[Objective] The aim was to overview the emission of greenhouse gases in farmland. [Method] Based on domestic and foreign references, production mechanism, discharging characters and major influential factors of CO2, C...[Objective] The aim was to overview the emission of greenhouse gases in farmland. [Method] Based on domestic and foreign references, production mechanism, discharging characters and major influential factors of CO2, CH4 and N2O in soils of farmland were overviewed. [Result] Production and discharge of CO2, CH. and N2O played an important role in circulation of carbon and nitrogen in terrestrial ecosystem and constituted a key method for carbon and nitrogen output. It is significant to conduct research on reduction of greenhouse gas and increase of absorption. [Conclusion] The research is beneficial for exploration on discharge rule and influential factors of greenhouse gases, providing theoretical references for reduction of greenhouse gases and study on climate change.展开更多
Environmental issues and rising fuel prices necessitate better energy-etlicwncy in all sectors, The shipping industry is one of the major stakeholders, responsible for 3% of global CO2 emissions, 14%-15% of global NOx...Environmental issues and rising fuel prices necessitate better energy-etlicwncy in all sectors, The shipping industry is one of the major stakeholders, responsible for 3% of global CO2 emissions, 14%-15% of global NOx emissions, and 16% of global SOx emissions. In addition, continuously rising fuel prices are also an incentive to focus on new ways for better energy-effectiveness. The green ship concept requires exploring and implementing technology on ships to increase energy-efficiency and reduce emissions. Ship operation is an important topic with large potential to increase cost-and-energy-effectiveness. This paper provided a comprehensive review of basic concepts, principles, and potential of operational options for green ships. The key challenges pertaining to ship crew i.e. academic qualifications prior to induction, in-service training and motivation were discussed. The author also deliberated on remedies to these challenges.展开更多
Waste disposal is a major source of greenhouse gas emissions such as methane, carbon dioxide and nitrous oxide. In China, rapid economic growth and urbanization have led to increasing solid waste generation and greenh...Waste disposal is a major source of greenhouse gas emissions such as methane, carbon dioxide and nitrous oxide. In China, rapid economic growth and urbanization have led to increasing solid waste generation and greenhouse gas emissions from the waste sector. Based on the first-order decay （FOD） method recommended by the 2006 IPCC Guidelines, this paper systematically estimates China＇s carbon emissions from the waste sector and forecasts their peak. Results indicate that between 1981 and 2009, China＇s carbon emissions from the waste sector surged, possibly peaking by around 2024. In comparison with developed countries, there is a large potential to improve waste disposal in China. Industrial upgradation and waste disposal improvement will help reduce waste generation and carbon emissions from the waste sector.展开更多
Soil samples were taken from an Ermans birch （Betula ermanii）-dark coniferous forest （Picea jezoensis and Abies nephrolepis） ecotone growing on volcanic ejecta in the northern slope of Changbai Mountains of Northe...Soil samples were taken from an Ermans birch （Betula ermanii）-dark coniferous forest （Picea jezoensis and Abies nephrolepis） ecotone growing on volcanic ejecta in the northern slope of Changbai Mountains of Northeast China, to compare soil carbon （C） and nitrogen （N） transformations in the two forests. The soil type is Umbri-Gelic Cambosols in Chinese Soil Taxonomy. Soil samples were incubated aerobically at 20℃ and field capacity of 700 g kg^-1 over a period of 27 weeks. The amount of soil microbial biomass and net N mineralization were higher in the Ermans birch than the dark coniferous forest （P 〈 0.05）, whereas the cumulative C mineralization （as CO2 emission） in the dark coniferous forest exceeded that in the Ermans birch （P 〈 0.05）. Release of the cumulative dissolved organic C and dissolved organic N were greater in the Ermans birch than the dark coniferous forest （P 〈 0.05）. The results suggested that differences of forest types could result in considerable change in soil C and N transformations.展开更多
To study effect of C2H2 and change of headspace gas on N2O emission, denitrification, as well as CO2emission, slumes of an agricultural soil were anaerobically incubated for 7 da3’s at 25 ℃. Both N2O reduction and C...To study effect of C2H2 and change of headspace gas on N2O emission, denitrification, as well as CO2emission, slumes of an agricultural soil were anaerobically incubated for 7 da3’s at 25 ℃. Both N2O reduction and CO2 emissions were inhibited by the addition of 100 mL L-1 of C2H2. However, the inhibition to CO2 emission was alleviated by the replacement of headspace gas, and the N2O emission was enhanced by the replacement. Acetylene disappeared evidently from the soil slumes during the incubation. Consequently results obtained from the traditional C2H2 blocking technique for determination of denitrification rate, especially in a long-time incubation, should be explained with care because of its side effect existing in the incubation environments without change of headspace gas. To reduce the possible side effect on the processes other than denitrification, it is suggested that headspace gas should be replaced several times during a long-time incubation.展开更多
The main objective of this study was to establish optimal incineration conditions through the analysis of pollutant formation mechanisms involved in the combustion process of a retort incinerator. Calorific values of ...The main objective of this study was to establish optimal incineration conditions through the analysis of pollutant formation mechanisms involved in the combustion process of a retort incinerator. Calorific values of several types of municipal solid wastes were determined and related to specific incinerability indexes. The incinerability testing concerning this study was conducted on residues with an incinerability index （II） of 123. The samples were tested under different conditions： with and without chamber preheating, varying the percentage of inlet air （25, 50 and 75% of the system capacity）, measuring the temperatures of the primary and secondary chambers, and gauging the CO and NO stack emissions with an electrochemical cell. With comparative purposes in mind, samples with indexes ofI = 112, I = 123, I = 130 and I = 132 were also tested to assess the influence of the II on pollutant emissions.展开更多
基金Supported by the Special R&D Fund for Public Welfare IndustryApplication of Remote Sensing Technology in Agrometeorological Forecast(GYHY201106027)~~
文摘[Objective] The aim was to overview the emission of greenhouse gases in farmland. [Method] Based on domestic and foreign references, production mechanism, discharging characters and major influential factors of CO2, CH4 and N2O in soils of farmland were overviewed. [Result] Production and discharge of CO2, CH. and N2O played an important role in circulation of carbon and nitrogen in terrestrial ecosystem and constituted a key method for carbon and nitrogen output. It is significant to conduct research on reduction of greenhouse gas and increase of absorption. [Conclusion] The research is beneficial for exploration on discharge rule and influential factors of greenhouse gases, providing theoretical references for reduction of greenhouse gases and study on climate change.
基金Foundation item： Supported by the National Natural Science Foundation of China under Grant No.51079032, and the Excellent Youth Foundation of Heilongjiang Province of China.
文摘Environmental issues and rising fuel prices necessitate better energy-etlicwncy in all sectors, The shipping industry is one of the major stakeholders, responsible for 3% of global CO2 emissions, 14%-15% of global NOx emissions, and 16% of global SOx emissions. In addition, continuously rising fuel prices are also an incentive to focus on new ways for better energy-effectiveness. The green ship concept requires exploring and implementing technology on ships to increase energy-efficiency and reduce emissions. Ship operation is an important topic with large potential to increase cost-and-energy-effectiveness. This paper provided a comprehensive review of basic concepts, principles, and potential of operational options for green ships. The key challenges pertaining to ship crew i.e. academic qualifications prior to induction, in-service training and motivation were discussed. The author also deliberated on remedies to these challenges.
文摘Waste disposal is a major source of greenhouse gas emissions such as methane, carbon dioxide and nitrous oxide. In China, rapid economic growth and urbanization have led to increasing solid waste generation and greenhouse gas emissions from the waste sector. Based on the first-order decay （FOD） method recommended by the 2006 IPCC Guidelines, this paper systematically estimates China＇s carbon emissions from the waste sector and forecasts their peak. Results indicate that between 1981 and 2009, China＇s carbon emissions from the waste sector surged, possibly peaking by around 2024. In comparison with developed countries, there is a large potential to improve waste disposal in China. Industrial upgradation and waste disposal improvement will help reduce waste generation and carbon emissions from the waste sector.
基金Project supported by the National Natural Science Foundation of China(No.90411020)the National Key Basic Research Program(973 Program)of China(No.2002CB412502)
文摘Soil samples were taken from an Ermans birch （Betula ermanii）-dark coniferous forest （Picea jezoensis and Abies nephrolepis） ecotone growing on volcanic ejecta in the northern slope of Changbai Mountains of Northeast China, to compare soil carbon （C） and nitrogen （N） transformations in the two forests. The soil type is Umbri-Gelic Cambosols in Chinese Soil Taxonomy. Soil samples were incubated aerobically at 20℃ and field capacity of 700 g kg^-1 over a period of 27 weeks. The amount of soil microbial biomass and net N mineralization were higher in the Ermans birch than the dark coniferous forest （P 〈 0.05）, whereas the cumulative C mineralization （as CO2 emission） in the dark coniferous forest exceeded that in the Ermans birch （P 〈 0.05）. Release of the cumulative dissolved organic C and dissolved organic N were greater in the Ermans birch than the dark coniferous forest （P 〈 0.05）. The results suggested that differences of forest types could result in considerable change in soil C and N transformations.
文摘To study effect of C2H2 and change of headspace gas on N2O emission, denitrification, as well as CO2emission, slumes of an agricultural soil were anaerobically incubated for 7 da3’s at 25 ℃. Both N2O reduction and CO2 emissions were inhibited by the addition of 100 mL L-1 of C2H2. However, the inhibition to CO2 emission was alleviated by the replacement of headspace gas, and the N2O emission was enhanced by the replacement. Acetylene disappeared evidently from the soil slumes during the incubation. Consequently results obtained from the traditional C2H2 blocking technique for determination of denitrification rate, especially in a long-time incubation, should be explained with care because of its side effect existing in the incubation environments without change of headspace gas. To reduce the possible side effect on the processes other than denitrification, it is suggested that headspace gas should be replaced several times during a long-time incubation.
文摘The main objective of this study was to establish optimal incineration conditions through the analysis of pollutant formation mechanisms involved in the combustion process of a retort incinerator. Calorific values of several types of municipal solid wastes were determined and related to specific incinerability indexes. The incinerability testing concerning this study was conducted on residues with an incinerability index （II） of 123. The samples were tested under different conditions： with and without chamber preheating, varying the percentage of inlet air （25, 50 and 75% of the system capacity）, measuring the temperatures of the primary and secondary chambers, and gauging the CO and NO stack emissions with an electrochemical cell. With comparative purposes in mind, samples with indexes ofI = 112, I = 123, I = 130 and I = 132 were also tested to assess the influence of the II on pollutant emissions.
