全球变暖已经成为不争的事实,陆地生态系统碳循环的研究受到了各界广泛关注,是当前全球变化研究中的重点。土壤CO_(2)排放是陆地生态系统与大气间二氧化碳交换的最大通量之一,当前陆地生态系统中土壤CO_(2)排放如何响应全球气候变暖及...全球变暖已经成为不争的事实,陆地生态系统碳循环的研究受到了各界广泛关注,是当前全球变化研究中的重点。土壤CO_(2)排放是陆地生态系统与大气间二氧化碳交换的最大通量之一,当前陆地生态系统中土壤CO_(2)排放如何响应全球气候变暖及其影响因素仍不清楚,限制了对土壤碳循环过程及影响机制的深入认识。旨在明确全球变暖背景下陆地生态系统中土壤CO_(2)排放格局及影响因素。基于Web of Science、PubMed和中国知网等中英文期刊数据库,充分收集全球范围内的相关野外试验文献81篇,提取出65个研究位置和213组相关研究数据,采用Meta分析方法探讨陆地生态系统土壤CO_(2)排放对增温的响应特征,分析其与海拔、气候、土壤含水量、容重(BD)、pH、全氮(TN)和土壤有机碳(SOC)的相关关系。结果表明:陆地生态系统中土壤CO_(2)排放对增温整体有显著的正向响应,在农、林、草生态系统中,增温使土壤CO_(2)排放分别显著增加13.1%、18.0%、5.9%(P<0.05),森林生态系统对增温响应的正效应最强烈;增温能在短时期内促进土壤呼吸,但随着增温持续时间增加,土壤呼吸对温度的敏感性会降低,对温度变化产生适应性,从而使其对增温的响应能力减弱;响应特征受到环境因子、土壤特性以及其他试验条件等的影响,绝大多数条件下对增温表现出显著的正响应特征,不同影响因子之间共同作用、相互影响。增温通常能够改变植物生物量、土壤养分含量及微生物数量和活性,从而影响到植被根际呼吸和土壤呼吸速率。相关分析表明,海拔对土壤CO_(2)排放有显著负向影响,而年均气温、年均降水量、土壤含水量和仪器嵌入土壤深度则对土壤CO_(2)排放产生显著正向影响。这些结果对于理解全球土壤CO_(2)排放的时空变化格局有重要意义,也为准确评价全球变暖背景下土壤碳汇功能及其持续性提供理论依据。展开更多
China’s first carbon dioxide(CO_(2))measurement satellite mission,TanSat,was launched in December 2016.This paper introduces the first attempt to detect anthropogenic CO_(2) emission signatures using CO_(2) observati...China’s first carbon dioxide(CO_(2))measurement satellite mission,TanSat,was launched in December 2016.This paper introduces the first attempt to detect anthropogenic CO_(2) emission signatures using CO_(2) observations from TanSat and NO_(2) measurements from the TROPOspheric Monitoring Instrument(TROPOMI)onboard the Copernicus Sentinel-5 Precursor(S5P)satellite.We focus our analysis on two selected cases in Tangshan,China and Tokyo,Japan.We found that the TanSat XCO_(2) measurements have the capability to capture the anthropogenic variations in the plume and have spatial patterns similar to that of the TROPOMI NO_(2) observations.The linear fit between TanSat XCO_(2) and TROPOMI NO_(2) indicates the CO_(2)-to-NO_(2) ratio of 0.8×10^(-16) ppm(molec cm^(-2))^(-1) in Tangshan and 2.3×10^(-16) ppm(molec cm^(-2))^(-1) in Tokyo.Our results align with the CO_(2)-to-NOx emission ratios obtained from the EDGAR v6 emission inventory.展开更多
The argument over fiscal decentralization and carbon dioxide emission(CO_(2))reduction has received much attention.However,evidence to back this claim is limited.Economic theory predicts that fiscal decentralization a...The argument over fiscal decentralization and carbon dioxide emission(CO_(2))reduction has received much attention.However,evidence to back this claim is limited.Economic theory predicts that fiscal decentralization affects environmental quality,but the specifics of this relationship are still up for debate.Some scholars noted that fiscal decentralization might lead to a race to the top,whereas others contended that it would result in a race to the bottom.In light of the current debates in environmental and development economics,this study aims to provide insight into how this relationship may function in South Africa from 1960 to 2020.In contrast to the existing research,the present study uses a novel dynamic autoregressive distributed lag simulation approach to assess the positive and negative changes in fiscal decentralization,scale effect,technique effect,technological innovation,foreign direct investment,energy consumption,industrial growth,and trade openness on CO_(2)emissions.The following are the main findings:(i)Fiscal decentralization had a CO_(2)emission reduction impact in the short and long run,highlighting the presence of the race to the top approach.(ii)Economic growth(as represented by the scale effect)eroded ecological integrity.However,its square(as expressed by technique effect)aided in strengthening ecological protection,validating the environmental Kuznets curve hypothesis.(iii)CO_(2)emissions were driven by energy utilization,trade openness,industrial value-added,and foreign direct investment,whereas technological innovation boosted ecological integrity.Findings suggest that further fiscal decentralization should be undertaken through further devolution of power to local entities,particularly regarding environmental policy issues,to maintain South Africa’s ecological sustainability.South Africa should also establish policies to improve environmental sustainability by strengthening a lower layer of government and clarifying responsibilities at the national and local levels to fulfill the energy-saving functions of fiscal expenditures.展开更多
文摘全球变暖已经成为不争的事实,陆地生态系统碳循环的研究受到了各界广泛关注,是当前全球变化研究中的重点。土壤CO_(2)排放是陆地生态系统与大气间二氧化碳交换的最大通量之一,当前陆地生态系统中土壤CO_(2)排放如何响应全球气候变暖及其影响因素仍不清楚,限制了对土壤碳循环过程及影响机制的深入认识。旨在明确全球变暖背景下陆地生态系统中土壤CO_(2)排放格局及影响因素。基于Web of Science、PubMed和中国知网等中英文期刊数据库,充分收集全球范围内的相关野外试验文献81篇,提取出65个研究位置和213组相关研究数据,采用Meta分析方法探讨陆地生态系统土壤CO_(2)排放对增温的响应特征,分析其与海拔、气候、土壤含水量、容重(BD)、pH、全氮(TN)和土壤有机碳(SOC)的相关关系。结果表明:陆地生态系统中土壤CO_(2)排放对增温整体有显著的正向响应,在农、林、草生态系统中,增温使土壤CO_(2)排放分别显著增加13.1%、18.0%、5.9%(P<0.05),森林生态系统对增温响应的正效应最强烈;增温能在短时期内促进土壤呼吸,但随着增温持续时间增加,土壤呼吸对温度的敏感性会降低,对温度变化产生适应性,从而使其对增温的响应能力减弱;响应特征受到环境因子、土壤特性以及其他试验条件等的影响,绝大多数条件下对增温表现出显著的正响应特征,不同影响因子之间共同作用、相互影响。增温通常能够改变植物生物量、土壤养分含量及微生物数量和活性,从而影响到植被根际呼吸和土壤呼吸速率。相关分析表明,海拔对土壤CO_(2)排放有显著负向影响,而年均气温、年均降水量、土壤含水量和仪器嵌入土壤深度则对土壤CO_(2)排放产生显著正向影响。这些结果对于理解全球土壤CO_(2)排放的时空变化格局有重要意义,也为准确评价全球变暖背景下土壤碳汇功能及其持续性提供理论依据。
基金supported by the National Key Research And Development Plan (2019YFE0127500)International Partnership Program of the Chinese Academy of Sciences (060GJHZ2022070MI)+2 种基金the Key Research Program of the Chinese Academy of Sciences (ZDRWZS-2019-1)the Finland-China mobility cooperation project funded by the Academy of Finland (No. 348596)Financial support for the Academy of Finland (No. 336798)
文摘China’s first carbon dioxide(CO_(2))measurement satellite mission,TanSat,was launched in December 2016.This paper introduces the first attempt to detect anthropogenic CO_(2) emission signatures using CO_(2) observations from TanSat and NO_(2) measurements from the TROPOspheric Monitoring Instrument(TROPOMI)onboard the Copernicus Sentinel-5 Precursor(S5P)satellite.We focus our analysis on two selected cases in Tangshan,China and Tokyo,Japan.We found that the TanSat XCO_(2) measurements have the capability to capture the anthropogenic variations in the plume and have spatial patterns similar to that of the TROPOMI NO_(2) observations.The linear fit between TanSat XCO_(2) and TROPOMI NO_(2) indicates the CO_(2)-to-NO_(2) ratio of 0.8×10^(-16) ppm(molec cm^(-2))^(-1) in Tangshan and 2.3×10^(-16) ppm(molec cm^(-2))^(-1) in Tokyo.Our results align with the CO_(2)-to-NOx emission ratios obtained from the EDGAR v6 emission inventory.
文摘The argument over fiscal decentralization and carbon dioxide emission(CO_(2))reduction has received much attention.However,evidence to back this claim is limited.Economic theory predicts that fiscal decentralization affects environmental quality,but the specifics of this relationship are still up for debate.Some scholars noted that fiscal decentralization might lead to a race to the top,whereas others contended that it would result in a race to the bottom.In light of the current debates in environmental and development economics,this study aims to provide insight into how this relationship may function in South Africa from 1960 to 2020.In contrast to the existing research,the present study uses a novel dynamic autoregressive distributed lag simulation approach to assess the positive and negative changes in fiscal decentralization,scale effect,technique effect,technological innovation,foreign direct investment,energy consumption,industrial growth,and trade openness on CO_(2)emissions.The following are the main findings:(i)Fiscal decentralization had a CO_(2)emission reduction impact in the short and long run,highlighting the presence of the race to the top approach.(ii)Economic growth(as represented by the scale effect)eroded ecological integrity.However,its square(as expressed by technique effect)aided in strengthening ecological protection,validating the environmental Kuznets curve hypothesis.(iii)CO_(2)emissions were driven by energy utilization,trade openness,industrial value-added,and foreign direct investment,whereas technological innovation boosted ecological integrity.Findings suggest that further fiscal decentralization should be undertaken through further devolution of power to local entities,particularly regarding environmental policy issues,to maintain South Africa’s ecological sustainability.South Africa should also establish policies to improve environmental sustainability by strengthening a lower layer of government and clarifying responsibilities at the national and local levels to fulfill the energy-saving functions of fiscal expenditures.