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1.
Aerosol constituents (elemental carbon, organic carbon, soluble ions including organic acids, and selected trace metals) were investigated from samples of a field campaign taking place at Bhola Island in the Bay of Bengal (Bangladesh). The campaign took place in the pre-monsoon season (May 2001) using low volume samplers. Carbonaceous material comprised the majority of the analysed components. The average concentrations of EC and OC were 2.8 and 4.6 microg m(-3), respectively. Oxalic acid was the most abundant dicarboxylic acid (average 268 ng m(-3)) followed by malonic and malic acid. The contribution of carboxylic acids-carbon to organic carbon was 2.0%. Average concentrations observed for sulfate and nitrate were 3.7 microg m(-3) and 1.5 microg m(-3). Two different types of aerosol were identified at the rural background site on Bhola Island during southerly synoptic flow by means of trajectory analysis: air masses were transported from the Bay of Bengal to the sampling site in all cases. However, during "Period 1" they experienced longer residence times over the Indian Ocean, while the "Period 2" trajectories came along the Indian coast or passed over the Indian continent. During Period 1 the concentration levels of soluble ions were a factor of 4-6 lower than during Period 2. The concentrations of EC, OC and K differed less than a factor of 1.5 between the two periods. The Period 1 aerosol showed similarities to the haze layers observed during winter-monsoon conditions south of India during the INDOEX experiment. Based on EC/TC and K/EC ratios we find that around 80% of the carbonaceous aerosol from Period 1 in Bhola is from fossil fuel and only around 50% from Period 2. Absolute concentrations of carbonaceous species, soluble ions and trace metals indicate that the background site on Bhola Island is affected by emissions from urbanized regions of Southeast Asia.  相似文献   
2.
生态学与经济学的合流   总被引:2,自引:0,他引:2  
生态学家和经济学家在环境问题上各持己见,误解很深。近年来,生态学家和经济学家逐渐认识到了合作的重要性。但是,他们的合作一直磕磕碰碰。其中,最大的分歧在于如何合作才是最有效的。促进双方的沟通和理解可使经济学家更多地将环境问题纳入经济范畴,使生态学家探索运用经济手段解决环境问题的新思路。  相似文献   
3.
Environmental Science and Pollution Research - This study explores the symmetric and asymmetric effects of physical infrastructure on energy consumption, economic growth, and air pollution of...  相似文献   
4.
Environmental Science and Pollution Research - Heat shock proteins (HSPs) are a family of proteins that are expressed by cells in reply to stressors. The changes in concentration of HSPs could be...  相似文献   
5.
Environmental Science and Pollution Research - This empirical study investigates the dynamic effects of economic freedom on economic growth and air quality for Pakistan over the period...  相似文献   
6.
Environmental Science and Pollution Research - Maize tolerance potential to oil pollution was assessed by growing Zea mays in soil contaminated with varying levels of crude oil (0, 2.5 and...  相似文献   
7.
The current experiment was conducted to evaluate the effects of feeding dried sweet orange peel (SOP) and lemon grass leaves (LGL) as feed additives on broiler growth performance, serum metabolites, and antioxidant status. A total of 192-day-old (Ross 308) broiler chickens were distributed randomly into 4 dietary treatments with 4 replicates per each treatment. The dietary treatments included a control diet without any feed additive (T1), a diet containing 0.8 % SOP (T2), a diet containing 0.8 % LGL (T3), and a diet containing combination of 0.4 % SOP?+?0.4 % LGL (T4) was fed during the growth period from 22 to 42 days. Feed intake (FI), body weight gain (BWG), feed conversion ratio (FCR), carcass traits, serum components, and antioxidant status were measured. At the end of the experimental period, the results indicated that supplementation of SOP and LGL alone or in combination did not significantly (P?>?0.05) affect BWG, FI, FCR, and carcass characteristics in broiler chickens. Serum total protein was increased significantly (P?<?0.05) in T3 and T4 compared to the other treatments. Also, serum globulin increased significantly (P?<?0.05) in the treated groups. Serum glucose, low density lipoprotein, triglyceride, and very low density lipoprotein decreased significantly (P?<?0.05) in the treatment groups, while cholesterol and high-density lipoprotein decreased in T2 compared to the other groups. Significantly (P?<?0.05) higher total antioxidant status was observed in T2 compared to the other treatments. In conclusion, these results indicate that SOP, LGL, and their combination may positively modify some serum components and the antioxidant status without any beneficial effect on growth performance and carcass traits in broiler chickens.  相似文献   
8.
Environment, Development and Sustainability - Economic, environmental, and social imperatives make sustainability-oriented entrepreneurship an indispensable phenomenon of the day, yet only sparse...  相似文献   
9.
This paper analyzes the United Nations Organization's Kyoto Protocol nations to address two questions. First, what are the environmental production efficiency rankings of these nations? Second, is there a relationship between a nation's ratification status and its environmental production efficiency ranking? Our findings suggest that the nations that have ratified the Kyoto Protocol are more likely to be environmentally production efficient as compared to the nations that have not ratified the Protocol.  相似文献   
10.
This study explores the interlinkages among population, environment and poverty and presents empirical evidence in a developing country like Pakistan. It gives alternative views on population environment linkages. It explains poverty trap, market based harmony, and dual effect of poverty on the basis of a link between population growth and natural resource degradation. In addition, the paper also highlights social and political instability through population-poverty-environment spiral. It also presents empirical evidence on population-environment-poverty nexus in Pakistan. It also compares environmental sustainability index and human development index for selected Asian countries. The paper also gives scores for different components of environmental sustainability index for Pakistan and compares these with India. The paper concludes that the causal relationship between poverty and environment works in both directions, often through changes in GDP and population. Population stress does not have any significant direct effect on all aspects of environmental status in Pakistan.
Himayatullah KhanEmail:
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