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241.
242.
CO2是《京都议定书》要求减排的6种温室气体之一,《京都议定书》还确立了有助于发展中国家获得资金和先进技术的清洁发展机制(CDM)。本文结合实际工程案例,介绍了合成氨副产CO2气的回收和利用方法,为我国氮肥行业申请CDM项目资助,回收利用CO2,减少CO2排放提供技术参考。 相似文献
243.
Kenneth T. Gillingham Steven J. Smith Ronald D. Sands 《Mitigation and Adaptation Strategies for Global Change》2008,13(7):675-701
In the coming century, modern bioenergy crops have the potential to play a crucial role in the global energy mix, especially
under policies to reduce carbon dioxide emissions as proposed by many in the international community. Previous studies have
not fully addressed many of the dynamic interactions and effects of a policy-induced expansion of bioenergy crop production,
particularly on crop yields and human food demand. This study combines an updated agriculture and land use (AgLU) model with
a well-developed energy-economic model to provide an analysis of the effects of bioenergy crops on energy, agricultural and
land use systems. The results indicate that carbon dioxide mitigation policies can stimulate a large production of bioenergy
crops, dependent on the level of the policy. This production of bioenergy crops can lead to several impacts on the agriculture
and land use system: decreases in forestland and unmanaged land, decreases in the average yield of food crops, increases in
the prices of food crops, and decreases in the level of human demand of calories.
相似文献
Steven J. Smith (Corresponding author)Email: |
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Carbon neutral Biggar: calculating the community carbon footprint and renewable energy options for footprint reduction 总被引:2,自引:0,他引:2
The objective of this research was to develop a community carbon footprint model that could be used to assess the size and
major components of a community’s carbon dioxide (CO2) emissions. The town of Biggar aims to become Scotland’s first carbon neutral town. As expected for this rural community,
car transport accounted for nearly half of the CO2 emissions, with natural gas and electricity consumption resulting in a further 24% and 12% of total emissions, respectively,
and air travel being the last major component at 10% of emissions. An assessment was also made of the wind and solar resources
of the town. One large wind turbine would provide the town’s electricity, while three to four turbines would be needed to
offset all CO2 emissions. In contrast, offsetting by tree planting would require in the region of 2,000 ha of trees.
相似文献
R. J. BarthelmieEmail: |
246.
为了解南京市溧水区大气挥发性有机物(VOCs)的组分、来源及其对臭氧的贡献,2021年对区域内VOCs开展了为期1 a的走航监测,进行数据分析.结果表明,溧水区ρ(TVOC)年均值为223.45μg·m-3,其中ρ(烷烃)为49.45μg·m-3(占比22.13%),ρ[含氧(氮)VOCs]为50.63μg·m-3(占比22.66%),ρ(卤代烃)为64.73μg·m-3(占比28.95%),ρ(芳香烃)为35.46μg·m-3(占比15.87%),ρ(烯烃)为18.26μg·m-3(占比8.19%),其他为4.9μg·m-3(占比2.2%).夏季的ρ(TVOC)平均值较高,为263.75μg·m-3,冬季较低,为187.2μg·m-3,春季为246.11μg·m-3,秋季为204.77μg·m-3.日均TVOC浓度,在09:00~10:00和14... 相似文献
247.
In the context of the ongoing climate change discussions the importance of peatlands as carbon stores is increasingly recognised in the public. Drainage, deforestation and peat fires are the main reasons for the release of huge amounts of carbon from peatlands. Successful restoration of degraded tropical peatlands is of high interest due to their huge carbon store and sequestration potential. The blocking of drainage canals by dam building has become one of the most important measures to restore the hydrology and the ecological function of the peat domes. This study investigates the capability of using multitemporal radar remote sensing imagery for monitoring the hydrological effects of these measures. The study area is the former Mega Rice Project area in Central Kalimantan, Indonesia, where peat drainage and forest degradation is especially intense. Restoration measures started in July 2004 by building 30 large dams until June 2008. We applied change detection analysis with more than 80 ENVISAT ASAR and ALOS PALSAR images, acquired between 2004 and 2009. Radar signal increases of up to 1.36 dB show that high frequency multitemporal radar satellite imagery can be used to detect an increase in peat soil moisture after dam construction, especially in deforested areas with a high density of dams. Furthermore, a strong correlation between cross-polarised radar backscatter coefficients and groundwater levels above -50 cm was found. Monitoring peatland rewetting and quantifying groundwater level variations is important information for vegetation re-establishment, fire hazard warning and making carbon emission mitigation tradable under the voluntary carbon market or REDD (Reducing Emissions from Deforestation and Degradation) mechanism. 相似文献
248.
Identifying priority areas for ecosystem service management in South African grasslands 总被引:2,自引:0,他引:2
Grasslands provide many ecosystem services required to support human well-being and are home to a diverse fauna and flora. Degradation of grasslands due to agriculture and other forms of land use threaten biodiversity and ecosystem services. Various efforts are underway around the world to stem these declines. The Grassland Programme in South Africa is one such initiative and is aimed at safeguarding both biodiversity and ecosystem services. As part of this developing programme, we identified spatial priority areas for ecosystem services, tested the effect of different target levels of ecosystem services used to identify priority areas, and evaluated whether biodiversity priority areas can be aligned with those for ecosystem services. We mapped five ecosystem services (below ground carbon storage, surface water supply, water flow regulation, soil accumulation and soil retention) and identified priority areas for individual ecosystem services and for all five services at the scale of quaternary catchments. Planning for individual ecosystem services showed that, depending on the ecosystem service of interest, between 4% and 13% of the grassland biome was required to conserve at least 40% of the soil and water services. Thirty-four percent of the biome was needed to conserve 40% of the carbon service in the grassland. Priority areas identified for five ecosystem services under three target levels (20%, 40%, 60% of the total amount) showed that between 17% and 56% of the grassland biome was needed to conserve these ecosystem services. There was moderate to high overlap between priority areas selected for ecosystem services and already-identified terrestrial and freshwater biodiversity priority areas. This level of overlap coupled with low irreplaceability values obtained when planning for individual ecosystem services makes it possible to combine biodiversity and ecosystem services in one plan using systematic conservation planning. 相似文献
249.
Degradation of carbon tetrachloride (CT) by microscale zero-valent iron (ZVI) was investigated in batch systems with or without organic ligands (ethylenediaminetetraacetic acid (EDTA), citric acid, tartaric acid, malic acid and oxalic acid) at pHs from 3.5 to 7.5. The results demonstrated that at 25°C, the dechlorination of CT by microscale ZVI is slow in the absence of organic ligands, with a pseudo-first-order rate constant of 0.0217 h(-1) at pH 3.5 and being further dropped to 0.0052 h(-1) at pH 7.5. However, addition of organic ligands significantly enhanced the rates and the extents of CT removal, as indicated by the rate constant increases of 39, 31, 32, 28 and 18 times in the presence of EDTA, citric acid, tartaric acid, malic acid and oxalic acid, respectively, at pH 3.5 and 25°C. The effect of EDTA was most significant; the dechlorination of CT at an initial concentration of 20 mg l(-1) increased from 16.3% (no ligands) to 89.1% (with EDTA) at the end of 8h reaction. The enhanced CT degradation in the presence of organic ligands was primarily attributed to the elimination of a surface passivation layer of Fe(III) (hydr)oxides on the microscale ZVI through chelating of organic ligands with Fe(III), which maintained the exposure of active sites on ZVI surface to CT. 相似文献
250.