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281.
我国电子废弃物回收管理发展现状   总被引:1,自引:0,他引:1  
我国的电子废弃物存在着产量大、资源化率低、污染危害严重等问题,其回收处理形势十分严峻。文章简要阐述了典型发达国家的电子废弃物回收体系概况,总结了我国电子废弃物回收方面的相关立法管理和具体工程实践,分析了当前国内回收体系存在的弊端,并对最新实施的家电以旧换新政策进行了重点评述,分析了其在完善我国电子废弃物正规回收体系上取得的积极成果和重要意义。同时,就我国电子废弃物回收管理体系的发展,结合相关学者的研究成果,提出了相应的措施和建议。  相似文献   
282.
浅谈淮南矿区采煤沉陷治理新思路   总被引:1,自引:0,他引:1  
许磊 《能源环境保护》2012,26(1):42-44,51
淮南市煤炭资源丰富,随着煤炭的大规模开发,也造成了采煤塌陷地的产生。采煤塌陷地的出现使得矿区耕地数量急剧减少,地质环境受到严重破坏,生态环境受到严重污染,进而引发了一系列社会问题。作为国家首批循环经济试点单位,淮南矿业集团已把建设绿色环保、和谐文明的能源基地归入四大发展战略之中,加大了对采煤沉陷区的综合治理。本论文在总结以往淮南矿区采煤沉陷治理状况的同时,介绍了一些最近涌现出的治理新思路,并从中得到一些企业谋求发展的思考和启发。  相似文献   
283.
新常态下环境保护新形势研究   总被引:2,自引:2,他引:0  
受工业化阶段转换、需求结构调整两个新常态本质因素的影响,我国经济增速、产业结构、重工业产能、能源需求及社会阶层正在发生结构性变化,经济增长新旧动力出现转换,由过去依靠劳动力成本、企业规模、资源环境低价的数量扩张型增长向依靠深化改革和创新驱动带来的效率质量提升型增长转变。经济发展阶段的新变化、新特点,使得环境压力有望高位舒缓,环境保护有望从临界点向转折点改变,生态文明建设和环境保护也呈现新问题、新要求和新特征。  相似文献   
284.
A new iron-fly ash packing was studied for reductive transformation of p-nitrotoluene. The packing was made of iron, fly ash and kaolin with the mass ratio of 36:7:2. A reactor was designed to investigate the long-term performance of the packing. The results showed that the reduction of p-nitrotoluene increased with decreasing pH, because the reduction potential of reaction increased with the concentration of H+. The pH was one of the key factors impacting the reductive transformation of p-nitrotoluene. Comparing iron-activated carbon packing with the new iron-fly ash packing, the reduction efficiencies were respectively 76.61% and 75.36% after 20 days. The reduction efficiency for both was around 50% at 40 days. It was evident that these two kinds of packing had no significant difference in their capability for p-nitrotoluene reductive transformation. Compared with iron-activated carbon, the new iron-fly ash packing had obvious advantages in terms of manufacturing costs and environmental pollution degradation. This study showed that the new iron-fly ash packing had good performance in reductive transformation of nitrotoluene compounds.  相似文献   
285.
Collaboration is an increasingly important approach to dealing with complex environmental challenges. Participation of diverse actors in collaborative processes necessitates attention to the use of different forms of knowledge. We use a multi-case study of governance for water in New Brunswick, Canada, to explore knowledge-related concerns that are prominent in collaborative processes. As is common in other contexts, local or lay (experiential) forms of knowledge appeared to play complementary but ultimately subordinate roles to expert technical and scientific knowledge in the cases. Importantly, we found that the distinction between ‘expert’ and ‘local’ knowledge was not at all clear for the many participants. This study reinforces the importance of designing reflexive and flexible processes for encouraging the active engagement and use of knowledge in collaboration.  相似文献   
286.
新型城镇化所存在的资源环境问题及对策初探   总被引:1,自引:1,他引:0       下载免费PDF全文
新型城镇化是我国城镇化发展的必然选择,是我国城镇化健康发展的根本保证。土地资源、水资源、能源等和生态环境是城镇发展的基础和根本保障。城镇化的快速发展导致一系列资源环境问题,因而,城镇化与资源环境有着密切的关系。本文从我国新型城镇化的发展背景、内涵出发,从水资源、土地资源、能源、环境容量几个方面深入探讨了我国新型城镇化所存在的资源环境问题,并在此基础上提出对策,这对于促进新型城镇化的健康发展和我国资源环境的可持续发展均具有重要的学术价值与实践意义。  相似文献   
287.
The cause of poor welfare in broilers is multifactorial, but genotype is a major contributor. Modern broilers have been bred for rapid growth, and this leads to increases in lameness and ascites as the legs and hearts of the heavier birds find it difficult to cope with the extra demands placed on them. Visible lameness indicative of pain is more common in New Zealand than in Europe. The government, however, insists that New Zealand welfare standards are higher than Europe. The government also appears to have a strong antipathy to those demanding better welfare for broilers. Reasons for this antipathy and disparities between government statements and research results are discussed. Government publications reveal that animal welfare is seen as a question of image for market access and that there is little concern with animal welfare as an ethical imperative for its own sake. The Animal Welfare Act in theory makes it an offence to ill treat an animal, but in practice allows exemptions for industrial agriculture. The interests of animals may be better protected by an independent animal welfare advisory service.  相似文献   
288.
Primary steelmaking involves CO2-intensive processes, but the expansion of secondary steel production is limited by the global availability of steel scrap. The present work examines global scrap consumption in the past (1870–2012) and future scrap availability (2013–2050) based on the historical trend. The results reveal that (i) historically, the consumption of old scrap has been insufficient compared with the amounts of discarded steel, and (ii) based on historical scrap consumption, the future availability of scrap will not be sufficient to satisfy the two assumed cases of steel demand. Primary steelmaking is expected to remain the dominant process, at least up until 2050. Under the reference-demand case of 2.19 billion tons in crude steel production by 2050, the total production of pig iron and direct reduced iron could reach 1.35 billion tons. Consumption of old scrap could reach 0.76 billion tons. Because the availability of scrap will be limited in the context of the global total, it is important to research and develop innovative low-carbon technologies for primary steelmaking and to explore their economic viability if we are to aim for achieving large reductions in CO2 emissions from the iron and steel industry.  相似文献   
289.
Abstract:  For many regions worldwide, multiple and often contrasting biogeographic classifications exist that are derived from a variety of taxa and techniques. This presents a challenge for managers who must choose appropriate large-scale spatial frameworks for systematic conservation planning. We demonstrate how systematically collected community data can be used to evaluate existing biogeographic classifications, identify the most appropriate metric for biogeographic patterns seen in other taxonomic groups, and develop an independent biogeographic classification scheme for systematic conservation planning. We evaluated 6 existing biogeographic classifications for New Zealand's nearshore marine environment with community-similarity metrics derived from abundance and presence–absence data for macroalgae (107 species) and mobile macroinvertebrates (44 species). The concordance between community metrics and the previous classifications was high, as indicated by a high multivariate classification success (CS) (74.3–98.3%). Subsequently, we carried out an independent classification analysis on each community metric to identify biogeographic units within a hierarchical spatial framework. The classification derived from macroalgal presence–absence data achieved the highest CS and could be used as a mesoscale classification scheme in which 11 regional groupings (i.e., bioregions) (CS = 73.8–84.8%) are nested within northern and southern biogeographic provinces (CS = 90.3–98.7%). These techniques can be used in systematic conservation planning to inform the design of representative and comprehensive networks of marine protected areas through evaluation of the current coverage of marine reserves in each bioregion. Currently, 0.22% of the territorial sea around mainland New Zealand is protected in no-take marine protected areas in which 0–1.5% of each bioregion represented.  相似文献   
290.
Davies‐Colley, Robert J., David G. Smith, Robert C. Ward, Graham G. Bryers, Graham B. McBride, John M. Quinn, and Mike R. Scarsbrook, 2011. Twenty Years of New Zealand’s National Rivers Water Quality Network: Benefits of Careful Design and Consistent Operation. Journal of the American Water Resources Association (JAWRA) 47(4):750‐771. DOI: 10.1111/j.1752‐1688.2011.00554.x Abstract: This paper reviews New Zealand’s National Rivers Water Quality Network (NRWQN), which is now in its third decade of monitoring. The NRWQN is noteworthy for being operationally stable throughout its history, and the resulting consistency is increasingly valuable for detecting water quality trends and for “anchoring” temporary special purpose monitoring campaigns. The NRWQN was carefully designed following considerable effort to learn from monitoring experiences elsewhere. Monthly visits are made to 77 sites (all near hydrometric stations) on 35 river systems that cumulatively drain about one half of the national landscape. “Core” (routinely measured) variables are: conductivity, pH, temperature, dissolved oxygen, visual clarity, turbidity, colored dissolved organic matter, fecal indicator bacteria, and different forms of nitrogen and phosphorus (italics indicate field measurements). Associated benthic biological monitoring comprises monthly visual assessment of periphyton and annual sampling for macro‐invertebrates. We overview the conception, design, initiation, and operational history of the NRWQN, and highlight the diverse applications of its datasets including numerous scientific applications, national‐scale modeling of material fluxes, and state‐of‐environment reporting and practical water management at both regional and national scale. The qualified success of the NRWQN can probably be attributed to careful (and parsimonious) design and consistent operation.  相似文献   
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