吉林省水稻生产的碳足迹与水足迹时空变化特征

Temporal and spatial characteristics of carbon footprint and water footprint in rice production in Jilin Province

农业生产对全球气候变暖、水资源短缺和环境污染具有重要影响。碳足迹和水足迹分别是评估温室气体排放和水资源消耗的指标。采用生命周期评价方法,对吉林省水稻生产的碳足迹和水足迹进行核算,分析碳足迹和水足迹的时空变化特征及其构成。结果表明:2007—2017年吉林省水稻生产的碳足迹年均值为0.74 kg·kg^(-1)。甲烷排放是水稻生产碳足迹的主要组分,占比为41.55%,其次为化肥施用导致的温室气体排放,占比为21.18%。2007—2017年吉林省水稻生产的水足迹呈波动下降趋势,年均值为147 L·kg^(-1),其中:水稀缺足迹为122 L·kg^(-1),约占83%,水劣化足迹为25 L·kg^(-1),约占17%。碳足迹和水足迹的高值区和低值区在空间上分布不一致,吉林省西部和中部地区的水足迹较大、碳足迹较小,而东部、中东部地区碳足迹较大、水足迹较小。相关分析表明,碳足迹和水足迹呈负相关。

Agricultural production has an important impact on global warming,water scarcity and environment pollution.Carbon footprint(CF)and water footprint(WF)are indicators for evaluating greenhouse gas(GHG)emissions and water consumption,respectively.Based on the life cycle assessment method,we calculated the CF and WF in rice production,and analyzed the temporal and spatial characteristics and composition of the CF and WF in Jilin Province.The results showed that the CF fluctuated from 2007 to 2017,with an annual average value of 0.74 kg·kg^(-1).Methane emission from rice fields was the main source of CF in rice production,accounting for 41.55%,followed by GHG emissions caused by fertilizer applications,accounting for 21.18%.From 2007 to 2017,the WF showed a fluctuating downward trend,with an annual average value of 147 L·kg^(-1),of which the water scarcity footprint(WSF)was 122 L·kg^(-1),accounting for about 83%,and the water degradation footprint(WDF)was 25 L·kg^(-1),accounting for about 17%.The spatial differences of rice WF and CF in Jilin Province were obvious.The areas with higher WF were found in the western and central regions of Jilin Province,while the areas with higher CF were found in the eastern and central eastern regions of Jilin Province.Correlation analysis showed that CF and WF were negatively correlated.