2001—2020年福建省县域单元农业碳排放核算和时空演变特征分析

Accounting and Analyzing Spatial-temporal Evolution Characteristics of Agricultural Carbon Emissions at County Units of Fujian Province During 2001—2020

[目的]分析福建省县域尺度农业净碳排放量时空特征,为福建省及其他各省市区制定碳减排对策提供参考依据。[方法]基于种植业和畜牧业的12种碳源构建农业碳排放核算清单,采用碳排放因子法测算出农业碳排放总量;结合福建省农业特征选取7种主要农作物计算碳吸收量;并利用探索性空间分析方法分析了2001—2020年福建省农业净碳排放的时空演变特征。[结果](1)研究期内净碳排放量呈现出先上升后下降的倒“V”型变化趋势。碳源方面,农地利用碳排放占据较大比例;碳汇方面,水稻、蔬菜和甘蔗对碳吸收的贡献较大。大部分县(市)农业碳排放强度呈下降趋势,但年均下降幅度较小。(2)福建省县域碳排放量存在显著的全局空间正相关,呈现出空间集聚特征,聚集态势以高高集聚和低低集聚为主。农业碳排放强度空间分布格局变化较大,整体呈现下降趋势,其中约有一半的县(市)处于较低强度区。(3)2001—2020年福建省各县(市)的空间等级分布格局有一定程度的变动,中等排放区和中低排放区数量增多,高等排放区、中高排放区和低排放区数量减少,两极分化情况有所缓解。[结论]2001—2020年福建省大部分县域农业碳排放量和碳排放强度都呈下降趋势,碳减排取得了一定成效,但下降幅度不够大,未来还应从政策激励、产业结构优化等方面采取措施强化减排效果,促进农业低碳转型。

[Objective]The temporal and spatial characteristics of net carbon emissions from agriculture at county scale in Fujian Province were analyzed in order to provide references for the formulation of carbon emission reduction countermeasures in Fujian Province and in other provinces and municipalities.[Methods]We constructed an accounting inventory of agricultural carbon emissions based on 12 carbon sources in plantation and livestock industries,and measured the total agricultural carbon emissions by using the carbon emission factor method.We selected seven major crops to calculate carbon uptake by combining with the agricultural characteristics of Fujian Province.We analyzed the spatial and temporal characteristics of the net agricultural carbon emissions in Fujian Province from 2001 to 2020 by using the exploratory spatial analysis method.[Results](1)During the study period,the net carbon emissions showed an inverted“V”trend of first increasing and then decreasing.In terms of carbon sources,carbon emissions from agricultural land use accounted for a larger proportion.In terms of carbon sinks,rice,vegetables,and sugarcane contributed more to carbon sequestration.The intensity of agricultural carbon emissions at most counties(cities)showed a decreasing trend,but the average annual decline was small.(2)There was a significant global spatial positive correlation of carbon emissions at counties in Fujian Province,showing spatial agglomeration characteristics.The agglomeration pattern was dominated by high-high and low-low agglomeration.The spatial distribution pattern of the intensity of agricultural carbon emissions changed considerably,with an overall decreasing trend,in which about half of the counties(cities)were in the lower intensity zone.(3)The spatial class distribution pattern of counties(cities)in Fujian Province from 2001 to 2020 had changed to a certain extent,with an increase in the number of medium-emission zones and medium-low-emission zones,and a decrease in the number of high-emission zones,medium-high-emission zones,and low-emission zones,and the polarization was alleviated.[Conclusion]During 2001—2020,most counties in Fujian Province have showed a decreasing trend in agricultural carbon emissions and carbon emission intensity,and carbon emission reduction has achieved certain results,but the decline has not been large enough.In the future,policy incentives and measures should be taken to optimize industrial structure,therefore to strengthen emission reductions and to promote the transition to low-carbon agriculture.