改良剂对粘质潮土团聚体特征及分形维数的影响

Effects of Soil Amendments on Characteristics and Fractal Dimension of Clay Soil Aggregates

为评价复合功能改良剂（NSA）对板结土壤的改良效果,通过小白菜盆栽试验,研究NSA对滨州粘质潮土的理化性状、土壤团聚体数量、分布和稳定性的影响。结果表明,增施NSA可降低土壤容重、比重和pH值,提高土壤总孔隙度;施用NSA显著增加了0.5~1mm和0.25~0.5mm的团聚体含量,显著降低了〈0.05mm的团聚体含量,施用0.5%和1.0%的NSA后,土壤水稳性大团聚体总含量（R0.25）比CK分别显著提高67.14%和141.58%,NSA可将团聚体聚合成更大粒径来实现对土壤结构的改良;添加NSA使平均重量直径（MWD）和几何平均直径（GMD）显著提高,土壤不稳定团粒指数（ELT）显著降低;分形维数（D）随着NSA的添加而减少。施用NSA可促进土壤团聚体的形成,并提高其稳定性,对土壤结构具有显著的改善作用,这对进一步研制多功能的土壤改良剂提供了参考。

By taking clay soil in Binzhou as research objects,pot experiments were conducted in order to evaluate the effects of nutritive soil amendments on compacted soil.Soil bulk density,soil specific gravity,porosity and soil aggregate were investigated,and stability of soil aggregate were calculated to study the effects of NSA on characteristics and fractal dimension of clay soil aggregates.The result showed that NSA could decrease pH,soil bulk density and soil specific gravity,and increase porosity.NSA significantly increased the content of 0.5~1 mm and 0.25~0.5 mm soil aggregate,while significantly reduced the content of0.05 mm soil aggregate.The amount of water-stable macroaggregates（R0.25）of 0.5% NSA and 1.0%NSA were significantly higher than the control（CK）,with an increase of 67.14 % and 141.58%.With soil amendments application,larger soil aggregates were formed to improve soil condition.Mean weight diameter（MWD）,geometric mean diameter（GMD）and fractal dimension（D）were significantly higher than the control,and the soil unstable aggregate index（ELT）decreased with amount of NSA which was the lowest in T3 treatment.The results indicated that applying NSA could improve surface soil structures through increasing water-stable macroaggregates contents and stability.This research provides academic and instructive bases for developing soil amendments.