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361.
中国能源可持续发展区域差异及其因素分析 总被引:3,自引:0,他引:3
该文在明晰中国能源可持续发展内涵的基础上,从能源足量、可持续、合理供给;能源与水、土地、森林等资源配套能力;国家可持续能源政策与地区规划的融合,减缓环境资源的损耗;环境可持续性四个目标出发,构建了区域能源可持续发展指标体系。从定量的角度刻画中国能源可持续发展的区域差异,解析影响中国能源可持续发展的主要因素。研究结果表明,可持续能源政策与环境的可持续性是制约能源可持续发展的关键环节;能源与森林、土地资源的配套能力是重要基础;能源供应能力是核心所在;从中国东、中、西部来看,西部地区是中国能源可持续性最强的地区,中部次之,东部能源可持续性最弱;从中国八大区域来看,能源可持续性沿海地区最弱,东北和长江中游地区次之,大西北、西南和黄河中游地区最强。本文作者最后认为多元化发展,提升能源供应能力;建立健全环境税收制度,增强环境可持续性;因地制宜,是促进中国区域能源可持续发展的必然选择。 相似文献
362.
中国现代城镇化发育的能源消费 总被引:2,自引:0,他引:2
城镇是现代社会财富积累的中心。矿物燃料为主的一次能源不仅是现代人类社会发展的基本动力来源,也是现代城镇化发育的基本动力来源。随着城镇化发育不断走向成熟,城镇的生存和发展对能源消费的依赖日趋强烈。这种消费需求不仅体现在总量增长方面,而且更体现在质量提高方面。世界和中国的实践均证明了这一点。所不同者,在产业发展政策和能源消费政策的作用下,中国现代城镇化发育的能源消费表现出明显的不尽人意:第一,能源消费总量增长迅速,甚至进入21世纪以来也是如此;第二,能源消费结构演进缓慢、特别是进入国家城镇化快速发育阶段后的表现更是如此;第三,能源产出效率提高有限,甚至出现一定程度的倒退。如此能源消费特征,对中国城镇化的持续发育构成了巨大挑战,因此,建议加快城镇产业结构调整、推进能源消费结构演进和提高城镇能源消费质量。 相似文献
363.
蓝藻水华暴发已成为全球性生态环境问题。太湖作为流域重要的水源地,2007年蓝藻水华事件的暴发引起公众的高度关注。运用问卷调查法,研究无锡市区489名公众的太湖蓝藻水华生态风险感知特征及其主要影响因素。研究结果表明:蓝藻水华生态风险被公众知觉为总体风险是陌生和完全可控的;蓝藻水华暴发原因是陌生和不可控的,这是引起公众风险意识的主要因素。影响公众蓝藻水华生态风险感知水平的主要因素有媒体、信息和个体因素。报纸广播电视是主要的媒体因素。信息因素有灾害信息、灾害治理信息、政府防范措施信息。灾害治理信息的影响作用最大,其次是灾害信息和政府防范措施信息。不同性别、年龄段、教育程度、收入水平及职业的人群,对不同类别的风险信息关注程度不同,影响到个体风险偏好的不同。研究结果有助于决策者更全面地理解蓝藻水华风险的本质,开展风险沟通,针对不同特征的人群选择有效的风险管理方案。〖 相似文献
364.
Contamination status of dioxins in sediment cores from the Three Gorges Dam area, China 总被引:1,自引:0,他引:1
Lei Chen Yonghong Bi Kongxian Zhu Zhengyu Hu Wei Zhao Bernhard Henkelmann Silke Bernhöft Cedrique Temoka Karl-Werner Schramm 《Environmental science and pollution research international》2013,20(6):4268-4277
In order to screen dioxin pollution in sediment of Three Gorges Dam (TGD) area, three sediment cores were obtained from two sites in 2010~2011; each core was divided into different samples with every 10 cm depth. Sediment dating determined by radiometry (137Cs, 210Pb) and concentrations of dioxins were analyzed by high-resolution gas chromatography/mass spectrometry. The results indicated: Sediment dating showed no significant difference among all the samples from the same core and the two locations (ANOVA, p?>?0.05). The total amount of polychlorinated dibenzo-p-dioxins (PCDD)/Fs in all sample ranged from 30.7 to 371 pg/g dry weight (d.w.), with the mean value of 66.2 pg/g d.w. PCDDs occupied 60.33~85.22 % of dioxins in each sample, and PCDFs contributed to a very small extend. There was no significant difference in the dioxin concentration between 2010 and 2011 and in the two locations (t test, p?>?0.05), but the vertical distribution of dioxins showed significant different in different depths. Toxic equivalent (TEQ) (WHO 2005, Humans) of samples ranged from 0.15 to 1.60 pg/g d.w.; the mean was 0.41 pg/g d.w. No significant difference was found in TEQ between 2010 and 2011(t test, p?>?0.05). It could be concluded that the distribution of dioxins showed the spatial heterogeneous which resulted from the strong mixing and sediment deposition characteristics. Dioxin concentration in sediment cores was low with very low environmental risk potential. Dioxins at the two sites had the same origin, and exogenous input was the main source. It is the first report on the dioxins concentrations in sediment cores in the TGD area. 相似文献
365.
Hong-Guang Guo Nai-Yun Gao Wen-Hai Chu Lei Li Yong-Ji Zhang Jin-Shan Gu Yu-Liang Gu 《Environmental science and pollution research international》2013,20(5):3202-3213
Photochemical degradation of fluoroquinolone ciprofloxacin (CIP) in water by UV and UV/H2O2 were investigated. The degradation rate of CIP was affected by pH, H2O2 dosage, as well as the presence of other inorganic components. The optimized pH value and H2O2 concentration were 7.0 and 5 mM. Carbonate and nitrate both impeded CIP degradation. According to liquid chromatography–tandem mass spectrometry analysis, four and 16 products were identified in UV and UV/H2O2 system, respectively. Proposed degradation pathways suggest that reactions including the piperazinyl substituent, quinolone moiety, and cyclopropyl group lead to the photochemical degradation of CIP. Toxicity of products assessed by Vibrio qinghaiensis demonstrated that UV/H2O2 process was more capable on controlling the toxicity of intermediates in CIP degradation than UV process. 相似文献
366.
Ming-Hong Wu Liang Tang Gang Xu Jing Ma Ning Liu Liang Wang Jian-Qiu Lei 《Environmental science and pollution research international》2013,20(4):2651-2660
Fourteen and 17 sediment samples were collected from three main rivers of Shanghai in July and November, respectively. Eight polybrominated diphenyl ether (PBDE) congeners (BDE-28, BDE-47, BDE-99, BDE-100, BDE-153, BDE-154, BDE-183, and BDE-209) were detected in these samples to clarify the pollution status in the metropolis. Instrumental analyses showed that the concentrations of ∑8PBDEs ranged from 10.97 to 64.05 ng/g dry weight (dw), with an average value of 29.71 ng/g dw. BDE-209 was the predominant congener accounting for more than 97 % of total PBDEs, followed by BDE-47 and BDE-99. Remarkable spatial and seasonal distributions of PBDE concentrations were observed, suggesting that local sources, seasonal climates, and hydrologic conditions might be the influencing factors. Moderate correlations (r 2?=?0.28–0.51, p?<?0.05) were found between total organic carbon and PBDEs, which indicated that organic carbon content influenced the distributions of PBDEs in sediment of Shanghai at some extent. Hazard quotients revealed PBDEs posed no potential risk to benthic organisms in the study area at present. 相似文献
367.
Lei Tong Xu Liao Jinsheng Chen Hang Xiao Lingling Xu Fuwang Zhang Zhenchuan Niu Jianshuan Yu 《Environmental science and pollution research international》2013,20(4):2603-2615
With the rapid urbanization, the southeast coastal cities of China are facing increasing air pollution in the past decades. Large emissions of VOCs from vehicles and petrochemical factories have contributed greatly to the local air quality deterioration. Investigating the pollution characteristics of VOCs is of great significance to the environmental risk assessment and air quality improvement. Ambient VOC samples were collected simultaneously from nine coastal cities of southeast China using the Tedlar bags, and were subsequently preprocessed and analyzed using a cryogenic preconcentrator and a gas chromatography–mass spectrometry system, respectively. VOC compositions, spatial distributions, seasonal variations and ozone formation potentials (OPFs) were discussed. Results showed that methylene chloride, toluene, isopropyl alcohol and n-hexane were most abundant species, and oxygenated compounds, aromatics and halogenated hydrocarbons were most abundant chemical classes (62.5–95.6 % of TVOCs). Both industrial and vehicular exhausts might contribute greatly to the VOC emissions. The VOC levels in the southeast coastal cities of China were sufficiently high (e.g., 6.5 μg?m?3 for benzene) to pose a health risk to local people. A more serious pollution state was found in the southern cities of the study region, while higher VOC levels were usually observed in winter. The B/T ratio (0.26?±?0.09) was lower than the typical ratio (ca. 0.6) for roadside samples, while the B/E (1.6–7.6) and T/E (7.2–26.8) ratios were higher than other cities around the world, which indicated a unique emission profile in the study region. Besides, analysis on ozone formation potentials (OFPs) indicated that toluene was the most important species in ozone production with the accountabilities for total OFPs of 22.6 to 59.6 %. 相似文献
368.
369.
Concentrations of 16 polycyclic aromatic hydrocarbons (PAHs), 16 phthalate esters (PAEs), eight organochlorine pesticides (OCPs) and seven polychlorinated biphenyls (PCBs) in 17 frequently-consumed varieties of vegetables collected from 48 sites in Huizhou were measured. Concentrations of PAHs and PAEs of leafy vegetables were higher than those of gourd and fruit vegetables but it was the opposite for OCPs and PCBs. A questionnaire of 450 local residents on vegetable consumption showed that the total vegetable ingested rates of females and males were 278.80 g person−1 d−1 and 282.92 g person−1 d−1, respectively. The weight-specific daily intakes of pollutants by females were higher than those by males because of differences in body weight. Twenty-seven pollutants were used to assess the potential risk to human health by calculating target hazard quotient (THQ) values. Results showed that the risk to females was higher than for males. OCPs were the major contributors to the risk for both females and males. The main risks were from consumption of eggplant, Chinese lettuce and luffa and were significantly related to the contents of di-nonyl phthalate, β-hexachlorocyclohexane, γ-hexachlorocyclohexane, p,p-dichlorodiphenyltrichloroethane and p,p-dichlorodiphenyl dichloroethane in vegetables. Although the THQ values induced by individual pollutants were relatively low, the total THQ values induced by 27 pollutants were above 1 in some administrative regions of Huizhou, which might give cause for concern. 相似文献
370.
养殖固体废物掺杂磷肥工艺中养殖固体废物与酸的反应直接影响其有机组成。以鸡粪为研究对象,采用L16(45)正交试验研究了鸡粪粒径、酸浓度、鸡粪与酸溶液质量比、反应温度和反应时间对鸡粪在硝酸和磷酸溶液中水解过程的影响。结果表明,硝酸溶液中影响因素显著性依次为鸡粪与硝酸质量比、反应时间、硝酸浓度、鸡粪粒径、反应温度,最优工艺条件为鸡粪粒径0.20mm、硝酸质量分数15%、鸡粪与硝酸质量比0.2∶1.0、反应温度95℃、反应时间4h;在磷酸溶液中影响因素显著性依次为鸡粪与磷酸质量比、反应温度、鸡粪粒径、磷酸浓度、反应时间,鸡粪水解率与反应温度间呈正相关关系,最优工艺条件为鸡粪粒径0.40mm、磷酸质量分数60%、鸡粪与磷酸质量比0.1∶1.0、反应温度95℃、反应时间8h。鸡粪比表面积及其单位质量耗酸量、美拉德反应是制约鸡粪在硝酸和磷酸中水解反应的内因。研究结果为养殖固体废物掺杂有机磷肥的研发和推广提供了理论基础。 相似文献