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101.
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   
102.
103.
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   
104.
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   
105.
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   
106.
Pesticide use among smallholder rice farmers in Tanzania   总被引:1,自引:0,他引:1  
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   
107.
This study concerns measurements of radon and thoron emissions from soil carried out in 2004 on the eastern flank of Mt. Etna, in a zone characterized by the presence of numerous seismogenic and aseismic faults. The statistical treatment of the geochemical data allowed recognizing anomaly thresholds for both parameters and producing distribution maps that highlighted a significant spatial correlation between soil gas anomalies and tectonic lineaments. The seismic activity occurring in and around the study area during 2004 was analyzed, producing maps of hypocentral depth and released seismic energy. Both radon and thoron anomalies were located in areas affected by relatively deep (5-10 km depth) seismic activity, while less evident correlation was found between soil gas anomalies and the released seismic energy. This study confirms that mapping the distribution of radon and thoron in soil gas can reveal hidden faults buried by recent soil cover or faults that are not clearly visible at the surface. The correlation between soil gas data and earthquakes depth and intensity can give some hints on the source of gas and/or on fault dynamics.  相似文献   
108.
This investigation was under taken to evaluate the groundwater resources contamination due to intensive agricultural practices (particularly greenhouses). The study-area is located in the coastal area of the Ragusa province (South-East Sicily), where numerous existing greenhouses may cause the contamination of groundwater systems (unconfined and confined aquifers) beneath the cropped land. The pollution risk is mainly related with the seepage process of macro-elements nitrogen (N), phosphorus (P), potassium (K), held in the irrigation water and the massive use of fertilizers and pesticides, that may pass through the unsaturated zone of the soil profile. Moreover, the area is characterized by the presence of several wells (about 15 wells/km2) for agricultural use that cause the aquifer overexploitation and the consequent risk of seawater intrusion. The agriculture practices adopted in the study area (irrigation volumes, fertilizer concentrations, use of pesticides…) were monitored since February 2009; moreover, the pollution risk of the aquifers was evaluated through the analysis of groundwater water samples collected (monthly) in the monitoring wells; in particular, nitrogen compounds, soluble phosphorous (PO?2?), potassium, as well as the main pesticides commonly used in the study area, were measured.The results show that electrical conductivity and chloride concentration values can cause reduction of production and leaf damage problems, respectively, for most of the monitored farm systems. The high nitrogen compounds concentrations observed in the monitored wells can cause health and environmental problems. Moreover high pesticide contamination of groundwater was found in two of the five monitored wells.  相似文献   
109.

Background and purpose  

More and more coal-fired power plants equipped with seawater flue gas desulfurization systems have been built in coastal areas. They release large amount of mercury (Hg)-containing waste seawater into the adjacent seas. However, very limited impact studies have been carried out. Our research targeted the distribution of Hg in the seawater, sediment, biota, and atmosphere, and its environmental transportation.  相似文献   
110.

Purpose

Hexachlorocyclohexane (HCH) isomers (??-, ??- and ??- (Lindane)) were recently included as new persistent organic pollutants (POPs) in the Stockholm Convention, and therefore, the legacy of HCH and Lindane production became a contemporary topic of global relevance. This article wants to briefly summarise the outcomes of the Stockholm Convention process and make an estimation of the amount of HCH waste generated and dumped in the former Lindane/HCH-producing countries.

Results

In a preliminary assessment, the countries and the respective amount of HCH residues stored and deposited from Lindane production are estimated. Between 4 and 7 million tonnes of wastes of toxic, persistent and bioaccumulative residues (largely consisting of alpha- (approx. 80%) and beta-HCH) are estimated to have been produced and discarded around the globe during 60 years of Lindane production. For approximately 1.9 million tonnes, information is available regarding deposition. Countries are: Austria, Brazil, China, Czech Republic, France, Germany, Hungary, India, Italy, Japan, Macedonia, Nigeria, Poland, Romania, Slovakia, South Africa, Spain, Switzerland, Turkey, The Netherlands, UK, USA, and former USSR. The paper highlights the environmental relevance of deposited HCH wastes and the related POPs?? contaminated sites and provides suggestions for further steps to address the challenge of the legacy of HCH/Lindane production.

Conclusion

It can be expected that most locations where HCH waste was discarded/stockpiled are not secured and that critical environmental impacts are resulting from leaching and volatilisation. As parties to the Stockholm Convention are legally required to take action to stop further POPs pollution, identification and evaluation of such sites are necessary.  相似文献   
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