Abstract:
Objective Based on a long-term located field experiment of ecological rice-eel co-culture, the effects of different fertilization on the physicochemical properties and biological community of paddy soil at different depths (0 ~ 20 cm and 20 ~ 40 cm) were investigated under ecological planting and cultivation mode of rice and eel.
Method Six treatments were set up in the field plot experiment: regular fertilization in conventional paddy field (RT), check control without fertilization in ecological rice-eel co-culture (CK), regular fertilization in ecological rice-eel co-culture (IRT), 70% fertilization in ecological rice-eel co-culture (IT70%), 70% fertilization with straw returning in ecological rice-eel co-culture (ITS70%), 70% fertilization with organic fertilizer in ecological rice-eel co-culture (ITO70%).
Result Compared with RT, ITS70% significantly reduced bulk density in 0 ~ 20 cm and 20 ~ 40 cm soil, and significantly increased R0.25, MWD, GWD in 0 ~ 20 cm and 20 ~ 40 cm soil by 32.15%, 75.47%, 103.20% and 41.04%, 100%, 118%, respectively. The contents of organic matter in 0 ~ 20 cm and 20 ~ 40 cm soil were significantly increased by 31.03% and 39.23%, respectively. The copy numbers of bacterial in 0 ~ 20 cm and 20 ~ 40 cm soil significantly increased by 27.68% and 29.28%, and the copy number of fungi in 20 ~ 40 cm soil increased by 21.43%. The soil bulk density in 0 ~ 20cm soil was significantly reduced by 29.63% under ITO70% treatment. IRT treatment significantly increased the content of total potassium in 0 ~ 20 cm and 20 ~ 40 cm soil by 31.97% and 24.58%, and significantly increased the content of available potassium by 31.88% and 45.68%.
Conclusion Different fertilization of ecological rice-eel co-culture improves soil physicochemical properties and microbial community in paddy field compare with RT, and 70% fertilization combined with straw returning has the best improvement effect.