3类土壤改良剂对南繁育种区新垦耕地土壤质量与大豆生产力的影响OA

[Objective]To improve soil quality of newly reclaimed farmland in Nanfan China breeding base and clarify the soil fertility improvement mechanisms of three amendments,including soil conditioners,biofertilizers and microbial inoculants.[Method]A field plot experiment was conducted on newly reclaimed ferric lateritic soil,and using a single-factor randomized block design with seven treatments:CK,two soil conditioners at 750 kg/hm2(T1,T2),two biofertilizers at 1 200 kg/hm2(T3,T4),and two microbial inoculants at 75 kg/hm2(T5,T6).The effects of three types of soil amendments on soil physicochemical properties,total soil microbial biomass,and soybean productivity were systematically evaluated.[Result]Compared with CK,T1 and T2 significantly increased soil available phosphorus content by 114.65％and 187.50％at sowing and by 68.32％and 102.66％at harvesting,and significantly increased soil pH by 8.56％and 9.48％at harvesting.T3 and T4 significantly increased soil organic matter content by 8.75％and 8.32％at sowing and 7.89％and 9.87％at harvesting,and significantly increased soil inorganic nitrogen content by 154.28％and 172.35％at harvesting.T5 and T6 significantly increased soil available potassium content by 42.63％and 46.15％,available phosphorus content by 52.70％and 79.45％,and soil nitrate nitrogen content by 106.35％and 86.27％at harvesting.Compared with CK,T1 and T2 significantly increased total soil microbial biomass at harvest by 158.50％and 237.20％relative to the sowing stage,while T3 and T4 significantly decreased it by about 31.83％and 32.10％,and T5 and T6 significantly decreased it by over 72.01％and 71.69％.Compared with CK,T3 and T4 significantly increased soybean economic yield by 33.64％and 41.23％,and T5 and T6 significantly increased it by 34.59％and 31.28％.Among all treatments,T6 exhibited the most significant increase in nitrogen and phosphorus use efficiency compared with CK,reaching 19.76％and 24.07％respectively.Correlation analysis showed that soybean economic yield exhibited an extremely strong and highly extremely significant positive correlation with nitrogen and phosphorus use efficiency.Total microbial biomass was significantly correlated with inorganic nitrogen content,but showed no direct relationship with total or aboveground soybean biomass,confirming that soil microorganisms primarily influenced economic yield indirectly by regulating nutrient transformation.[Conclusion]Biofertilizers demonstrate outstanding advantages in enhancing organic matter and sustaining nitrogen supply,soil conditioners are highly effective in adjusting pH and rapidly activating soil phosphorus,while microbial inoculants excel in promoting late-stage potassium release and nitrification at harvesting.