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311.
312.
Veronika Dornburg Gregg Marland 《Mitigation and Adaptation Strategies for Global Change》2008,13(3):211-217
Kirschbaum (Mitig Adapt Strat Glob Change 11:1151–1164, 2006) explores the climatic impact over time of temporarily sequestering carbon from the atmosphere. He concludes that temporary
storage of carbon in the terrestrial biosphere “achieves effectively no climate-change mitigation”. His strongly worded statement
begs for a response. This paper argues that Kirschbaum’s conclusion is an artifact of the specific perspective of his analysis
and his choice of a definition for climate-change impact. Even temporary sinks put us on a lower path for climate change,
a path that will not otherwise be accessible. For carbon sinks in the terrestrial biosphere, we argue that sooner is better
and longer is better, but even known temporary sinks have value.
相似文献
Gregg Marland (Corresponding author)Email: |
313.
G. J. Nabuurs I. J. J. van den Wyngaert W. Daamen H. Kramer P. Kuikman 《Mitigation and Adaptation Strategies for Global Change》2008,13(3):267-282
A full account for carbon dioxide (CO2) and other greenhouse gas balance is presented for the Dutch forest and nature areas for 1990–2002 at a Tier 2.5 level. The
paper outlines how complex guidelines can be turned into a practical system, appropriate for a small country, making use of
the best knowledge and data available. The net total sink of all processes of the forest and other nature terrains balance
is very stable through time around an average of 1.74 million tonnes of CO2 per year. The sink is to a large extent determined by the growth of forest remaining forest, and the harvest taking place
in there. Newly added processes in this new National System are significant as well, but they compensate each other. The sources
from deforestation and nitrous oxide (N2O) emissions (around 900 ktonne CO2) are for two thirds compensated by the sinks from afforestation, dead wood, soil C changes due to land use changes, and trees
outside the forest. The land use changes between 1990 and 2000 showed that The Netherlands has an annual deforestation of
2504 ha (0.7% of the forest area) and an afforestation of 3124 ha. Deforestation led in total over the 13 years of 1990–2002
to an emission of 11.2 million tonne CO2 compensated by only 1.9 million tonne CO2 due to afforestation.
相似文献
G. J. NabuursEmail: |
314.
Natural chemical weathering of silicate rocks is a significant sink for soil and atmospheric CO2. Previous work suggested that natural chemical weathering may be stimulated by applying finely ground silicate rocks to agricultural
areas or forests [stimulated weathering (SW)]. However, it remained unknown if this technique is practical to sequester globally
significant amounts of CO2 under realistic conditions. Applying first estimates of “normal treatment” amounts from a literature review, we report here
a theoretical global maximum potential of 65 106 t sequestered C a−1 if SW would be applied homogenously on all agricultural and forested areas of the world. This is equivalent to 0.9% of anthropogenic
CO2 emissions (reference period 2000–2005). First, however, the assumed application of SW on most of the considered areas is
not economically feasible because of logistic issues, and second the net-CO2 sequestration is expected to amount to only a fraction of consumed CO2 due to the energy demand of the application itself (currently ~11%). Unless progress in application procedures is provided,
the recent realistic maximum net-CO2-consumption potential is expected to be much smaller than 0.1% of anthropogenic emissions, and the SW would thus not be one
of the key techniques to reduce atmospheric CO2 concentration. However, literature suggests that for some agricultural areas (croplands) and specifically for rice production
areas in humid climates, this SW may be a feasible tool to support international efforts to sequester CO2. SW may be cost effective for those areas if linked to the CO2-emission certificate trade in the future, and increases in crop production are taken into account. 相似文献
315.
温室效应和全球变暖已经引起了世界各国的普遍关注,减少二氧化碳等温室气体的排放已成为大势所趋。开发和利用煤层气不仅可避免资源的浪费,还可减少温室气体排放、改善大气环境。本文结合重庆市松藻矿区蝶层气开发利用情况,分析评价了松藻矿区煤层气利用对温室气体减排的贡献。结果表明,煤层气利用具有显著的环境效益和经济效益。 相似文献
316.
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
317.
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: |
318.
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
319.
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
320.