Fig. 4
Effect on soil chemical properties and enzymes after BIO application in 2021. A: PCA analysis of chemical properties of the surface soil layer (0-15 cm) from the BIO-treated; B: The activity of soil acid phosphatase activity (S-ACP) was not influenced by BIO-treatment compared to CK; C: BIO influence on soil urease activity (S-UE); D: the soil β-glucosidase (S-β-GC) activity was obviously influenced under BIO-treatment. Values shown here represent the average of three repetitions (n = 3). Means with different letters represent significant differences at p < 0.05. BIO_50_2: 750 kg/hm2 BIO-treated soil in 2021; BIO_100_2: 1500 kg/hm2 BIO-treated soil in 2021;BIO_200_2: 3000 kg/hm2 BIO-treated soil in 2021; BIO_400_2: 6000 kg/hm2 BIO-treated soil in 2021; BIO_800_2: 12,000 kg/hm2 BIO-treated soil in 2021; HPS: herbicide- treated soil in 2021; CBF: common bio-fertilizer in 2021; CBFS: common bio-fertilizer-treated soil in 2021, and CK: untreated control soil in 2021