【摘 要】
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Simultaneous multi-element extraction has been increasing worldwide to improve soil laboratory testing quality and efficiency.This study sought to investigate t
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Simultaneous multi-element extraction has been increasing worldwide to improve soil laboratory testing quality and efficiency.This study sought to investigate the applicability of the Mehlich-1,Mehlich-3,and resin methods for simultaneous extraction of soil available P,K,Ca,and Mg as well as the effect of using conversion equations on nutrient recommendations for crops.Topsoil(0-20 cm)samples were taken from the most representative soil types used for crop production in southern Brazil with a wide range of chemical,physical,and mineralogical properties.Soil P,K,Ca,and Mg were simultaneously extracted using 1.0 mol L-1 KCI,Mehlich-1 and Mehlich-3 solutions,and membrane resin.The amounts of P extracted with the Mehlich-1 method were,on average,50% lower than those extracted with the resin and Mehlich-3 methods.However, the resin method extracted the lowest amounts of K,Ca,and Mg.The use of conversion equations was suitable and it did not affect negatively the K recommendations for crops grown on soils of southern Brazil.
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