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21.
Schedule 11 of the Environment Act 1995 underpins the requirement for consultation on air quality issues. The ongoing air quality review and assessment process represents one of the largest locally based science policy and communication initiatives ever undertaken in the UK. This paper outlines the practice of consultation and communication for Air Quality Management (AQM) and reviews the interaction between Environmental Health professionals, as the leading actor in the AQM process and other stakeholders involved in air quality consultation, including the public. Results are presented from a widespread questionnaire survey of English local authorities. Data indicate that the majority of air quality consultation has been carried out with statutory consultees (by sending the review and assessment reports) and the public (via websites and leaflets) in the form of information dissemination.  相似文献   
22.
为降低可旋转径向式微粒捕集器中的排气噪声,采用有限元法建立可旋转径向式微粒捕集器声学特性模型,分析得到了其消声特性和传递损失曲线,并采用灰色关联分析方法研究可旋转径向式微粒捕集器结构参数对消声特性的影响程度。结果表明,可旋转径向式微粒捕集器具有降噪能力,且对高频噪声消声效果明显好于低频噪声,平均消声量为20 dB左右;直径比和扩张管锥角是影响可旋转径向式微粒捕集器消声特性的2个主要因素,适当选用小的直径比和扩张管锥角,有利于提高可旋转径向式微粒捕集器的消声性能。  相似文献   
23.
Lindstrom SM  White JR 《Chemosphere》2011,85(4):625-629
Treatment wetlands have a finite period of effective nutrient removal after which treatment efficiency declines. This is due to the accumulation of organic matter which decreases the capacity and hydraulic retention time of the wetland. We investigated four potential solutions to improve the soluble reactive P (SRP) removal of a municipal wastewater treatment wetland soil including; dry down, surface additions of alum or calcium carbonate and physical removal of the accreted organic soil under both aerobic and anaerobic water column conditions. The flux of SRP from the soil to the water column under aerobic conditions was higher for the continuously flooded controls (1.1 ± 0.4 mg P m−2 d−1), dry down (1.5 ± 0.9 mg P m−2 d−1) and CaCO3 (0.8 ± 0.7 mg P m−2 d−1) treatments while the soil removal and alum treatments were significantly lower at 0.02 ± 0.10 and −0.07 ± 0.02 mg P m−2 d−1, respectively. These results demonstrate that the two most effective management strategies at sequestering SRP were organic soil removal and alum additions. There are difficulties and costs associated with removal and disposal of soils from a treatment wetland. Therefore our findings suggest that alum addition may be the most cost effective and efficient means of increasing the sequestering of P in aging treatment wetlands experiencing reduced P removal rates. However, more research is needed to determine the longer term effects of alum buildup in the organic soil on the wetland biota, in particular, on the macrophytes and invertebrates. Since alum effectiveness is time limited, a longer term solution to P flux may favor the organic soil removal.  相似文献   
24.
Apple orchards are highly manipulated crops in which large amounts of pesticides are used. Some of these pesticides lack target specificity and can cause adverse effects in non-target organisms. In order to evaluate the environmental risk of these products, the use of transplanted sentinel organisms avoids side-effects from past events and facilitate comparison of multiple sites in a short time. We released specimens of the terrestrial snail Xeropicta derbentina in each 5 of two kinds of apple orchards with either conventional or organic management strategies plus in a single abandoned orchard. After one month, individuals were retrieved in order to measure acetylcholinesterase (AChE) activity. Mean values of AChE activity were significantly reduced in all conventional apple orchards compared to the others. Results show that the measurement of biomarkers such as AChE inhibition in transplated X. derbentina could be useful in the environmental risk assessment of post-authorized pesticides.  相似文献   
25.
Coastal fisheries provide staple food and sources of livelihood in Pacific Island countries, and securing a sustainable supply is recognised as a critical priority for nutrition security. This study sought to better understand the role of fish for Pacific Island communities during disasters and in disaster recovery. To evaluate community impacts and responses after natural disasters, focus group discussions were held with men and women groups at ten sites across Shefa, Tafea, Malampa and Sanma provinces in Vanuatu. The combined impacts of category 5 Tropical Cyclone Pam (TC-Pam) in March 2015 and prolonged El-Niño induced drought have had a profound impact across much of Vanuatu. Terrestrial systems had been disproportionately impacted with substantial shortages in drinking water, garden crops, cash crops and damage to infrastructure. Localized impacts were noted on marine environments from TC-Pam and the drought, along with an earthquake that uplifted reef and destroyed fishing grounds in Malampa province. Communities in Malampa and Shefa provinces also noted a crown-of-thorns outbreak that caused coral mortality. The significant reduction in terrestrial-based food and income generation capacity generally led to increased reliance on marine resources to cope and a shift in diets from local garden food to rice. However, limited market access, lack of fishing skills and technology in many sectors of the community reduced the capacity for marine resources to support recovery. A flexible management approach allowed protected areas and species to be utilized as reservoirs of food and income when temporarily opened to assist recovery. These findings illustrate that fish and fisheries management is at the center of disaster preparedness and relief strategies in remote Pacific Island communities. High physical capital (e.g. infrastructure, water tanks and strong dwellings) is key for disaster preparedness, but supporting community social capital for the purpose of natural resource management and human capital for diverse adaptation skills can also improve community resilience. Recognizing the humanitarian value that well managed fisheries resources and skilled fishers can play to disaster relief adds another dimension to the imperative of improving management of coastal fisheries and aligning policies across sectors.  相似文献   
26.
光气生产装置的危险性及事故统计分析   总被引:3,自引:3,他引:3  
通过对光气、光气化生产工艺过程存在的危险性分析,笔者认为气相光气化工艺比液相光气化工艺危险性小,而固体光气化生产工艺与气、液相光气生产工艺相比,危险性更小。同时对国内外光气和光气化生产发生事故的原因进行分析探讨,指出事故的原因主要是由管道及设备缺陷、个体防护用品缺乏、设计缺陷及人为失误引起。采用固体光气替代光气参与各种有机合成,与液相或气相光气工艺相比具有安全、反应条件温和、易操作、工艺简便、反应计量准确等优点,因此,固体光气工艺发展前景广阔。  相似文献   
27.
煤矿本质安全特征及管理方法研究   总被引:3,自引:9,他引:3  
分析国内煤矿本质安全管理研究现状及存在问题,进一步讨论煤矿本质安全的内涵。探讨近年来我国煤矿事故发生的致因与根源,指出人的行为安全是我国煤矿本质安全的主要特征。通过研究我国煤矿事故的控制管理,选择事故率作为我国煤矿本质安全判别的参考标准;分析我国煤矿生产的现状与差异,提出了对我国煤矿的本质安全性进行分类判别的思想;从深入开展煤矿安全管理理论研究、加强煤矿安全管理立法、建立煤矿安全管理标准和有效组织机制等方面提出了实现煤矿本质安全的管理策略。  相似文献   
28.
苏北地区农业环境问题及管理方案的探讨   总被引:4,自引:0,他引:4  
配合江苏省“碧海计划”和盐城市海洋经济绿色农业的发展,探讨了现阶段农业环境污染控制的直接政策管理、经济手段和人工生态工程处理三种方案,其中政策管理,如减少化肥农药的施用规定能减少污染,直接经济投入少,但是执行管理成本高,且政策见效慢;经济手段能减少污染,但环境目标达标不确定,且需要完善的市场环境,目前来说,本地区市场机制不完善,会出现“市场失灵”现象;人工湿地生态工程,前期投入大,但管理成本低,环境目标确定,但不能快速削减污染负荷。三种方案各有所长,在实际操作中,应针对不同区域的农业产业状况、方案时间迟度组合使用。  相似文献   
29.
2005年通过对骆马湖水质监测,并结合近几年的监测资料进行了分析,结果表明,氮是骆马湖水体的主要污染物,包括总氮、氨氮和硝酸盐氮,其主要特征是入湖河流、降水、围网养殖和点源带来的污染。  相似文献   
30.
开展了(炉排炉和流化床炉)两种垃圾焚烧底渣与固化剂共同作用下固化市政污泥的工程特性研究。分析了两种底渣化学成份及物理级配上的差异,重点考察了在密封养护情况下,测定了不同底渣固化体的含水率、pH值、无侧限抗压强度及28d渗透系数等工程特性指标。研究结果表明:相同含量的两种底渣固化体含水率及pH相同,且含水率随底渣含量增加而降低,而pH值随底渣含量增加而增加;随着底渣含量增加,级配良好的炉排炉底渣固化体强度比级配不良的流化床底渣固化体强度从高8 kPa增加到30 kPa;受底渣级配的影响,炉排炉底渣固化体渗透系数随底渣含量增加而增大,而流化床底渣固化体渗透系数基本不变。级配良好的炉排炉底渣固化体工程特性优于级配不良的流化床底渣固化体,具有更强的骨架作用。研究成果为污泥及垃圾焚烧底渣填埋处置提供了科学借鉴。  相似文献   
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