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991.
徐云飞 《中国环境管理干部学院学报》2011,21(4):15-17,25
针对规划环评的特点,通过秦皇岛经济技术开发区规划环评案例分析,就如何保证规划环境影响评价中公众参与有效性进行了探讨,提出了只有做到广泛的公众代表性、有效的公众参与形式、科学的问卷设计、合理的反馈意见处理,才能发挥公众参与在规划环境影响评价工作中的作用。 相似文献
992.
水污染侵权中的因果关系成立与否决定着民事责任的有无,对受害人的利益影响甚巨,关于因果关系的理论纷繁复杂,水污染侵权中的因果关系认定难度更大,试图在分析各种学说的基础上找到认定水污染侵权中因果关系的可行方法。 相似文献
993.
艺术教育中专才的发掘与培养具有重要的价值和意义。专才的发掘与培养是社会发展刻不容缓的问题,但是目前大学校方和教师还没有专门系统的发掘、引导、培养有专业特长学生的措施和机制。需要从教育体制和学校教师教育方法两个方面来完善专才教育的培养体系。 相似文献
994.
995.
变化环境下北江下游年径流量的加权马尔可夫链预测 总被引:2,自引:0,他引:2
在气候变化和人类活动的影响下,西北江的水文环境发生了重大变化,导致北江下游的来水条件发生变化。采用斯波曼检验(Spearman’s rho test)和Mann-kendall法系统地分析了北江下游的年径流量的变化趋势和变异情况,在此基础上建立了北江下游变化环境下年径流量的加权马尔可夫链预测模型。结果表明:西北江近50年来的大规模联围筑闸、大规模无序采掘河床泥沙等剧烈的人类活动,导致北江下游三水水文站年径流量在1990年左右发生了变异;所建立的加权马尔可夫链预测结果表明,从变异后的序列中统计出来的状态"转移概率"矩阵,能准确地反映出环境变化后年径流量之间的关系,所建立的加权马尔可夫链法预测变化环境下的年径流量是可行的,预测效果也比较好;按文章确定的分级标准,依现有的资料信息推断,环境发生变化后,在未来长期过程中,北江下游出现平水年的机会最大,但年际间的丰枯波动概率也不小。这一结果值得水资源管理部门注意。 相似文献
996.
Human activities produced great impacts on wetlands worldwide. Taking Jiangsu Province, China, as a representative wetland region subject to extensive human activities, the aim of this study is to understand the conversion trajectory and spatial differentiation in wetland change from a multi-scale perspective. Based on multi-temporal Landsat images, it was found that the natural wetlands decreased by 11.2% from 1990 to 2006 in Jiangsu Province. Transition matrices showed that the conversion of natural wetlands to human-made wetlands (mostly aquaculture ponds) was the major form of natural wetland reduction, accounting for over 60% of the reduction. Percentage reduction and area reduc tion of natural wetlands were respectively quantified within different wetland cover zones using a moving window analysis. Average percentage reduction showed a decreasing tendency with increasing wetland cover. The high-cover and mid-cover zone presented the largest area reduction at the scales of 1-2 km and 4-8 km, respectively. Local hotspots of natural wetland reduction were mapped using the equal-interval and quantile classification schemes. The hotspots were mostly concentrated in the Lixiahe marshes and the coastal wetland areas. For the area reduction hotspots, the quantile classification presented larger area and more patches than the equal-interval classification; while an opposite result was shown for the percentage reduction hotspots. With respect to the discontinuous distribution of the natural wetlands, area reduction could be more appropriate to represent reduction hotspots than percentage reduction in the study area. These findings could have useful implications to wetland conservation. 相似文献
997.
Xu P Wang W Yang L Zhang Q Gao R Wang X Nie W Gao X 《Environmental monitoring and assessment》2011,179(1-4):443-456
Aerosol size distributions, trace gas, and PM(2.5) concentrations have been measured in urban Jinan, China, over 6 months in 2007 and 2008, covering spring, summer, fall, and winter time periods. Number concentrations of particles (10-2,500 nm) were 16,200, 13,900, 11,200, and 21,600 cm(?-3) in spring, summer, fall, and winter, respectively. Compared with other urban studies, Jinan has higher number concentrations of accumulation-mode particles (100-500 nm) and particles (10-2,500 nm), but lower concentrations of ultrafine particles (10-100 nm). The number, surface and volume concentrations, and size distributions of particles showed obvious seasonal variation and are also influenced by traffic emissions. Through correlation analysis, traffic emissions are proposed to be a more important contributor to Atkien-mode and accumulation-mode particles than coal firing. Around midday, the presence of nanoparticles and new particle formation is limited to pre-existing particles from traffic emissions and the mass transport of particles from suburban and rural areas. Compared with other studies in urban areas of Europe and the USA, the variation of particle number concentration and related gas concentration in Jinan between weekdays and weekends is smaller and the reasons has been deduced. 相似文献
998.
Xu H Bi XH Feng YC Lin FM Jiao L Hong SM Liu WG Zhang XY 《Environmental monitoring and assessment》2011,183(1-4):581-592
To understand the origin and chemical characteristics of precipitation in Hangzhou, rainwater samples were collected from June 2006 to May 2008. All samples were analyzed for pH, electrical conductivity, and major ions (NH??, Ca2?, Mg2?, Na?, K?, SO?2?, NO??, F?, and Cl?). Acidification of precipitation in Hangzhou was serious with volume-weighted mean pH value of 4.5, while frequency of acid rain was 95%. The calculated SO?2?/NO?? ratio in Hangzhou precipitation was 2.87, which indicated that the precipitation of Hangzhou belonged to sulfate-based acid rain. The results of acid neutralization analysis showed that not all the acidity in the precipitation of Hangzhou was neutralized by alkaline constituents. The results of sea salt contribution analysis showed that nearly all SO?2?, Ca2?, and Mg2? and 33.7% of K? were of non-sea origins, while all Na? and Cl? and 66.3% of K? originated from sea sources. The principal component analysis which was used to analyze the sources of various ions indicated that chemical compositions of precipitation in Hangzhou mainly came from terrestrial sources, factory emissions, fuel wood burning, and marine sources. 相似文献
999.
Jiansu Mao Yanchun Du Linyu Xu Yong Zeng 《Frontiers of Environmental Science & Engineering》2011,5(4):585-596
Improving eco-efficiency is propitious for saving resources and reducing emissions, and has become a popular route to sustainable development. We define two energy-related eco-efficiencies: energy efficiency (ENE) and greenhouse gas (GHG) emission-related eco-efficiency (GEE) using energy consumption and the associated GHG emissions as the environmental impacts. Using statistical data, we analyze China??s energy consumption and GHG emissions by industrial subsystem and sector, and estimate the ENE and GEE values for China in 2007 as 4.871×107 US$/PJ and 4.26×108 US$/TgCO2eq, respectively. Industry is the primary contributing subsystem of China??s economy, contributing 45.2% to the total economic production, using 79.6% of the energy consumed, and generating 91.4% of the total GHG emissions. We distinguish the individual contributions of the 39 industrial sectors to the national economy, overall energy consumption, and GHG emissions, and estimate their energyrelated eco-efficiencies. The results show that although ferrous metal production contributes only 3.5% to the national industrial economy, it consumes the most industrial energy (20% of total), contributes 16% to the total industrial global warming potential (GWP), and ranks third in GHG emissions. The power and heat sector ranks first in GHG emissions and contributes one-third of the total industrial GWP, although it only consumes about 8% of total industrial energy and, like ferrous metal production, contributes 3.5% to the national economy. The ENE of the ferrous metal and power and heat sectors are only 8 and 2.1×107 US$/PJ, while the GEE for these two sectors are 9 and 4×104 US$/GgCO2eq, respectively; these are nearly the lowest ENE and GEE values among all 39 industry sectors. Finally, we discuss the possibility of ecoefficiency improvement through a comparison with other countries. 相似文献
1000.
Polycyclic aromatic hydrocarbons in effluents from wastewater treatment plants and receiving streams in Tianjin, China 总被引:1,自引:0,他引:1
Weixiao Qi Huijuan Liu Jiuhui Qu Chengzhi Hu Huachun Lan Michael Berg Huimin Ren Wei Xu 《Environmental monitoring and assessment》2011,177(1-4):467-480
Surface water, suspended particulate matter, pore water, and sediment samples were collected and analyzed for polycyclic aromatic hydrocarbons (PAHs) in Yongding New River, South Drainage Canal and North Drainage Canal, which receive most of wastewater from industrial city of Tianjin. PAH concentrations in effluent samples of wastewater treatment plants (WTP) discharging into the South Drainage Canal and North Drainage Canal were quantified for the first time. The results showed that the discharge of the WTPs recently only contributed to the PAH contamination in the canals near the outlets of the WTPs. PAH levels in sediments of the streams were greatly higher than those in soils by riverbank probably due to receiving large amounts of untreated wastewater. Unusually high benz[a] anthracene concentration strongly influenced the seasonal and spatial variation of total PAH concentrations in South Drainage Canal. Paired samples t test of ??Nap, Fl, Phe, Fluo and ??Nap, Phe, Fluo, Chry concentrations, which were dominant components in the air samples from non-heating and heating season, respectively, in the suspended particulate matters from the streams showed that PAH source from air deposition was more important for Yongding New River than that for South Drainage Canal and North Drainage Canal. Source apportionment based on PAH profiles indicated that coal combustion was the major PAH contamination source, and coke oven sources and wood combustion also contributed to the PAH contamination of the streams. This was further indicated by organic petrography analysis. 相似文献