Abstract:

In order to clarify the effects of biogas slurry application on rice production and soil quality, this study conducted field experiments for 2 consecutive years. Three biogas slurry treatment groups were set up to explore the effects of biogas slurry and chemical fertilizer on soil nutrient indexes, heavy metals conent and rice yield. The results showed that the contents of organic matter, total nitrogen and organic nitrogen in the soil were increased by 7.55%-73.38%, 8.02%-86.10% and 3.80%-86.41%, respectively, and the increase rate of T2 was the largest. The biogas slurry treatment reduced the content of Cr、Ni、Cu、Zn、As、Pb and Hg in the soil. The T2 treatment had the highest rice yield, which increased by 13.2% compared with chemical fertilizer treatment, while the T3 treatment reduced the rice yield by 18.2%, while the T1 treatment had no significant effect on the rice yield. The combined application of biogas slurry and chemical fertilizer could improve soil fertility, promoted the improvement of soil environmental quality, and increased rice yield. In the later stage, it is necessary to further determine the optimal dosage and application scheme of biogas slurry and chemical fertilizer through experiments.

Key words: biogas slurry, rice, yield, heavy metals, combined application