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141.
Despite widespread acceptance of sustainability as the ultimate goal of forest management, perspectives about its meaning, significance, and relevant indicators may still differ. This paper examines local perspectives on sustainability, and evaluates their similarities and differences. A systematic procedure based on criteria of proximity, pre-existing rights, dependency, knowledge of forest management, forestry spirit, daily activity, and legal rights was used to identify a small group of relevant stakeholders representing different groups, institutions, and organizations. Using participatory action research (PAR), stakeholders were asked to identify relevant indicators of sustainable forest management. The indicators identified by each stakeholder were then compared to a consolidated list assembled by field facilitators with respect to whether relevant indicators are present or not. Based on the resulting presence/absence matrix, a statistical tool called the simple matching coefficient was used to estimate the similarity measures among the stakeholders' perspectives. In addition, cluster analysis was used to classify groups of stakeholders depending on their similarities to each other. Finally, hypotheses related to the 'closeness' of perspectives among local communities, non-governmental organizations, a timber company, and government organizations, as revealed by their selection of indicators, were tested. Results show that: (a) local communities have different perceptions in terms of what they consider to be important indicators compared to the NGOs, (b) there are significantly different perceptions between the government and the timber companies, and (c) there are also different perceptions between urban and field-based personnel of the same organization.  相似文献   
142.
The Russian natural gas industry is the world's largest producer and transporter of natural gas. This paper aims to characterize the methane emissions from Russian natural gas transmission operations, to explain projects to reduce these emissions, and to characterize the role of emissions reduction within the context of current GHG policy. It draws on the most recent independent measurements at all parts of the Russian long distance transport system made by the Wuppertal Institute in 2003 and combines these results with the findings from the US Natural Gas STAR Program on GHG mitigation options and economics.With this background the paper concludes that the methane emissions from the Russian natural gas long distance network are approximately 0.6% of the natural gas delivered. Mitigating these emissions can create new revenue streams for the operator in the form of reduced costs, increased gas throughput and sales, and earned carbon credits. Specific emissions sources that have cost-effective mitigation solutions are also opportunities for outside investment for the Joint Implementation Kyoto Protocol flexibility mechanism or other carbon markets.  相似文献   
143.
Journal of Material Cycles and Waste Management - This study characterizes the municipal solid waste (MSW) accumulated for more than 25 years at Bhalswa dumpsite, Delhi, India. 50...  相似文献   
144.
Massive production of hydrogen by water decomposition triggered by a solar light active photocatalyst is a major objective in chemistry and a promising avenue to overcome the global energy crisis. The development of efficient, stable, economically viable and eco-friendly photocatalysts for hydrogen production is a challenging task. This article reviews the use of nanocomposite in three combinations: metal oxide–metal oxide semiconductor, metal–metal oxide semiconductor and metal chalcogenide–metal oxide core–shell nanostructures. These core–shell structures occur in two forms: a simple form where the photocatalyst is either in the core or the shell or in a more complex system where the core–shell structure comprises a co-catalyst deposited on a semiconducting material. We discuss the design, synthesis and development of semiconductor-based nanocomposite photocatalysts for hydrogen production. The major points are the role of catalytic active sites, the chemical nature of sacrificial agents, the effect of light sources, the variable light intensity and the energy efficiency calculation. For TiO2-based nanocomposites, the metal oxide or metal co-catalyst loading of 1.0–3.0 wt% was optimal. TiO2 nanotube–CuO hybrid nanocomposites produce 1,14,000 µmol h?1 \({\text{g}}^{ - 1}_{\text{cat}}\), whereas TiO2/Au nanocomposites display 1,60,000 µmol h?1 \({\text{g}}^{ - 1}_{\text{cat}}\). For core–shell catalysts, a shell thickness of 2–20 nm was found for the best activity, and its performance is as follows: (a) CdS–NiO system produces around 19,949 µmol h?1 \({\text{g}}^{ - 1}_{\text{cat}}\) and (b) CuO–Cr2O3 as co-catalyst immobilized on TiO2 system produces around 82,390 µmol h?1 \({\text{g}}^{ - 1}_{\text{cat}}\).  相似文献   
145.
锁磷剂联合好氧反硝化菌修复富营养化水体   总被引:1,自引:1,他引:0  
氮磷是造成水体富营养化的主要原因,单一治理方法常常难以同时有效去除氮磷.本文利用1株分离自富营养化水体的好氧反硝化菌株(AD-19)构建固定化菌膜,并与锁磷剂Phoslock®联合修复富营养化水体,研究了Phoslock®的控磷效能和反硝化菌的脱氮性能及二者联合作用时对富营养化水体的修复效果.结果表明,在投加比例为80(Phoslock®与PO43--P的质量比)的条件下,Phoslock®对模拟富营养化水体中PO43--P去除率可达95%以上,并能有效抑制底泥中磷的释放.好氧反硝化菌AD-19具有较好的异养硝化-好氧反硝化功能,在以NH4+-N或NO3--N为唯一氮源条件下生长良好并能去除97%以上的氮,经16S rDNA鉴定该菌株属于假单胞菌属(Pseudomonas sp.).利用湖泊模拟装置论证了Phoslock®联合固定化菌膜修复富营养化水体的可行性,进一步地,利用该技术对武汉市某公园内富营养化池塘进行修复治理,经过16 d的处理,氮磷等水质指标从劣Ⅴ类地表水提升至Ⅲ类,并持续稳定270 d以上,证明Phoslock®联合固定化菌膜可快速和有效地修复富营养化水体,并保持水质长期稳定.  相似文献   
146.
Environmental Science and Pollution Research - The application of pesticides enhances food production vastly, and it cannot be prevented; longer fresh produce is contaminated with...  相似文献   
147.
The process of designing a remedy for contaminated groundwater historically has not commonly included climate-future, hydrologic, and biogeochemical aquifer characteristics. From experience, the remedy design process also has not consistently nor directly integrated or projected future hydrologic and biogeochemical effects of the human-induced or developed environment—aka the anthropogenic influence—on potential remedy performance. The apparent practice of (1) not regularly assessing anthro-influenced hydrological (termed here as anthrohydrology) or biogeochemical characteristics (collectively hydrobiogeochemistry) of a site and (2) rarely accounting for future climatic shifts as design factors in remedy design may be due, in part, to the general practice-level view that groundwater remediation systems (whether in situ or ex situ) have seldom been anticipated to last more than a few years (or one or two decades at the most). Second, methods to reliably and quantitatively estimate site-specific, climate-future shifts in groundwater conditions using global and/or regional climate models and the resultant impacts on contaminant plume characteristics have not been readily available. The authors here suggest that while the concept of remedy design resilience and durability, within an envelope of climate change and anthropogenic influence, has been discussed in some technical circles as a component of “sustainable remediation,” we have found that direct application of these technical concepts in quantifiable terms remains rare. By incorporating the potential influence of future hydrobiogeochemical scenarios into remedy design, however, the design process could account for reasonable climate-induced influence on the groundwater system for a given site. These scenarios could then be applied within the remedy selection process to assess performance durability under potentially changing hydrologic, biological, and chemical conditions.  相似文献   
148.
Environmental Science and Pollution Research - Heritage structures are valuable monuments that describe the culture and tradition of the country. In today’s world, natural or artificial...  相似文献   
149.
Journal of Material Cycles and Waste Management - This research investigation has mainly focused on the development of cementless concrete, i.e., geopolymer concrete, along with the reutilization...  相似文献   
150.
Environmental Chemistry Letters - Non-biodegradable plastics are continually amassing landfills and oceans worldwide while creating severe environmental issues and hazards to animal and human...  相似文献   
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