Abstract:
Understanding the effects of food waste biogas residue composting and chemical amendments on soil aggregates composition of different particle sizes, stability, and organic matter distribution in relocation sites could provide primary data for improving soil quality and land utilization of food waste biogas residue composting. We analyzed the characteristics of soil aggregates distribution, stability of aggregates, and organic matter content in different particle sizes under treatments with different application amounts of food waste biogas residue composting, chemical amendments (β-cyclodextrin, calcium sulfate and ferric oxide were mixed at a mass ratio of 1:1:1), and control (100% soil). The results showed that 20% (soil: biogas residue composting=8:2) and 30% (soil: biogas residue composting =7:3) biogas residue composting significantly decreased the micro-aggregates content with the particle size of <0.106 mm and increased the large aggregates content with the particle size of 0.5-1.0 mm. All treatments significantly increased large aggregates content with the particle size of ≥2.0 mm, soil aggregate structure content, and mean weight diameter, but reduced the percentage of aggregate destruction. Among all the treatments, the effect of mixes application of 20% biogas residue composting and chemical amendments was the best. Biogas residue composting treatments significantly affected the distribution of organic matter in soil aggregates, with the strongest effect under 30% biogas residue composting treatment. Biogas residue composting treatments significantly increased soil organic matter content in all aggregates, with the maximal increase of organic matter content in soil micro-aggregates with the particle size of 0.106-0.25 mm. In conclusion, biogas residue composting could increase organic matter content of soil aggregates in different particle sizes, promote the formation of large soil aggregates, and improve the stability of aggregation. Specifically, the mixed application of biogas residue composting and chemical amendments performed better on soil improvement in relocation site.
探究厨余垃圾沼渣堆肥和化学改良剂对搬迁地不同粒径土壤团聚体组成及其稳定性和有机质分布的影响,可为土壤质量提升和沼渣堆肥土地利用提供理论依据。设置厨余垃圾沼渣堆肥不同施加量、化学改良剂(β-环糊精、硫酸钙和氧化铁按质量比1∶1∶1混合)及对照(100%土壤)处理,研究了不同处理土壤团聚体组成、团聚体稳定性及不同粒径团聚体有机质分布特征。结果表明: 与对照相比,20%(土壤∶沼渣堆肥=8∶2)、30%(土壤∶沼渣堆肥=7∶3)沼渣堆肥处理显著降低了<0.106 mm粒径的土壤微团聚体含量,增加了0.5~1.0 mm粒径的土壤大团聚体含量;各处理均显著增加了≥2.0 mm粒径的土壤大团聚体、团粒结构体含量和平均重量直径,降低了团聚体破坏率,其中20%沼渣堆肥和化学改良剂混施处理效果最佳。沼渣堆肥显著影响各粒径土壤团聚体有机质分布,30%沼渣堆肥处理对土壤团聚体有机质分布的影响最大;沼渣堆肥显著增加了各粒径土壤有机质含量,其中0.106~0.25 mm粒径的土壤微团聚体有机质增幅最大。综上,沼渣堆肥有助于增加搬迁地各粒径土壤团聚体有机质含量,促进土壤大团聚体的形成和提高团聚体的稳定性,且沼渣堆肥和化学改良剂混施对搬迁地土壤的改良效果更佳。.