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401.
通过梳理分析环境影响评价相关法中公众参与的规定,对照UNEP有效的公众参与五要素,剖析环境影响评价中公众参与机制的不足,并提出完善环境影响评价中公众参与机制的对策。  相似文献   
402.
文章首先构建了基于建筑面积和产废系数的城市建筑废物产量估算方法体系,进而在二次曲线回归、指数趋势模型、灰色GM(1,1)模型和BP神经网络4种单项预测模型的基础上,建立了以预测有效度为准则的变权重组合模型,以揭示城市建筑废物未来变化趋势。以海南省为例计算和预测了2001-2020年城市建筑废物产量,结果显示:(1)2001-2010年海南省建筑废物总量从219.1万t增加到813.5万t,年平均增长率为12.7%,拆除建筑废物约占建筑废物总产量的70%;(2)2015年海南省建筑废物总量将达到1 621万t,2020年较之增加71.4%,将达到2 769万t;(3)变权重组合预测模型预测有效度好、精度高、误差小,优于4种单项预测模型。预测结果将为海南省建筑废物的处理处置、资源化和综合管理提供科学依据。  相似文献   
403.
404.
水生植物重建工程对小柘皋河富营养化水质的净化效果   总被引:1,自引:0,他引:1  
利用筛选出来的芦苇(Phragmites australis Trin)、茭草〔Zizania latifolia (Griseb.) Stapf〕、香蒲(Typha orientalis Presl.)、菱角(Trapa natans Linn.)、莲(Nelumbo nucifera Gaertn)和菹草(Potamogeton crispus Linn.)6个工具物种,在小柘皋河道内进行水生植物群落重建恢复试验工程,并对该河道工程区内的水质进行1 a检测. 结果表明:恢复后小柘皋河植被面积占整个河道的65%~75%,河道水生植物年生产量约1.42×106 kg(以湿质量计),相当于1.98×1012 J(能量);河道内的水生植物都具有一定的抗水力冲击负荷能力,能适应河道污水水质和水量均不稳定的动态变化特征,并对污水中CODCr,TN,NO3--N,TP和NH4+-N等均有去除作用,去除率平均值分别为23.61%,25.00%,26.37%,32.93%和33.55%.   相似文献   
405.
Objective: The objective of this study was to estimate the safety benefits of in vehicle lane departure warning (LDW) and lane keeping aid (LKA) systems in reducing relevant real-world passenger car injury crashes.

Methods: The study used an induced exposure method, where LDW/LKA-sensitive and nonsensitive crashes were compared for Volvo passenger cars equipped with and without LDW/LKA systems. These crashes were matched by car make, model, model year, and technical equipment; that is, low-speed autonomous emergency braking (AEB) called City Safety (CS). The data were extracted from the Swedish Traffic Accident Data Acquisition database (STRADA) and consisted of 1,853 driver injury crashes that involved 146 LDW-equipped cars, 11 LKA-equipped cars, and 1,696 cars without LDW/LKA systems.

Results: The analysis showed a positive effect of the LDW/LKA systems in reducing lane departure crashes. The LDW/LKA systems were estimated to reduce head-on and single-vehicle injury crashes on Swedish roads with speed limits between 70 and 120 km/h and with dry or wet road surfaces (i.e., not covered by ice or snow) by 53% with a lower limit of 11% (95% confidence interval [CI]). This reduction corresponded to a reduction of 30% with a lower limit of 6% (95% CI) for all head-on and single-vehicle driver injury crashes (including all speed limits and all road surface conditions).

Conclusions: LDW/LKA systems were estimated to lower the driver injury risk in crash types that the systems are designed to prevent; that is, head-on and single-vehicle crashes. Though these are important findings, they were based on a small data set. Therefore, further research is desirable to evaluate the effectiveness of LDW/LKA systems under real-world conditions and to differentiate the effectiveness between technical solutions (i.e., LDW and LKA) proposed by different manufacturers.  相似文献   

406.
State of the environment reporting (SoER) is a well-established and widely applied environmental management tool in the South African context. Despite a wealth of knowledge about conducting and preparing SoERs, there is a paucity of research on the effect SoER has had on decision-making at the local government sphere. This study investigated the effect of SoER on decision-making for a sample of municipalities in the Gauteng Province of South Africa. The methodology relied on interviews with key role players, which include the ‘‘environmental function’' as well as ‘‘other functions’' responsible for infrastructure development and planning within the municipalities. The results show that notwithstanding the extensive time and resources spent on SoER, it appears to have had a limited effect on decision-making, especially beyond the environmental function. Recommendations to improve the influence of SoER on decision-making in developing countries include improved clarity on the purpose and home of SoER within municipalities, adequate budget and capacity, and effective cooperative governance both within the municipalities, and with other spheres of government.  相似文献   
407.
Large scale rainwater harvesting (LSRWH) is a promising alternative to address security and flood issues in urban areas. The development and planning of a LSRWH for an eco-community involves comprehensive site-planning, systems planning and design, which includes the rainwater source collection (roof) to the storage tank, the distribution and allocation system. This paper describes a new technique for designing a LSRWH for a community of 200 houses with an average of 4 persons per house and an average total daily water demand of 160 m3. It was found that the optimal size storage tank for a 20,000 m2 roof area is 160 m3 with a 60% reliability. The application of this model to the case study revealed a significant water saving up to 58% .The total cost for this system is 443,861 USD over a life-span of 25 years.  相似文献   
408.
2009年底,鄱阳湖生态经济区正式成为为国家战略,区域内各地都在不断探索生态与经济协调发展的新路,良好的生态环境对气候调节和生物多样性保护起着重要作用,也对当地经济的可持续发展起到了促进作用。但是由于环境执法过程中的一些问题的存在,如:相关环境立法的不完善,环保部门执法权力有限,企业违规成本低、守法执法成本高,公众环保意识淡薄等,致使鄱阳湖生态经济区内破坏环境的事件频频发生。为提高执法能效,应当完善环境立法,将环保指标纳入地方考核体系,通过立法以提高违规企业的违法成本,建立多部门联合治理机制,加大环境保护的宣传力度。  相似文献   
409.
提出一套完整的温室气体与大气污染物协同控制效应评估与规划方法:首先,采用排放因子法分别计算减排措施(减排主体)对各类温室气体(全球污染物)和局地大气污染物减排量;其次,以《中华人民共和国环境保护税法》规定的污染物当量值、税额,以及碳排放权交易价格、IPCC发布的温室气体全球增温潜势(GWP)值等参数为依据,将全球和局地...  相似文献   
410.
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