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451.
中国碳排放问题成为世界关注的焦点问题。研究碳排放与经济增长、能源消费关系有助于实现2020年碳减排目标。选取2001~2009年碳排放与能源消费、经济增长数据,运用灰色关联分析模型,分别计算碳排放与能源消费、经济增长的灰色关联度。研究结果表明,无论是从折线的相似程度还是相对于始点变化速率的接近程度来看,碳排放曲线与能源消费曲线、经济增长曲线十分相似,说明碳排放与能源消费、经济增长之间存在紧密联系。  相似文献   
452.
生态足迹模型作为度量区域可持续发展程度的方法已用于多领域多层次的评价,也被越来越多的学者研究、分析、修正和质疑。文章在阅读该领域重要文献和报告的基础上,对国内外学者提出的各类生态足迹修正模型进行梳理,并聚焦于生态足迹与其他测度指标的结合以及其在战略环境评价中的应用,对生态足迹模型作为环境评估工具的潜力及其未来的研究方向提出个人的看法。  相似文献   
453.
Abstract

The increasing awareness of climate change has led organizations to demand a standard procedure to measure and communicate greenhouse gas (GHG) emissions linked to their products or services. The publicly available specification PAS 2050 has been developed in response to broad community and industry desire for a consistent method-carbon footprint for assessing the life cycle GHG emissions of goods and services. Specifically, this paper illustrates the implementation of carbon footprint for a baby stroller in accordance with PAS 2050. A fial value of 321 kg per one stroller including package was calculated. Moreover, the study led to identify raw materials production of the stroller as the main source of GHS emissions where efforts need to focus for emission reduction opportunities. This case study is hoped to be a starting point for organizations to benefit from the increasing application of carbon footprint assessment.  相似文献   
454.
Current carbon footprinting (CF) and life cycle assessment (LCA) methods do not treat recycled biogenic carbon adequately, because the calculation rules for recycled products and biogenic carbon stored in products are defined independently from each other. Therefore, an improved and consistent calculation rule for the CF of product systems containing both recycling processes and carbon stored in products is proposed. The methodological approach consists of the application of the same allocation principles for both greenhouse gas (GHG) releases and GHG removals: (1) explicit accounting of inputs (GHG removals) and outputs (GHG releases) of biogenic carbon flows instead of assuming carbon neutrality per se; (2) consistent application of allocation rules for environmental benefits and environmental burdens. It is shown that the different modelling approaches (e.g. polluter pays, conservative or partitioning) lead to different results in LCA and CF calculations, e.g. the GHG emissions of first life cycle of the product system calculated here range between ? 1.6 units in the polluter pays approach and 4 units in the conservative approach. It is shown that the currently common modelling is an average approach for primary biogenic material, a worst-case approach for recycled biogenic material and a best-case approach for disposed biogenic material. This paper proposes to improve the currently developed standards for CF by adding a requirement to the goal and scope definition phase that ensures the consistent and transparent documentation, how biogenic carbon removal credits are allocated between life cycles.  相似文献   
455.
● Diurnal patterns of CH4 and CO2 are clearly extracted using EEMD. ● CH4 and CO2 show mid-morning high and evening low patterns during sea breezes. ● Wind direction significantly modulates the diurnal variations in CH4 and CO2. Methane (CH4) and carbon dioxide (CO2) are the two most important greenhouse gases (GHGs). To examine the variation characteristics of CH4 and CO2 in the coastal South China Sea, atmospheric CH4 and CO2 measurements were performed in Bohe (BH), Guangdong, China, in summer 2021. By using an adaptive data analysis method, the diurnal patterns of CH4 and CO2 were clearly extracted and analysed in relation to the sea breeze (SB) and land breeze (LB), respectively. The average concentrations of CH4 and CO2 were 1876.91 ± 31.13 ppb and 407.99 ± 4.24 ppm during SB, and 1988.12 ± 109.92 ppb and 421.54 ± 14.89 ppm during LB, respectively. The values of CH4 and CO2 during SB basically coincided with the values and trends of marine background sites, showing that the BH station could serve as an ideal site for background GHG monitoring and dynamic analysis. The extracted diurnal variations in CH4 and CO2 showed sunrise high and sunset low patterns (with peaks at 5:00–7:00) during LB but mid-morning high and evening low patterns (with peaks at 9:00) during SB. The diurnal amplitude changes in both CH4 and CO2 during LB were almost two to three times those during SB. Wind direction significantly modulated the diurnal variations in CH4 and CO2. The results in this study provide a new way to examine the variations in GHGs on different timescales and can also help us gain a better understanding of GHG sources and distributions in the South China Sea.  相似文献   
456.
China has been committed to achieving carbon neutrality by 2060. China’s pledge of carbon neutrality will play an essential role in galvanising global climate action, which has been largely deferred by the Covid-19 pandemic. China’s carbon neutrality could reduce global warming by approximately 0.2–0.3 °C and save around 1.8 million people from premature death due to air pollution. Along with domestic benefits, China’s pledge of carbon neutrality is a “game-changer” for global climate action and can inspire other large carbon emitters to contribute actively to mitigate carbon emissions, particularly countries along the Belt and Road Initiative (BRI) routes. In order to achieve carbon neutrality by 2060, it is necessary to decarbonise all sectors in China, including energy, industry, transportation, construction, and agriculture. However, this transition will be very challenging, because major technological breakthroughs and large-scale investments are required. Strong policies and implementation plans are essential, including sustainable demand, decarbonizing electricity, electrification, fuel switching, and negative emissions. In particular, if China can peak carbon emissions earlier, it can lower the costs of the carbon neutral transition and make it easier to do so over a longer time horizon. China’s pledge of carbon neutrality by 2060 and recent pledges at the 26th UN Climate Change Conference of the Parties (COP26) are significant contributions and critical steps for global climate action. However, countries worldwide need to achieve carbon neutrality to keep the global temperature from growing beyond the level that will cause catastrophic damages globally.  相似文献   
457.
Various anaerobic processes have been explored for the energy-efficient treatment of municipal wastewater. However, dissolved methane in anaerobic effluent appears to be a barrier towards the energy and carbon neutrality of wastewater treatment. Although several dissolved methane recovery methods have been developed, their engineering feasibility and economic viability have not yet been assessed in a holistic manner. In this perspective, we thus intend to offer additional insights into the cost-benefit of dissolved methane recovery against its emission.  相似文献   
458.
As ecovillages present themselves as models of low-carbon living measuring the Ecological Footprint (EF) of an ecovillage serves both to validate that claim and to examine the component features of how the EF is achieved. This article examines the first measurement of the EF of Ireland’s only ecovillage, situated in the village of Cloughjordan in county Tipperary. The objectives here were to measure the EF of the ecovillage at the household scale and then to use the EF to provide meaningful feedback and reflective learning on human carbon intensity to the ecovillage residents. Various methods were applied in this action research to achieve high levels of engagement and potent communication of what could be learnt from the EF. This article places a particular focus on the necessary adaptation of an original EF method, on how it was implemented in the ecovillage, on the results obtained and on how these were communicated to the residents. The bottom-up component EF method samples consumption data at source and in so doing appoints consumption reflection and responsibility in ways the more remote compound method can not. The strategic combination of this specific quality with co-creation method aims to meaningfully engage and motivate a settlement to reduce its carbon intensity. According to the methodology, the ecovillage residents overshoot the fair earth share by 10% needing 1.1 planets to sustain their lifestyles. It is planned that subsequent to this intervention future measurements will show whether the overshoot has reduced.  相似文献   
459.
面对三峡库区日益突出的环境问题,研究人员做出众多研究,但对库区河流碳的赋存形态及其影响研究报道较少.在2019年春夏两季通过现场采样室内分析的方式测定了各形态碳含量,重点分析了澎溪河流域水中碳素的分布特征.结果 表明:澎溪河流域碳含量总体呈现上游低下游高,春季低夏季高的分布特点,两季TOC均值均超过水体富营养化标准达1...  相似文献   
460.
The digital elevation model data from traditional stereo photogrammetric methods are inadequate in providing accurate vertical parameters to feed hydrologic models for low‐lying, extremely flat areas. High‐resolution light detection and ranging (LiDAR) data provide the robust capability of capturing small variations in low‐relief playa wetlands. The Rainwater Basin in south‐central Nebraska includes a complex of seasonally shallow playa wetlands that attract millions of migratory waterfowl every spring and fall. This research focuses on the development of a procedure with applicable protocols to produce LiDAR‐derived three‐dimensional wetland maps and to extract the critical surface parameters (i.e., watershed boundaries, flow direction, flow accumulation, and drainage lines) for playa wetlands. The topo‐hydrologic conditions of playa wetlands were evaluated at the watershed level. The results show that in the Rainwater Basin, 70.7% of the historic hydric soil footprints identified in the Soil Survey Geographic (SSURGO) database were not functioning as topographically depressional wetlands. This finding was confirmed by a recent five‐year Annual Habit Survey showing that 69.8% of the historic hydric soil footprints did not function during the spring migratory bird seasons between 2004 and 2009. The majority of playa wetlands' topographic conditions have been substantially changed and the SSURGO data cannot fully reflect current topographic reality in the Rainwater Basin.  相似文献   
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