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411.
412.
Many rural communities in British Columbia (western Canada) are at risk from wildfire. This risk will increase over time as a result of climate change because of higher average temperatures, longer growing seasons, and more intense droughts. On the other hand, these communities are also faced with rising fuel costs and a growing demand for heat as suburban population increases. The fact these communities are surrounded by forests presents an opportunity to combine community wildfire risk abatement with bioenergy development. Additional co-benefits include: (1) reduced community energy expenditures; (2) the creation of local jobs; (3) climate change mitigation; and (4) increased community energy security. Here, we present results from three pilot rural communities (Burns Lake, Invermere, and Sicamous, all of them in British Columbia) designed to evaluate the feasibility of wildfire risk abatement in conjunction with bioenergy production. Maps were created showing each community's forest–urban interface area with quantified estimates of its sustainable woody biomass resource potential under different management scenarios while monitoring ecosystem and soil health. The results and experience gained through this work has been synthesized in a calculator tool to help other communities make their own screening-level assessments. This calculator is a freely available on-line tool: FIRST Heat. 相似文献
413.
The Packaging and Packaging Waste Directive has had an undeniable impact on waste management throughout the European Union. Whereas recycling and recovery targets are the same, member states still enjoy a considerable degree of freedom with respect to the practical organization and management strategies adopted. Nevertheless, in all cases, the industry (which brings packaging material onto the market) should be responsible for the costs associated with packaging waste recycling/recovery (following the extended producer responsibility principle). The current paper compares and contrasts the institutional frameworks and financial costs and benefits of waste management operators for Belgium and Portugal. The unit costs of selective collection and sorting of packaging waste are provided for both countries. In Belgium, the costs of recycling seem to be fully supported by the industry (through Fost Plus, the national Green Dot agency). In Portugal the fairness of the recycling system depends on the perspective adopted (economic or strictly financial). Adopting a strictly financial perspective, it seems that Sociedade Ponto Verde (SPV, the Portuguese Green Dot agency) should increase the transfers to local authorities. However, the conclusions differ for this country if the avoided costs with refuse collection and other treatment are taken into account. 相似文献
414.
微生物燃料电池在降解污染物的同时能将污染物中的化学能转化为电能。研究微生物燃料电池是对污水处理过程中回收环境友好能源的多学科交叉探索,可以为我国有效解决能源与环境问题提供新的技术途径。水生植物在微生物燃料电池研究中已得到了应用,显示出了良好的污水净化效果和生物产电特性。目前利用水生植物构建的微生物燃料电池,一类是将高等植物根区作为电池的阳极系统,目的是利用根区分泌物解决MFC的燃料问题;另一类是直接将低等水生植物藻类构建生物阴极型微生物燃料电池,其实质是利用藻类光合作用产氧构建好氧型生物阴极微生物燃料电池而还原CO2。文章对水生植物在微生物燃料中的作用机制、调控措施、运行条件、工艺参数等方面的研究现状进行了综合分析,也提出了需要深入研究的方向。 相似文献
415.
Recently there has been a surge in the number of green roofs and façades (vegetation on the roofs & walls of a building) installed in the UK, with advocation of their use by policy-makers and claims that they are aesthetically pleasing and promote restoration. But these claims rely on generalisations from different landscapes, raising concerns about validity. The present study examined whether houses with vegetation would be more preferred than those without, be perceived as more beautiful and restorative, and have a more positive affective quality. Differences between types of building-integrated vegetation were also examined. Two studies were conducted: an online survey in which participants (N = 188) rated photographs of houses with and without vegetation on each of these measures, and interviews (N = 8) which examined preference and installation concerns. Results showed that houses with (some types of) building-integrated vegetation were significantly more preferred, beautiful, restorative, and had a more positive affective quality than those without. The ivy façade and meadow roof rated highest on each. These findings are consistent with other areas of landscape research and the claims of those in the industry, and suggest that building-integrated vegetation would be a valuable addition to the urban environment. 相似文献
416.
The power sector in Thailand is the largest contributor to CO2 emissions. There is high potential to mitigate CO2 emission via alternative power generating plants. Alternative plants considered in this study include nuclear plants, integrated gasification combined cycle plants, biomass-based plants and supercritical thermal power plants. The biomass-based plants considered here are fueled with four types of biomass; paddy husk, municipal solid waste (MSW), fuel wood and corncob. The methodology for the optimal expansion plan of the power generating system over the planning horizon is based on the least-cost approach. The results from the least-cost planning analyses show that the nuclear alternative has the highest potential to mitigate not only CO2 but also other airborne emissions. Moreover, the nuclear option is the most effective abatement strategy for CO2 reduction due to its negative incremental cost of CO2 reduction. 相似文献
417.
418.
Wen-Juan Pan Can Xiong Qiu-Ping Wu Jin-Xia Liu Hong-Mei Liao Wei Chen Yong-Sheng Liu Lei Zheng 《Chemosphere》2013
Bisphenol A (BPA) is a well-known environmental toxic substance, which exerts unfavorable effects through endocrine disruptor (ER)-dependent and ER-independent mechanisms to threaten ecological systems seriously. BPA may also interact with other environmental factors, such as light and heavy metals, to have a synergetic effect in plants. However, there is little data concerning the toxic effect of BPA on the primary producers-plants and its possible interaction with light-dependent response. Here, the effects of BPA on germination, fresh weight, tap root length, and leaf differentiation were studied in Arabidopsis thaliana under different parts of light spectrum (dark, red, yellow, green, blue, and white light). Our results showed that low-dose BPA (1.0, 5.0 μM) caused an increase in the fresh weight, the tap root length and the lateral root formation of A. thaliana seedlings, while high-dose BPA (10.0, 25.0 μM) show an inhibition effect in a dose-dependent manner. Unlike karrikins, the effects of BPA on germination fresh weight and tap roots length under various light conditions are similar, which imply that BPA has no notable role in priming light response in germination and early seedling growth in A. thaliana. Meanwhile, BPA exposure influences the differentiation of A. thaliana leaf blade significantly in a light-dependent manner with little to no effect in dark and clear effect under red illumination. 相似文献
419.
420.
绿色设计是现代制造业可持续发展的模式 总被引:2,自引:0,他引:2
绿色设计是一种面向可持续发展的新发展的新制造模式,本文叙述绿色设计的基本思想及其关键技术,讨论绿色设计的评价体系和基本方法,并提出推行绿色技术的主要措施。 相似文献