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211.
This paper aims to estimate the effects of changing life style and consumption demands driven by income growth and urbanization on increase of energy requirements in China, and es-timate the impacts of improvement in household consumption on mitigating energy requirements towards 2020, based on input-out-put analysis and scenarios simulation approach. The result shows that energy requirement per capita has increased by 159% for urban residents and 147% for rural residents from 1995 to 2004. Growth in household consumption driven by income growth and urbanization may induce a successive increase in energy require-ments in future. Per capita energy requirements of urban residents will increase by 240% during 2002-2015 and 330% during 2002-2020. Urbanization might lead to 0.75 billion ton of increment of energy requirements in 2020. About 45%-48% of total energy requirements in China might be a consequence of residents’ life styles and the economic activities to support consumption demands in 2020. Under low-carbon life style scenario, per capita energy requirements of urban residents may decline to 97% in 2015 and 92% in 2020 in contrast with baseline scenario. That implies that China needs to pay a great attention to developing green low-carbon life style in order to realize mitigation target towards 2020.  相似文献   
212.
在2004—2007年旅游统计数据的基础上,运用主成分分析法对西部地区旅游业发展水平进行了综合评价。结果表明,尽管西部地区旅游资源优势明显,但旅游业发展的整体水平还较低,旅游资源优势尚未充分转化为经济优势,且各地区旅游业发展水平差异较大。基于上述分析,结合西部地区实际情况和旅游业的未来发展趋势,提出加快西部地区旅游业发展的对策和建议。  相似文献   
213.
Eero Asmala  Laura Saikku 《Ambio》2010,39(2):126-135
Ongoing eutrophication is changing the Baltic Sea ecosystem. Aquaculture causes relatively small-scale nutrient emissions, but local environmental impact may be considerable. We used substance flow analysis (SFA) to identify and quantify the most significant flows and stocks of nitrogen (N) and phosphorus (P) related to rainbow trout aquaculture in Finland. In 2004–2007, the input of nutrients to the system in the form of fish feed was 829 t N year−1 and 115 t P year−1. Around one-fifth of these nutrients ended up as food for human consumption. Of the primary input, 70% ended up in the Baltic Sea, directly from aquaculture and indirectly through waste management. The nutrient cycle could be closed partially by using local fish instead of imported fish in rainbow trout feed, thus reducing the net load of N and P to a fraction.  相似文献   
214.
We investigated the concentrations of 22 essential and non-essential elements among a community of Procellariiformes (and their prey) to identify the extent to which trophic position and foraging range governed element accumulation. Stable isotope analysis (SIA) was used to characterise trophic (δ15N) and spatial patterns (δ13C) among species. Few consistent patterns were observed in element distributions among species and diet appeared to be highly influential in some instances. Arsenic levels in seabird red blood cells correlated with δ15N and δ13C, demonstrating the importance of trophic position and foraging range for arsenic distribution. Arsenic concentrations in prey varied significantly across taxa, and in the strength of association with δ15N values (trophic level). In most instances, element patterns in Procellariiformes showed the clearest separation among species, indicating that a combination of prey selection and other complex species-specific characteristics (e.g. moult patterns) were generally more important determining factors than trophic level per se.  相似文献   
215.
Sewage samples from 4 hospitals, 1 nursery, 1 slaughter house, 1 wastewater treatment plant and 5 source water samples of Chongqing region of Three Gorge Reservoir were analyzed for macrolide, lincosamide, trimethoprim, fluorouinolone, sulfonamide and tetracycline antibiotics by online solid-phase extraction and liquid chromatography-tandem mass spectrometry. Results showed that the concentration of ofloxacin (OFX) in hospital was the highest among all water environments ranged from 1.660 μg/L to 4.240 μg/L and norfloxacin (NOR, 0.136-1.620 μg/L), ciproflaxacin (CIP, ranged from 0.011 μg/L to 0.136 μg/L), trimethoprim (TMP, 0.061-0.174 μg/L) were commonly detected. Removal range of antibiotics in the wastewater treatment plant was 18-100% and the removal ratio of tylosin, oxytetracycline and tetracycline were 100%. Relatively higher removal efficiencies were observed for tylosin (TYL), oxytetracycline (OXY) and tetracycline (TET)(100%), while lower removal efficiencies were observed for Trimethoprim (TMP, 1%), Epi-iso-chlorotetracycline (EICIC, 18%) and Erythromycin-H2O (ERY-H2O, 24%). Antibiotics were removed more efficiently in primary treatment compared with those in secondary treatment.  相似文献   
216.
In urban cities in Southern China, the tissue S/N ratios of epilithic mosses (Haplocladium microphyllum), varied widely from 0.11 to 0.19, are strongly related to some atmospheric chemical parameters (e.g. rainwater SO42−/NH4+ ratios, each people SO2 emission). If tissue S/N ratios in the healthy moss species tend to maintain a constant ratio of 0.15 in unpolluted area, our study cities can be divided into two classes: class I (S/N > 0.15, S excess) and class II (S/N < 0.15, N excess), possibly indicative of stronger industrial activity and higher density of population, respectively. Mosses in all these cities obtained S and N from rainwater at a similar ratio. Sulphur and N isotope ratios in mosses are found significantly linearly correlated with local coal δ34S and NH4+-N wet deposition, respectively, indicating that local coal and animal NH3 are the major atmospheric S and N sources.  相似文献   
217.
To study the Pu concentration and isotope ratio distributions present in China, the 239+240Pu total activities and 240Pu/239Pu atom ratios in core soil samples from Hubei Province in central China were investigated using Accelerator Mass Spectrometry (AMS). The activities ranged from 0.019 to 0.502 mBq g−1 and the 239+240Pu inventories of 45 and ∼55 Bq m−2 agree well with that expected from global fallout. The 240Pu/239Pu atom ratios in the soil ranged from 0.172 to 0.220. The ratios are similar to typical global fallout values. Hence, any close-in fallout contribution from the Chinese nuclear weapons tests, mainly conducted in the 1970s, must have either been negligible or had a similar 240Pu/239Pu ratio to that of global fallout. The top 10 cm layer of the soil contributes ∼90% of the total inventory and the maximum concentrations appeared in the 2-4 cm or 4-6 cm layers. It is suggested that climatic conditions and organic content are the two main factors that affect the vertical migration of plutonium in soil.  相似文献   
218.
This study focuses on the cesium-137 (137Cs) contamination in grass and in different compartments of oak trees growing in ecosystems, located in the zone with sub-mediterranean climate in South Bulgaria, characterized with high summer temperatures, low precipitation and often periods of drought. In 2008, three experimental sites - PP1, PP2, PP3 - were sampled in oak ecosystems from Maleshevska Mountain at 900 m above sea level. Samples from grass species and oak tree leaves, branches with different diameter, wood disks and bark were analyzed for 137Cs activity with γ-spectrometry. The soil-to-plant transfer factor (TF) values for 137Cs were estimated differentiating different tree compartments. Our findings showed relatively high activity concentrations of 137Cs in oak trees even 22 years after the Chernobyl accident. The grass under oak was less contaminated compared with the oak trees. The different organs of oak trees could be distinguished according to the 137Cs contamination as follows: bark > branches (d < 1 cm) > leaves > branches (d > 3 cm) > wood. The relatively higher contamination of bark compared with the new-formed biomass suggested that a significant part of 137Cs was accumulated as a result of direct adsorption at the time of the main contamination event. The TF values obtained and the presence of 137Cs in the branches, leaves and in the wood formed after 1986 confirmed that 22 years after the contamination, the main mechanism of 137Cs entrance in tree biomass was the root uptake.  相似文献   
219.
Anthropogenic Pu isotopes are important geochemical tracers for sediment studies. Their distributions and sources in the water columns as well as the sediments of the North Pacific have been intensively studied; however, information about Pu in the Southeast Asian seas is limited. To study the isotopic composition of Pu, and thus to identify its sources, we collected sediment core samples in the South China Sea and the Sulu Sea during the KH-96-5 Cruise of the R/V Hakuho Maru. We analysed the activities of 239+240Pu and the atom ratios of 240Pu/239Pu using isotope dilution sector-field inductively coupled plasma mass spectrometry (SF-ICP-MS). The 240Pu/239Pu atom ratios in the sediments of both areas (inventory weighted mean: 0.251 for the South China Sea and 0.280 for the Sulu Sea) were higher than the global fallout value (0.178 ± 0.019), suggesting the existence of Pu from the Pacific Proving Grounds in the North Pacific. Low inventories of 239+240Pu in sediments were observed in the South China Sea (3.75 Bq/m2) and the Sulu Sea (1.38 Bq/m2). Most of the Pu input is still present in the water column. Scavenging and benthic mixing processes were considered to be the main processes controlling the distribution of Pu in the deep-sea sediments of both study areas.  相似文献   
220.
1949年以来中国环境与发展关系的演变   总被引:2,自引:0,他引:2  
从IPAT方程出发,发现了环境影响随着经济发展或时间的演变依次遵循三个"倒U型"曲线规律,即环境影响强度的倒U型曲线、人均环境影响的倒U型曲线和环境影响总量的倒U型曲线。根据此规律,可以将该演化过程划分为四个阶段即:环境影响强度高峰前阶段、环境影响强度高峰到人均环境影响量高峰阶段、人均环境影响量高峰到环境影响总量高峰阶段以及环境影响总量稳定下降阶段。在环境演变的不同阶段,主要驱动力存在着明显的差异。在环境影响强度高峰前阶段,资源消耗或污染物排放增长更多地由资源或污染密集型技术进步驱动;在资源消耗或污染物强度高峰到人均资源消耗或污染物排放高峰阶段,主要由经济增长驱动;而在人均资源消耗或污染物排放高峰到资源消耗或污染物排放总量高峰阶段以及总量高峰以后的发展阶段,则主要由节约高效技术或污染减排技术进步来驱动。实证分析表明,中国目前环境与发展关系基本上处于经济增长主要驱动的环境影响强度高峰向人均环境影响高峰过渡阶段,这同时意味着中国要在短期内实现人均环境影响和环境影响总量高峰的跨越是异常困难的。  相似文献   
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