The liquid obtained after anaerobic fermentation of pig manure (biofertilizer) from hoggery is beneficial for the supply of crop nutrients. This study was proceeded to the effect of irrigation by biofertilizer on crops. The irrigation area was set based on the amount of appropriate fertilization for nine crops in the crop fertilization manual (FI), and the application of chemical fertilizers were set as control area (CK). The results showed that the soil pH of eight crops in the FI area was generally higher than that in the CK area. As for the soil organic matter content, phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), manganese (Mn), copper (Cu) and zinc (Zn) in the most areas of crops were not really higher in the FI area than in the CK area which may be related to the different applied amount of fertilizer by farmers. Sodium (Na) content in all test areas before and after the experiment were all below 250 mg/kg. It showed that the irrigation of biofertilizer did not significantly increase the soil Na content and cause soil salinization. On the other hand, there were no significant increase in the Na concentration of nine crops after this experiment.

Keywords: circular economy, friendly environment, soil properties, plant nutrition, net zero emission