生物炭-菌剂-复合肥配施对花椒土壤理化性质的影响OA

To investigate the effects of combined applications of biochar(B),microbial agent(M),and compound fertilizer(F)on the physicochemical properties,fertility,and their interactions in Zanthoxylum bungeanum soil.Soil bulk density,pH value,organic matter,total phosphorus,total potassium,alkali-hydrolyzable nitrogen,available phosphorus,and available po-tassium were determined.The results showed that the combined application of biochar,microbial agent,and compound fertil-izer significantly reduced soil bulk density.Except for the B3M3F2 treatment,the pH value was significantly increased in all other treatments.The regulation effect on organic matter was differentiated,with the high biochar treatment(B3)reducing it by 35.8%.The highest alkali-hydrolyzable nitrogen content was found in the low-rate treatment(B1M1F1).Phosphorus regula-tion was dose-dependent:low biochar combined with high microbial agent(B1M3F3)promoted total phosphorus accumulation,medium biochar with low microbial agent(B2M1F2)increased available phosphorus,while high biochar(B3)induced phospho-rus fixation due to C/P imbalance.An appropriate amount of biochar(B1/B2)combined with microbial agent increased total po-tassium by 49.3%,whereas high biochar(B3)inhibited potassium activation.Statistical analysis indicated that total phospho-rus(CV=47.45%)and available potassium(CV=42.59%)were the most sensitive to treatment interactions.The microbial agent significantly increased available potassium(R=261.89),while biochar played a prominent role in regulating alkali-hydrolyzable nitrogen(R=78.06)and total phosphorus(R=0.33).Available phosphorus showed extremely significant posi-tive correlations with available potassium,organic matter,and pH value;organic matter was extremely significantly positively correlated with alkali-hydrolyzable nitrogen and total phosphorus.PCA revealed that the first three principal components cu-mulatively explained 80.57%of the variance;the ck treatment clustered distinctly apart from other treatments.The B3M3F2 treatment clustered significantly in the positive region of PC1,while the B1M3F3 treatment clustered significantly in the posi-tive region of PC2.In conclusion,the combined application of biochar and microbial agent can effectively activate phospho-rus and potassium nutrients and increase organic matter.Compound fertilizer should be combined with biological regulators to achieve synergistic effects,but excessive application may lead to apparent saturation and microbial inhibition.