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381.
M. C. Portillo E. Porca S. Cuezva J. C. Cañaveras S. Sanchez-Moral J. M. Gonzalez 《Die Naturwissenschaften》2009,96(9):1035-1042
Bacteria thriving in underground systems, such as karsts, adapt to use a variety of nutrients. Most of these nutrients derive
from superficial processes. This study shows that bacteria are able to differentially induce carbonate precipitation or dissolution
depending on the availability of nutrients for growth. Different bacterial strains isolated from caves, representing the most
common components of these microbial communities, were cultured with different carbon and nitrogen sources (e.g., acetate,
glucose, peptone, humic acids) and induced changes in pH were measured during growth. Carbonate can either precipitate or
dissolve during bacterial growth. The induction of carbonate precipitates or their dissolution as a function of consumption
of specific carbon sources revealed the existence of an active nutrient cycling process in karsts and links nutrients and
environmental conditions to the existence of a highly significant carbon sink in subterraneous environments. 相似文献
382.
Development of regional climate mitigation baseline for a dominant agro-ecological zone of Karnataka,India 总被引:1,自引:0,他引:1
P. Sudha D. Subhashree H. Khan G. T. Hedge I. K. Murthy V. Shreedhara N. H. Ravindranath 《Mitigation and Adaptation Strategies for Global Change》2007,12(6):1051-1075
Setting a baseline for carbon stock changes in forest and land use sector mitigation projects is an essential step for assessing
additionality of the project. There are two approaches for setting baselines namely, project-specific and regional baseline.
This paper presents the methodology adopted for estimating the land available for mitigation, for developing a regional baseline,
transaction cost involved and a comparison of project-specific and regional baseline. The study showed that it is possible
to estimate the potential land and its suitability for afforestation and reforestation mitigation projects, using existing
maps and data, in the dry zone of Karnataka, southern India. The study adopted a three-step approach for developing a regional
baseline, namely: (i) identification of likely baseline options for land use, (ii) estimation of baseline rates of land-use
change, and (iii) quantification of baseline carbon profile over time. The analysis showed that carbon stock estimates made
for wastelands and fallow lands for project-specific as well as the regional baseline are comparable. The ratio of wasteland
Carbon stocks of a project to regional baseline is 1.02, and that of fallow lands in the project to regional baseline is 0.97.
The cost of conducting field studies for determination of regional baseline is about a quarter of the cost of developing a
project-specific baseline on a per hectare basis. The study has shown the reliability, feasibility and cost-effectiveness
of adopting regional baseline for forestry sector mitigation projects.
相似文献
N. H. RavindranathEmail: |
383.
Controls over soil microbial biomass responses to carbon amendments in agricultural systems: A meta-analysis 总被引:1,自引:0,他引:1
Cynthia Kallenbach 《Agriculture, ecosystems & environment》2011,144(1):241-252
Soil microbial biomass (MB) facilitates key ecosystem functions such as soil aggregation and nutrient cycling and makes a substantial contribution to soil organic matter. While agricultural conversion drastically reduces MB, the use of organic amendments is an effective way to rebuild depleted MB. Yet, little is known about broad-scale, global controls over MB responses to organic inputs. We used a meta-analysis to identify the degree to which soil properties, agricultural management, and geographic location regulate MB response (carbon, Cmic; nitrogen, Nmic; and C:N ratio, C:Nmic) to animal manure-based inputs relative to inorganic fertilizers. We show that organic amendments increased Cmic by 36% and Nmic by 27% across all observations. The chemistry of amendments and their application rates were the strongest regulators of Cmic but edaphic properties were also important. C:Nmic averaged 8.6 and was not influenced by organic amendments under any conditions, providing evidence that the physiological requirements of microbes, rather than management or environmental factors, constrain their elemental stoichiometry. Our study indicates that even small quantities of organic amendments can be used to rapidly restore MB across a range of cropping systems but specific responses depend upon the type and rate of inputs as well soil characteristics. 相似文献
384.
Integrating carbon footprint into supply chain management: the case of Hyundai Motor Company (HMC) in the automobile industry 总被引:5,自引:0,他引:5
Ki-Hoon LeeAuthor Vitae 《Journal of Cleaner Production》2011,19(11):1216-1223
The purpose of this paper is to improve our understanding of carbon footprint within the context of automobile supply chain management. The case study approach is employed as a research method. Primary data were collected through site visits and extensive interviews with HMC’s corporate and plant management. First, identification and measurement of direct and indirect carbon footprint is critical for mitigating supply chain risks. Second, setting the system boundary of measurement is another important issue to integrate the issue of carbon footprint into supply chain management. Third, developing a map of product carbon footprint facilitates identification and measurement of carbon emissions across the supply chain. Companies today operate in a carbon-constrained world. In particular, the automobile industry is under pressure to take a close look at its product carbon footprint. Managing the downstream consequences of the use of its products and inputs from upstream suppliers is critical for developing carbon risk-mitigated supply chain management. This paper is of benefit to academics and managers by providing a new way to integrate carbon emissions in supply chain management. Since climate change and carbon footprint present challenges to many industries, increasing our understanding of how to integrate carbon footprint in supply chain management is necessary, but has seen little research in the automobile industry. 相似文献
385.
386.
本文介绍了四氯化碳显色目视比色法测定溶解氧方法的研究过程,通过时分析方法中,标准试剂的选择,萃取剂的选择,碘化钾(K1)用量的选择,及稳定性实验,消除干扰实验,环境温度实验,方法准确度及精密度实验,表明此方法快速、准确、分析结果直观、适合应急监测。 相似文献
387.
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
388.
Yangyan Cheng Ye Shan Yuhuan Xue Yujiao Zhu Xinfeng Wang Likun Xue Yanguang Liu Fangli Qiao Min Zhang 《Frontiers of Environmental Science & Engineering》2022,16(11):139
389.
Hong Yang Xianjin Huang Jianlin Hu Julian R. Thompson Roger J. Flower 《Frontiers of Environmental Science & Engineering》2022,16(8):111
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
390.
Xiaoyuan Zhang Jun Gu Shujuan Meng Yu Liu 《Frontiers of Environmental Science & Engineering》2022,16(4):54
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