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901.
E. Amoozadeh M. Malek R. Rashidinejad S. Nabavi M. Karbassi R. Ghayoumi G. Ghorbanzadeh-Zafarani H. Salehi B. Sures 《Environmental science and pollution research international》2014,21(3):2386-2395
In the present study, cadmium and lead concentrations were compared in barnacles, ghost shrimps, polychaetes, bivalves, and sediment from ten different locations along the intertidal zone of the Persian Gulf and the Gulf of Oman. The results revealed significant differences in the heavy metal concentrations between the organisms with barnacles showing, by far, the highest metal concentrations. The bioaccumulation factor of Cd in different animals follows this pattern with barnacles?>?bivalves?>?polychaetes?>?ghost shrimps, while the pattern for Pb was barnacles?>?polychaetes?>?bivalves?>?ghost shrimps. In most of the stations, sediments showed the lowest lead and cadmium concentrations. Therefore, it is concluded that barnacles with Pb concentrations between 0.17 and 2,016.1 μg/g and Cd concentrations ranging from 0.4 to 147.1 μg/g are the best organisms to be employed in monitoring programs designed to assess pollution with bioavailable metals in the Persian Gulf and the Gulf of Oman. 相似文献
902.
Probabilistic impacts of climate change on flood frequency using response surfaces II: Scotland 总被引:1,自引:0,他引:1
A. L. Kay S. M. Crooks H. N. Davies N. S. Reynard 《Regional Environmental Change》2014,14(3):1243-1255
This paper uses a sensitivity framework approach to look at the probabilistic impacts of climate change on 20-year return period flood peaks, by applying a set of typical response surfaces alongside the probabilistic UK Climate Projections (UKCP09) for 10 river-basin regions over Scotland. The first paper of the pair used the same approach for 10 river-basin regions over England and Wales. This paper develops the methodology for Scotland, by first enabling better estimation of the response type of Scottish catchments. Then, as for England and Wales, the potential range of impacts is shown for different types of catchment in each river-basin region in Scotland, and regional average impact ranges are estimated. Results show clear differences in impacts between catchments of different types and between regions. The Argyll and West Highland regions show the highest impacts, while the North-East Scotland region shows the lowest impacts. The overall ranges are generally smaller for Scotland than England and Wales. 相似文献
903.
904.
905.
P. M. S. Jayathilaka Peeyush Soni Sylvain R. Perret H. P. W. Jayasuriya Vilas M. Salokhe 《Regional Environmental Change》2012,12(1):55-68
Climate change is the main global challenge of this century; it is therefore imperative to identify its effects on agriculture
in developing countries. This research makes spatial assessment of climate change effect on major plantation crops in Sri
Lanka, with emphasis on crop suitability of tea, rubber, and coconut. Geo-referenced maps of spatial and temporal changes
in crop suitability and production potentials are generated and compared. Data pertaining to six agro-ecological zones under
the study area are analyzed for a period of 1980–2007. Crop suitability maps are generated amalgamating yield maps and climatic
factors maps using AHP in multi-criteria analysis under two time frames of 1980–1992 and 1993–2007. Percent change in crop
suitability and crop yield classes is calculated based on five crop suitability and five crop yield classes during two time
frames. Dynamics of climatic parameters and crop yield are recognized using geo-referenced maps. The suitability maps of the
two time frames are compared to identify the changes with each crop in conjunction with changes in the prevailing climate
and yield. Geographic shift of suitability, yield, and climate classes are examined. Net gain or loss in crop production is
quantified. Long-term annual rainfall significantly decreased in mid-country wet zone, whereas the mean temperature of the
study area increased by 1.4°C. Results clearly showed that the climate and yield can be meaningfully related to the crop suitability
and management. 相似文献
906.
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
907.
D. C. Mccune Leonard H. Weinstein Jay S. Jacobson A. E. Hitchcock 《Journal of the Air & Waste Management Association (1995)》2013,63(11):465-468
Leaves of Tendergreen bean plants exposed to atmospheric fluoride concentrations in the range 1.7 to 7.6 μg/m3 showed increased levels of enolase and catalase activity and decreased levels of pyruvate and α-ketoglutarate. Phosphoenolpyruvate carboxylase activity and oxalacetate were not affected. The leaves of Milo maize plants exposed to 5.0 μg F/m3 showed increased levels of enolase and pyruvate kinase activity and a decreased level of pyruvate. Oxalacetate and α-ketoglutarate levels were not affected. Catalase activity was increased, then decreased by IIF fumigation. The changes induced by HF were greatest six to 10 days after the start of fumigation and disappeared or decreased in magnitude during the post-fumigation period. 相似文献
908.
909.
Marvin H. Green 《Journal of the Air & Waste Management Association (1995)》2013,63(12):703-706
First-prize winner in the student paper competition conducted by the Mid-Atlantic States Section of the Air Pollution Control Association was Marvin H. Green, a graduate student at Drexel Institute of Technology and assistant chief of Philadelphia’s Air Pollution Control Section. A condensation of his paper follows. 相似文献
910.
H. C. Wohlers M. Feldstein 《Journal of the Air & Waste Management Association (1995)》2013,63(5):226-229
The problem of an investigation of the need for a regulation on organic compound emissions in the San Francisco Bay Area can be divided into two major areas: 1. Is there a need for a regulation on organic compound emissions? What is the extent of photochemical smog effects? How much control is necessary to achieve the desired effects? 2. (2) If the need exists for an organic compound regulation, can a performance type regulation be written for all types of organic compound emissions? Must the regulation be directed toward specific industries or types of emissions? Can the regulation be adequately enforced—both practically and legally? This paper will describe the studies undertaken by the District Staff to answer the first set of questions. Work covering the second group of questions is now under investigation. 相似文献