Premium
Toxic Metals in Acid Soil: I. Estimation of Plant‐Available Aluminum
Author(s) -
Hoyt Paul B.,
Nyborg Marvin
Publication year - 1971
Publication title -
soil science society of america journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.836
H-Index - 168
eISSN - 1435-0661
pISSN - 0361-5995
DOI - 10.2136/sssaj1971.03615995003500020020x
Subject(s) - lime , hordeum vulgare , chemistry , soil water , brassica , soil ph , saturation (graph theory) , base (topology) , aluminium , greenhouse , horticulture , mineralogy , agronomy , poaceae , mathematics , soil science , metallurgy , environmental science , biology , materials science , mathematical analysis , organic chemistry , combinatorics
Exchangeable Al and 0.01 M CaCl 2 ‐soluble Al were measured in 40 acid surface soils by Clark's procedure for corrected lime potential and exchangeable cations, and by a modified procedure which was developed here. In the modified procedure, 0.01 M CaCl 2 ‐soluble Al was extracted by using 16 hr of shaking instead of 5 days, and exchangeable Al was extracted with 1 N KCl for 2 min instead of with 2 N NaCl for 16 hr. Good agreement was given with the theoretical relationship between corrected lime potential and percent base saturation of the permanent charge sites by both the original and modified procedures. Aluminum extracted by the two procedures and also that extracted by three other methods were then assessed for their availability to plants grown on the soils in a greenhouse study. Criteria of plant‐available Al were the yield responses to liming by barley ( Hordeum vulgare L.), turnip rape ( Brassica campestris L.), and alfalfa ( Medicago sativa L.), and the Al concentration in alfalfa grown on the unlimed soils. Exchangeable Al and 0.01 M CaCl 2 ‐soluble Al measured by Clark's and the modified procedures were all closely correlated with the criteria of Al availability. Aluminum extracted by 1 N NH 4 OAc (pH 4.8), 1 N NH 4 OAc (pH 3), or 0.002 N HCl methods were not so closely correlated with the criteria. The use of extractable soil Al for the diagnosis of the need for liming is discussed.