Measurements of greenhouse gases CO2, CH4, and N2O were made by static chamber-gas chromatograph in Inner Mongolia. Results indicate that with growing seasons, the daily variation patterns of emission/uptake of greenh...Measurements of greenhouse gases CO2, CH4, and N2O were made by static chamber-gas chromatograph in Inner Mongolia. Results indicate that with growing seasons, the daily variation patterns of emission/uptake of greenhouse gases differ greatly in the prairie ecosystem. The peak of seasonal emission/uptake of three greenhouse gases occurs at the melting period in spring when soil moisture is high and rainfall is rich. The daily emissions of CO2 from steppe vegetation in growing seasons are low during the daytime and high at night. Higher temperatures are advantageous to emission of CO2, as aboveground biomass determines the amount of CO2 photosynthetic uptake. The key factors that influence the daily variation patterns of CH4 uptake and N2O emission in semiarid grassland are soil moisture and the oxygen supplying condition, while the changes in daily temperature mainly affect the range of daily variations. The seasonal changes of N2O emission are positively related to seasonal change in soil moisture. Free grazing reduces the daily mean deviation of exchange rates of CO2, N2O, and CH4, but it decreases the amount of annual emission/uptake of N2O and CH4 yet it increases the annual emission of CO2.展开更多
China is playing an increasing role in global climate change mitigation,and local authorities need more city-specifc information on the emissions trends and patterns when designing low-carbon policies.This study provi...China is playing an increasing role in global climate change mitigation,and local authorities need more city-specifc information on the emissions trends and patterns when designing low-carbon policies.This study provides the most comprehensive COemission inventories of 287 Chinese cities from 2001 to2019.The emission inventories are compiled for 47 economic sectors and include energy-related emissions for 17 types of fossil fuels and process-related emissions from cement production.We further investigate the state of the emission peak in each city and reveal hidden driving forces.The results show that38 cities have proactively peaked their emissions for at least fve years and another 21 cities also have emission decline,but passively.The 38 proactively peaked cities achieved emission decline mainly by effciency improvements and structural changes in energy use,while the 21 passively emission declined cities reduced emissions at the cost of economic recession or population loss.We propose that those passively emission declined cities need to face up to the reasons that caused the emission to decline,and fully exploit the opportunities provided by industrial innovation and green investment brought by low-carbon targets to achieve economic recovery and carbon mitigation goals.Proactively peaked cities need to seek strategies to maintain the downward trend in emissions and avoid an emission rebound and thus provide successful models for cities with still growing emissions to achieve an emission peak.展开更多
Household consumption is one of the important factors that induce COL emission. Based on input-output model, this article calculated the intensity of CO2 emission of different income groups and seven provinces in Chin...Household consumption is one of the important factors that induce COL emission. Based on input-output model, this article calculated the intensity of CO2 emission of different income groups and seven provinces in China, and then estimated total CO2 emission induced by urban household consumption from 1995 to 2004 in China based on statistic data of household living expenditure. The results show that CO2 emission per capita induced by household consumption had increased from 1583 to 2498 kg CO2 during 1995-2004. The ratio of consumption-induced CO2 emission to total CO2 emission had risen from 19% to 30% in the past decade. Indirect CO2 emission accounted for an important part of the consumption-induced emission, the ratio of indirect emission to consumption-induced emission had risen from 69% to 79% during the same period. A significant difference in consumption-induced CO2 emission across different income groups and different regions has been observed. COs emission per capita of higher income groups and developed regions increased faster than that of lower income groups and developing regions. Changing lifestyle has driven significant increase in CO2 emission. Especially, increases in private transport expenditure （for example, vehicle expenditure） and house building expenditure are key driving factors of growth in consumption-induced COL emission. There are big differences in the amount of CO2 emission induced by change in lifestyle across different income groups and provinces. It can be expected that lower income households and developing regions will increase consumption to improve their livings with income growth in the future, which may induce much more CO2 emission. A reasonable level of CO2 emission is necessary to satisfy human needs and to improve living standard, but a noticeable fact is that CO2 emission per capita induced by household consumption in developed areas of China had reached a quite high level. Adjustment in lifestyle towards a low-carbon society is in urgent need.展开更多
基金This work was supported bythe grant of the Knowledge Innovation Program of Chi-nese Academy of Sciences(approved # KZCX1SW-01).The authors would like to thank Dr.DU Rui, Wang Yan-fen,and Professor Zhang Wen,Wang Gengchen,and WangMingxing for t
文摘Measurements of greenhouse gases CO2, CH4, and N2O were made by static chamber-gas chromatograph in Inner Mongolia. Results indicate that with growing seasons, the daily variation patterns of emission/uptake of greenhouse gases differ greatly in the prairie ecosystem. The peak of seasonal emission/uptake of three greenhouse gases occurs at the melting period in spring when soil moisture is high and rainfall is rich. The daily emissions of CO2 from steppe vegetation in growing seasons are low during the daytime and high at night. Higher temperatures are advantageous to emission of CO2, as aboveground biomass determines the amount of CO2 photosynthetic uptake. The key factors that influence the daily variation patterns of CH4 uptake and N2O emission in semiarid grassland are soil moisture and the oxygen supplying condition, while the changes in daily temperature mainly affect the range of daily variations. The seasonal changes of N2O emission are positively related to seasonal change in soil moisture. Free grazing reduces the daily mean deviation of exchange rates of CO2, N2O, and CH4, but it decreases the amount of annual emission/uptake of N2O and CH4 yet it increases the annual emission of CO2.
基金supported by the National Natural Science Foundation of China(72140001 and 41921005)Shandong Provincial Science Fund for Excellent Youth Scholars(ZR2021YQ27)+1 种基金the National Social Science Fund of China(21ZDA065)the Natural Environment Research Council(2021GRIP02COP-AQ)。
文摘China is playing an increasing role in global climate change mitigation,and local authorities need more city-specifc information on the emissions trends and patterns when designing low-carbon policies.This study provides the most comprehensive COemission inventories of 287 Chinese cities from 2001 to2019.The emission inventories are compiled for 47 economic sectors and include energy-related emissions for 17 types of fossil fuels and process-related emissions from cement production.We further investigate the state of the emission peak in each city and reveal hidden driving forces.The results show that38 cities have proactively peaked their emissions for at least fve years and another 21 cities also have emission decline,but passively.The 38 proactively peaked cities achieved emission decline mainly by effciency improvements and structural changes in energy use,while the 21 passively emission declined cities reduced emissions at the cost of economic recession or population loss.We propose that those passively emission declined cities need to face up to the reasons that caused the emission to decline,and fully exploit the opportunities provided by industrial innovation and green investment brought by low-carbon targets to achieve economic recovery and carbon mitigation goals.Proactively peaked cities need to seek strategies to maintain the downward trend in emissions and avoid an emission rebound and thus provide successful models for cities with still growing emissions to achieve an emission peak.
文摘Household consumption is one of the important factors that induce COL emission. Based on input-output model, this article calculated the intensity of CO2 emission of different income groups and seven provinces in China, and then estimated total CO2 emission induced by urban household consumption from 1995 to 2004 in China based on statistic data of household living expenditure. The results show that CO2 emission per capita induced by household consumption had increased from 1583 to 2498 kg CO2 during 1995-2004. The ratio of consumption-induced CO2 emission to total CO2 emission had risen from 19% to 30% in the past decade. Indirect CO2 emission accounted for an important part of the consumption-induced emission, the ratio of indirect emission to consumption-induced emission had risen from 69% to 79% during the same period. A significant difference in consumption-induced CO2 emission across different income groups and different regions has been observed. COs emission per capita of higher income groups and developed regions increased faster than that of lower income groups and developing regions. Changing lifestyle has driven significant increase in CO2 emission. Especially, increases in private transport expenditure （for example, vehicle expenditure） and house building expenditure are key driving factors of growth in consumption-induced COL emission. There are big differences in the amount of CO2 emission induced by change in lifestyle across different income groups and provinces. It can be expected that lower income households and developing regions will increase consumption to improve their livings with income growth in the future, which may induce much more CO2 emission. A reasonable level of CO2 emission is necessary to satisfy human needs and to improve living standard, but a noticeable fact is that CO2 emission per capita induced by household consumption in developed areas of China had reached a quite high level. Adjustment in lifestyle towards a low-carbon society is in urgent need.
