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文獻(xiàn)名：Evaluation of aggregate stability of Haplic Stagnosols using dynamic light scattering, phase analysis light scattering and color coordinates 

 

作者： Zinaida Artemyeva, Anna Zigova, Natalia Kirillova, Martin Š?astný, Ond?ej Holubík & Vilém Podrázský

Department of Biology and Biochemistry of Soils, V.V. Dokuchaev Soil Science Institute, Moscow, Russia

 

摘要：Dynamic light scattering and phase analysis light scattering have been used to study organo-clay complexes and aggregate stability of Haplic Stagnosols depending on land use. The study of agricultural soils afforested for 45 years showed that the value of the effective diameter of organo-clay complexes slightly decreased compared to that in arable soil but remains still higher than that in the forest soil. Multiple linear regression statistical models were developed to predict the effective diameter of the particles. The best model (r = 0.95), where all parameters were significant (P < 0.05), included the clay content, clay carbon concentration, total iron (Fet) and soil color coordinates (L*, a*, b*). In the upper horizons, the effective diameter depends on the organic matter content, whereas iron oxides with surfaced position play the main role in the underlying horizons. Intensive tillage moves the colloidal system to coagulation and after withdrawal of arable Haplic Stagnosol from the agricultural production, the colloidal system tends to restore its peptization stability. However, it should be noted that the afforestation period (45 years) of arable Haplic Stagnosols is not enough for a full recovery of organo-clay complexes peptization stability.