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Carbon labelling of grocery products: public perceptions and potential emissions reductions 总被引:3,自引:0,他引:3
Public perceptions of a UK carbon labelling trial were assessed via three focus groups. The public found it very difficult to make sense of labelled emissions values without additional information. There was also little evidence of a willingness to use labels for product selection. There is a strong case for using carbon reduction labels to indicate a programme of on-going emissions reductions, rather than expecting consumers to incentivise emissions reductions by actively choosing the lower carbon variant of two or more products. The normalisation issues and emissions reduction potential of carbon labelling are discussed. 相似文献
784.
Evaluation of carbon stock variation in Northern Italian soils over the last 70 years 总被引:1,自引:0,他引:1
Carbon (C) sequestration in soils is gaining increasing acceptance as a means of reducing net carbon dioxide (CO2) emissions to the atmosphere. Numerous studies on the global carbon budget suggest that terrestrial ecosystems in the mid-latitudes
of the Northern Hemisphere act as a large carbon sink of atmospheric CO2. However, most of the soils of North America, Australia, New Zealand, South Africa and Eastern Europe lost a great part of
their organic carbon pool on conversion from natural to agricultural ecosystems during the explosion of pioneer agriculture,
and in Western Europe the adoption of modern agriculture after the Second World War led to a drastic reduction in soil organic
carbon content. The depletion of organic matter is often indicated as one of the main effects on soil, and the storage of
organic carbon in the soil is a means of improve the quality of soils and mitigating the effects of greenhouse gas emission.
The soil organic carbon in an area of Northern Italy over the last 70 years has been assessed In this study. The variation
of top soil organic carbon (SOC) ranged from −60.3 to +6.7%; the average reduction of SOC, caused by agriculture intensification,
was 39.3%. This process was not uniform, but related to trends in land use and agriculture change. For the area studied (1,394 km2) there was an estimated release of 5 Tg CO2-C to the atmosphere from the upper 30 cm of soil in the period 1935–1990. 相似文献
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Elevated CO2 can stimulate wetland carbon (C) and nitrogen (N) exports through gaseous and dissolved pathways, however, the consequent influences on the C and N pools are still not fully known. Therefore, we set up a free-air CO2 enrichment experiment in a paddy field in Eastern China. After five year fumigation, we studied C and N in the plant–water–soil system. The results showed: (1) elevated CO2 stimulated rice aboveground biomass and N accumulations by 19.1% and 12.5%, respectively. (2) Elevated CO2 significantly increased paddy soil TOC and TN contents by 12.5% and 15.5%, respectively in the 0–15 cm layer, and 22.7% and 26.0% in the 15–30 cm soil layer. (3) Averaged across the rice growing period, elevated CO2 greatly increased TOC and TN contents in the surface water by 7.6% and 11.4%, respectively. (4) The TOC/TN ratio and natural δ15N value in the surface soil showed a decreasing trend under elevated CO2. The above results indicate that elevated CO2 can benefit C and N accumulation in paddy fields. Given the similarity between the paddies and natural wetlands, our results also suggest a great potential for long-term C and N accumulation in natural wetlands under future climate patterns. 相似文献
788.
Cyanobacterial bloom dynamics in Lake Taihu 总被引:1,自引:0,他引:1
<正>Lake Taihu is the third largest freshwater lake in China and serves as an important drinking water source for the local populace;however,decades of excessive nutrient loading fueled by anthropogenic activities have resulted in hypertrophic conditions,promoting the annual formation of nuisance phytoplankton blooms(Chen et al.,2003;Duan et al.,2009) 相似文献
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To decrease the operating cost of flue gas purification technologies based on carbon-based materials, the adsorption and regeneration performance of low-price semi-coke and activated coke were compared for SO2 and NO removal in a simulated flue gas. The functional groups of the two adsorbents before and after regeneration were characterized by a Fourier transform infrared (FTIR) spectrometer, and were quantitatively assessed using temperature programmed desorption (TPD) coupled with FTIR and acid–base titration. The results show that semi-coke had higher adsorption capacity (16.2% for SO2 and 38.6% for NO) than activated coke because of its higher content of basic functional groups and lactones. After regeneration, the adsorption performance of semi-coke decreased because the number of active functional groups decreased and the micropores increased. Semi-coke had better regeneration performance than activated coke. Semi-coke had a larger SO2 recovery of 7.2% and smaller carbon consumption of 12% compared to activated coke. The semi-coke carbon-based adsorbent could be regenerated at lower temperatures to depress the carbon consumption, because the SO2 recovery was only reduced a small amount. 相似文献
790.
新常态下发展低碳经济已经成为主要趋势,碳金融将进入快速发展阶段,因此作为重要中介机构的商业银行面临着巨大的机遇和挑战,把握契机开拓碳金融业务发展新进程迫在眉睫。通过对我国商业银行碳金融业务发展现况及存在的系统性、机构性和业务性障碍的分析,结合新常态的经济背景,为我国商业银行发展碳金融业务提供了一些建议。 相似文献