) below the poverty line
in 2005, while the more appropriate procedure (described herein) gives 52% (3.3 million in 2005). The rapid rise of the poverty
line (using the preferable CPI) starting in 1987 occurred at nearly the same time as the peak in per capita annual cereal
production. 相似文献
120.
Pesticide use among smallholder rice farmers in Tanzania 总被引:1,自引:0,他引:1
Nadja Stadlinger Aviti J. Mmochi Sonja Dobo Emma Gyllb?ck Linda Kumblad 《Environment, Development and Sustainability》2011,13(3):641-656
In an interview study conducted among smallholder rice farmers in Rufiji, Tanzania coastal mainland, and in Cheju, Zanzibar, farmer??s pesticide use and risk awareness were assessed. The farmers generally lacked knowledge or possibilities to manage the pesticides as prescribed by the manufacturers. Few farmers knew what kind of pesticides they were using and had never seen the original packages, as pesticides were usually sold per weight or already diluted without labeling. Protective equipment was rarely used since they were not aware of risks associated with pesticides or did not know where to purchase protective gear. Only half of the farmers were aware of pesticides?? health hazards and few associated pesticides with environmental problems. The pesticide use was relatively low, but based on farmers?? pesticide handling and application practices, health risks were a major concern. Most farmers did not believe in successful rice cultivation without using pesticides to control pests. However, estimated yields did not differ between pesticide users or farmers using conventional methods or neem tree extract. To avoid negative effects on human health and the environment, the farmers need basic education and better assistance in their farming practices and pesticide management. 相似文献