湖北省作物系统氮素利用及其环境影响综合评估OA北大核心CHSSCDCSTPCD

Food security,high use-efficiency of resources,and friendly environment are the central concerns of sustainable agricultural development in China.Hubei Province,as a significant agricultural region in the middle and lower reaches of the Yangtze River,requires a comprehensive assessment of nitrogen(N)utilization and its environmental im-pacts in the multi-crop system.We focused on the major cereal crops including rice,wheat,maize,and soybeans as well as cash crops including tea,fruits,and vegetables,and proposed a comprehensive assessment framework to evaluate the N utilization efficiency and its environmental impacts in multi-crop system of Hubei Province in the year of 2020.The results show that there were high N application rates,N surplus,and greenhouse gas(GHG)emissions,but low N use efficiency and partial fertilizer productivity in Hubei Province.The N application rate in Hubei Province was higher than the national average by 43%.The N use efficiency for grain crops was 35.17%,while that for cash crops was only 9.99%.For envi-ronmental impacts,the total N surplus in cash crops(43.36%)was lower than that in grain crops(56.64%),the high-est nitrogen surplus was from rice(38.27%).However,grain crops contributed higher GHG emissions than cash crops.N application rates in Hubei Province demonstrated a pattern with higher values in central area but lower values in the east and west regions.GHG emissions from cash crops were predominantly concentrated in the southern and northern regions of Hubei,while those from grain crops were concentrated in the western and eastern areas.Ammonia emissions per unit area from cash crops were significantly higher than from grain crops,exhibiting a distribution pattern with higher values in the north and south but lower values in the east and west.This research provides a valuable evaluation framework to enhance N use efficiency and reduce N fertilizer inputs and GHG emissions in the multi-crop system.It is recommended that imple-menting coordinated management measures and related policies,adjusting planting structures,and optimizing nitrogen ap-plication based on the specific characteristics of different regions could contribute to improve N utilization efficiency in Hu-bei Province.