摘要
在测算和分析2002~2021年中国省域农业净碳汇的时空格局变化基础上,利用随机森林模型识别关键影响因素及其非线性响应关系.结果表明:中国农业呈持续增长的碳盈余状态,净碳汇总量由2002年的22965.13万t增至2021年的49992.53万t,增幅达117.69%.多数省份实现碳中和并逐渐偏向高碳盈状态,净碳汇总量呈由东向西依次递减的分布格局,并存在高值集聚增多、低值集聚减少的向好趋势,20a间黑龙江、内蒙古、河南和山东净碳汇增加量超过2000万t,仅浙江、福建、海南、上海和北京净碳汇量下降.净碳汇强度的空间集聚和非均衡趋势明显,东北、中部和西南地区净碳汇强度较高,大部分省份的净碳汇强度处于0~1.5t C/万元间,仅黑龙江和吉林始终高于1.5t C/万元,而西藏和青海则为负值.灌溉条件、机械化秸秆还田、机械化免耕播种、粮食单产等因素的影响均具有非线性,受教育程度与净碳汇间呈“倒U型”,机械化水平具有显著抑制作用,其他因素呈波动的正向影响.
Given the current climate goals of carbon peaking and carbon neutrality,it is crucial to investigate the spatiotemporal patterns and drivers of agricultural net carbon sink in China.This study aims at promoting high-quality agricultural development and achieving the“dual carbon”goal.Based on the total amount and intensity of China’s provincial net carbon sink from 2002 to 2021,a random forest model was used to identify the primary drivers of the agricultural net carbon sink and its nonlinear response relationship.The results show that:(1)China’s agricultural sector is experiencing a slow but consistent carbon surplus growth,demonstrating an attained carbon neutrality and transitioning towards an elevated carbon surplus state in most provinces;(2)the total net carbon sink tends to decline from the east to the west,with an increase in high-value agglomeration and a decrease in low-value agglomeration;(3)the spatial agglomeration and non-equilibrium of net carbon sink intensity tend to be obvious,with a higher intensity in the northeast,central,and southwest;and(4)the key factors driving agricultural net carbon sink include irrigation conditions,mechanized straw return,mechanized no-tillage sowing,grain yield,etc.,exhibiting nonlinear effects on the net carbon sink.Specifically,there is a U-shaped relationship between education level and agricultural net carbon sink,and mechanization level has a significant inhibitory effect,while other factors demonstrate a positive fluctuation effect.
作者
贯君
张少鹏
任月
盛春光
GUAN Jun;ZHANG Shao-peng;REN Yue;SHENG Chun-guang(School of Economics and Management,Northeast Forestry University,Harbin 150040,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2024年第2期1158-1170,共13页
China Environmental Science
基金
国家自然科学基金青年基金资助项目(72201054)
教育部人文社会科学研究青年基金资助项目(23YJC790036)
中央高校基本科研业务费专项资金资助项目(2572021BM02)。
关键词
农业净碳汇
时空分异
影响因素
随机森林模型
中国
agricultural net carbon sequestration
spatial-temporal variation
influencing factors
random forest model
China
