Abstract: In this paper, emergy analysis method is used to calculate the input and output items of five types of agricultural land in the agricultural system of the Yangtze River Economic Belt from 2010 to 2019, including cultivated land, garden land, forest land, pasture grassland, and aquaculture water surface. An agricultural emergy efficiency evaluation index system was constructed for in-depth research on the emergy structure and efficiency of agricultural input and output in this region. The influencing factors of agricultural production activities and the contribution of each factor were analyzed through the LMDI decomposition model. The results show that from 2010 to 2019, the total input and output emergy of the agricultural system in the Yangtze River Economic Belt increased, and the net emergy yield rate continued to decline. The agricultural input-output efficiencies of the 11 provinces and cities in the Yangtze River Economic Belt are quite different. Except for Shanghai, the total input-output emergy values of other 10 provinces were all increased with various degrees. The net emergy yield rate of agricultural system in most provinces had been declined, and the overall distribution pattern of the net emergy yield rate is high in the east and low in the west. The changes in the comprehensive index of sustainable agricultural utilization in different provinces and cities are different. In general, the overall sustainability of the agricultural system in the Yangtze River Economic Belt has been deteriorating. The factor that has the greatest impact on the sustainable development of agriculture in the 10 years from 2010 to 2019 is the effect of the input structure. Therefore, the primary measure for achieving sustainable development of agriculture in the Yangtze River Economic Belt, is to adjust the agricultural input structure.

Key words: Yangtze River Economic Belt, input-output, emergy, agriculture