Mrvić V. author Jakovljević M. author Stevanović D. author Čakmak D. author text journal article 2007 The interactive relations of Al forms and the most important characteristics of Stagnosols were researched to diagnose which factors are the best to control the content of phytotoxic Al forms. The values of exchangeable Al (Al_KCl) range from 0.0 to 560.7 mg/kg and increase with depth. The variation of exchangeable Al is high and it depends on the changes of all forms of soil acidity and the degree of base cation saturation. Their relation is best described by a non-linear function. The contents of total Al and Al extracted by ammonium oxalate in dark (Al amorphous, Al_oxa) increase with depth, together with the increase of the content of clay particles. The values of Al extracted by sodium citrate/dithionite (Al crystalline, Al_dit), 0.5M CuCl₂ (Al_Cu) and 0.25M EDTA (Al_EDTA) are in good correlation and they predominantly depend on the parameters of soil acidity. The value of Al_Cu-Al_KCl (in eluvial horizons) is best represented by organically bound Al. Effects of the reserves of aluminium Al_dit, Al_Cu and Al_EDTA on the changes of exchangeable Al are higher (medium and high correlation), while the effects of the total Al and Al_oxa are lower. Stagnosol; soil; exchangeable Al; Al amorphous; Al crystalline; organic Al 10.17221/2303-PSE https://pse.agriculturejournals.cz/artkey/pse-200711-0003.php https://pse.agriculturejournals.cz/artkey/pse-200711-0003.php continuing 53 11 482 489 2007 12141178 periodical academic journal