| Carbon emission reduction governance and carbon emission efficiency improvement based on the dual carbon theory are important for promoting the high-quality development of the Yangtze River Economic Belt,and exploring the spatial and temporal evolution characteristics and driving mechanisms of carbon emission efficiency can provide important support for achieving the dual carbon goal of the Yangtze River Economic Belt.Based on the panel data of 105 prefecture-level cities in the Yangtze River Economic Belt from 2000 to 2019,the directional distance function(DDF)and the truncated random Tobit regression model were used to analyze the carbon emission efficiency and its influencing factors in the Yangtze River Economic Belt.The Seoul index systematically studied the temporal and spatial evolution pattern,regional differences and formation mechanism of carbon emission efficiency in the Yangtze River Economic Belt and its different belt segments from 2000 to 2019.The results show:(1)From the perspective of sources,the carbon emissions of agricultural land use in the Yangtze River Economic Belt are greater than the carbon emissions of energy consumption.From the perspective of agricultural land use,the carbon emissions in 2002 were 2.03×1011 tons,accounting for 86.38%of the total emissions,and in 2018,the emissions were 3.34×1011 tons,accounting for 85.66%of the total emissions;From the perspective of energy consumption,the carbon emission in 2001 was 3.08×1010 tons,accounting for 12.19%of the total emissions;in 2009,the emissions were 7.88×1010 tons,accounting for 23.16%of the total emissions;in 2002,the total emissions were the smallest,at 2.35×1011 tons.The total emissions in 2018 were the largest,reaching 3.74×1011 tons.(2)Based on DDF model with Meta and group frontiers,the average value of agricultural carbon emission efficiency in the Yangtze River Economic Zone and each segment during the study period is generally inefficient,with most of the average efficiency values under the common frontier below 0.8 and most of the average efficiency values under the grouped frontier below 0.9.Both have not reached the effective value for a long time and there are some regional differences,but they all show a fluctuating upward trend.The upper section shows inefficiency in the first period and improves and remains relatively stable in the later period under different frontier conditions.The middle section is inefficient for a long time under both frontier conditions.The gap between actual efficiency value and potential efficiency value is small.(3)From the perspective of time trends,the agricultural carbon emission efficiency of the Yangtze River Economic Belt from 2000 to 2019,the efficiency of the entire Yangtze River Economic Belt was the lowest in 2006,and the highest in 2019.The fluctuation trend of the upper,middle and lower belts is the same,and the efficiency has a strong convergence.From the perspective of agricultural carbon emission efficiency in different belt sections,cities in the middle and lower sections of the Yangtze River,as well as Chongqing and Guizhou have higher efficiency;cities with high grain yield in the middle section have lower efficiency,and the average efficiency of the lower section is higher than that of the middle and lower sections.near.From the perspective of city scale,Shanghai has the highest average efficiency of agricultural carbon emission in the period of 2000-2019,with an average value of 0.94 in 2000-2019.Except Liupanshui City in Guizhou,the top 15 cities are mainly distributed in Jiangsu Province and Zhejiang Province;The ecological efficiency of agricultural carbon emission in Shiyan City,Hubei Province is the lowest,with an average value of 0.15 from 2000 to 2019.The last 15 cities are mainly distributed in Hubei,Hunan,Jiangxi and Sichuan in the middle section,with an average score of less than 0.33.The overall regional differences in agricultural carbon emission efficiency in the Yangtze River Economic Belt are large,with significant regional differences in the middle and upper sections,and small regional differences in the lower section.(4)The influencing factors of agricultural carbon emission efficiency in the Yangtze River Economic Belt have significant spatial scale effects.From the analysis of the influence properties of the same influencing factors at different scales,farmers’ per capita consumption expenditure,planting industry structure,urbanization rate and R&D investment have a positive impact on the regional agricultural carbon emission efficiency.From the analysis of the influence properties of the same influencing factors at different scales,farmers’ per capita consumption expenditure,planting industry structure,urbanization rate and R&D investment have a positive impact on the regional agricultural carbon emission efficiency.It shows that the improvement of urbanization level in the Yangtze River economic belt plays a significant role in the realization of agricultural carbon reduction goalWith different perspectives of common frontier and grouped frontier,the DDF non-expectation model is used to analyze the efficiency and regional differences of agricultural carbon emissions in the Yangtze River Economic Belt and the upper,middle and lower sections,and the heterogeneity of decision units is considered by Tobit regression model at different scales.The research results can not only provide guidance for the implementation of low-carbon agricultural practices in the Yangtze River Economic Zone,but also enrich the theoretical approach of regional agricultural carbon emission efficiency evaluation and provide methodological reference for agricultural carbon emission efficiency evaluation. |
