Based On LCA Analysis Of Spatiotemporal Differentiation And Influencing Factors Of Water Footprint And Carbon Footprint Of Rice Production In Jilin Province

Agricultural production has a major impact on global warming,water shortage and pollution.Agriculture is the largest water consumption sector in the world,accounting for 61%of the total water consumption in China.And the greenhouse gas emissions caused by agricultural activities accounted for 7.9%of national greenhouse gas emissions.Rice,as a major food crop,its production process would cause a series of negative effects on the environment.It is estimated that greenhouse gas emissions from rice farming in China account for 22.6%of agricultural activity emissions,and rice fields are also an important source of atmospheric methane emissions,accounting for 40.1%of the entire agricultural activities.At the same time,the process of rice cultivation also needs sufficient water,which puts great pressure on water resources.Therefore,how to scientifically and effectively evaluate the environmental impact of rice production is particularly important.Water footprint and carbon footprint are indicators to assess water consumption and greenhouse gas emissions respectively,which providing a new way to comprehensively assessing the impact of agricultural production on the environment.On the basis of summarizing the current status of domestic and foreign water footprint and carbon footprint research,this paper used the life cycle assessment method to calculate the water footprint and carbon footprint of rice production in Jilin Province from 2004 to 2018,and analyzed the spatio-temporal variation characteristics and composition of water footprint and carbon footprint.In addition,STIRAPT model and principal component analysis were used to explore the influencing factors water footprint and carbon footprint in rice production during the research period,which provided a theoretical basis for the sustainable development of agriculture.The main conclusions are as follows:（1）The water footprint of rice production in Jilin Province showed a fluctuating downward trend from 2004 to 2018,with an annual average of 149.95 L H₂Oeq kg^-1,of which the water scarcity footprint was 124.02 L H₂Oeq kg^-1,accounting for about83%,and the water degradation footprint was 25.93 L H₂Oeq kg^-1,accounting for about 17%.And the water footprint and water scarcity footprint showed the consistent trend.（2）The carbon footprint of rice production in Jilin Province fluctuated and increased from 2004 to 2018,with an annual mean value of 0.595 kg CO₂eq kg^-1.In the composition of carbon footprint,44.33%of greenhouse gas emissions came from methane,which was the main greenhouse gas emission from rice production,followed by the greenhouse gas emission from fertilizer application,accounting for26.58%.（3）Correlation analysis showed that carbon footprint and water footprint were negatively correlated.Moreover,the high-value and low-value areas of carbon footprint and water footprint were not consistent in spatial distribution,showing obvious regional differences.The western and central regions of Jilin Province had a larger water footprint and a smaller carbon footprint,while the eastern and central regions had a higher carbon footprint and a smaller water footprint.（4）The STIRAPT model and principal component analysis were used to analyze the influencing factors of water footprint and carbon footprint during rice production in Jilin Province.The results showed that the annual precipitation and rice yield per unit area were the most important influencing factor for the change of water footprint.However,the total power of agricultural machinery,the application amount of chemical fertilizer and the effective irrigation area had a greater impact on the change of carbon footprint.（5）For rice production in Jilin Province,on the basis of ensuring the high yield of rice,different mitigation measures should be formulated in accordance with the characteristics of the natural environment in different regions.We can optimize the water footprint and carbon footprint of rice production and promote the sustainable development of agriculture by improving the fertilization method,improving the use efficiency of agricultural machinery and formulating reasonable irrigation schemes.