煤基与生物基腐植酸配施对土壤结构改良的影响

为探究煤基腐植酸与生物基腐植酸混合对土壤结构的影响并筛选出一种效果最佳的混合比例，本研究采用土壤培养方法，通过将煤基腐植酸与生物基腐植酸按不同质量比设计成复合腐植酸改良半生土，以不施腐植酸为对照（CK），分析培养10、25、50 d时复合腐植酸对土壤团聚体、孔隙度等结构指标的影响。结果显示：土壤各项理化指标整体改良效果表现为50 d>25 d>10 d；土壤团聚体含量、平均质量直径随煤基腐植酸含量增加而增加，单施煤基腐植酸时最佳，培养50 d时土壤团聚体含量较CK组增加116.36%，平均质量直径较CK组增加了21.80%；比较发现，培养10 d时土壤总孔隙度、田间持水量随生物基腐植酸比例增大而增加，容重随之降低，而培养25 d和50 d时，总孔隙度和田间持水量则随煤基腐植酸比例增大而增加，容重随之降低；煤基和生物基腐植酸7∶3组合最佳，50 d时该组合土壤总孔隙度和田间持水量分别较CK组增加10.46%和43.52%，容重降低8.25%。研究表明，煤基腐植酸和生物基腐植酸均可有效改善土壤结构，当混合质量比为7∶3时效果最佳。该混合比例的复合腐植酸可综合生物基腐植酸和煤基腐...

Effect of combined application of coal-and bio-based humic acid on soil structure improvement

In this study, the soil incubation method was used to investigate the effect of mixing coal-based humic acid with bio-based humic acid on soil structure and to screen for an optimal mixture ratio. In this study, coal-based humic acid and bio-based humic acid were mixed at different mass ratios to form a composite humic acid to improve semi-arid soils. No humic acid was used as a control（CK）to analyze the effects of the composite humic acid on structural indices such as soil aggregates and porosity at 10, 25 d, and 50 d of incubation. The results showed that the overall improvement effect of each index was 50 d >25 d >10 d. The soil agglomerate content and average weight diameter increased with the increase of coal-based humic acid content, and was best when coal-based humic acid was applied alone. The soil agglomerate increased 116.36% compared with the CK group at 50 d of incubation and the average mass diameter increased by 21.80% compared with the CK group. In comparison, it was found that total soil porosity, and field water holding capacity changed significantly with an increase in the proportion of bio-based humic acid at 10 d of incubation, while the effect was stronger with an increase in the proportion of coal-based humic acid at 25 d and 50 d of incubation. The 7∶3 combination of coal-based humic acid and bio-based acid was optimal, and the total soil porosity and field water holding capacity of this combination at 50 d increased by 10.46% and 43.52%, respectively, and decreased by 8.25% in bulk density compared with the CK group. In a comprehensive analysis, both coalbased humic acid and bio-based humic acid could effectively improve soil structure, and the best effect was achieved when the mixing mass ratio was 7∶3. This composite humic acid mixing ratio can combine the advantages of bio-based humic acid and coal-based humic acid and provide technical support and scientific basis for the restoration of degraded soil.