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土壤性质,诸如pH,有机质含量和粘土矿物等都可影响微量元素的有效性。耕作方法可以改变某些土壤性质。本研究试图确定耕作措施对各种土壤组分中Mn、Cu、Fe和Zn分配的影响。土样采自长期(8年)耕作试验田0—2cm土层。处理设:免耕少耕(仅秋耕)和常规耕作(春秋耕翻)。土壤样品经连续分离后,在代换态,有机态,氧化锰,无定形氧化铁,结晶氧化铁和残余等组分中测定Mn、Cu、Fe和Zn。免耕处理的双酸溶性P和Zn,有机质含量和阳离子代换量高于其他耕作处理。耕作对各组分中Mn和Fe分配的影响大于Zn和Cu。免耕与少耕或常规耕作相比,降低了代换态和无定形氧化铁组分中的Mn,而提高了有机态中的Mn。同时免耕处理中代换态和有机态组分中的Fe也较高,而无定形氧化铁和残余组分中的Fe较常规耕作低。由于免耕,Mn和Fe出现了从氧化物和残余形态向更有效的代换态或有机态的转化。
Soil properties, such as pH, organic matter, and clay minerals, can affect trace element effectiveness. Tillage methods can change some soil properties. This study sought to determine the effects of tillage practices on Mn, Cu, Fe and Zn distribution in various soil fractions. Soil samples taken from the long-term (8 years) tillage test field 0-2cm soil layer. Processing facilities: no tillage and less tillage (only autumn) and conventional farming (spring tillage). Soil samples were continuously separated and Mn, Cu, Fe, and Zn were measured in the components of substitutional, organic, manganese oxide, amorphous iron oxide, crystalline iron oxide and residual. Double acid-soluble P and Zn in no-till treatment had higher organic matter content and cation exchange capacity than other tillage treatments. The effect of tillage on the distribution of Mn and Fe in each component was greater than that of Zn and Cu. Compared with tillage or conventional tillage, no-tillage reduced the Mn in the substitutional and amorphous iron oxide components and increased the Mn in the organic state. At the same time, the Fe in the substitutional and organic components of no-till treatment was also higher, while that of amorphous iron oxide and residual components was lower than conventional tillage. Due to no-till, Mn and Fe appear to shift from oxides and residual forms to more efficient substitutions or organic conversions.