Abstract: In order to investigate the effects of organic fertilizer combined with inorganic fertilizer on the distribution and community of soil macrofauna in the sweet potato field under the condition of equal nitrogen, four kinds of organic fertilizer combined with chemical fertilizer were set up during the growth of the sweet potato, including pig manure organic fertilizer, sheep manure organic fertilizer, mushroom residue organic fertilizer and perishable garbage organic fertilizer, and the pure chemical fertilizer and no fertilization were used as the control. The amount of pure nitrogen in each treatment was 150.00 kg/hm². The changes of soil moisture content and pH under different fertilization treatments were investigated, and the distribution and diversity of soil macrofauna in soil were investigated and analyzed. 10 groups of soil macrofauna were captured, including Hymenoptera, Collembola, Araneae, Diptera, Coleoptera, Hemiptera, Orthoptera, Lepidoptera, Staphylinidae and Oligotricha. Hymenoptera was the dominant group among soil macrofauna treated with different fertilizers. There were the most macrofaunas in the surface soil of the 0~5 cm sample plot. The analysis of soil macrofauna diversity showed that the Shannon-Wiener diversity index of pig manure organic fertilizer combined with chemical fertilizer treatment was 2.138, which was the highest among all treatments, increasing by 60.51% compared to the no fertilizer control and 12.23% compared to the pure chemical fertilizer control. The number of groups and individuals in this treatment was also the highest. The diversity index of the four types of organic fertilizer was higher than that of the no fertilizer control, and the application of organic fertilizer could improve biodiversity, which was conducive to the sustainable development of agricultural ecology.

Key words: equal nitrogen, organic fertilizer, inorganic fertilizer, combined applying, sweet potato field, soil macrofauna, distribution, community