| Studies of amino acid composition of soil organic matter extracted from 10 Iowa surface soils and from surface soils of two long-term rotation experiments showed that, with the exception of asparagine plus aspartic acid and glutamine plus glutamic acid, the other 13 amino acids, expressed as percentages of total amino acid extracted, were very uniform among the soils. The total amino acid extracted was significantly correlated with organic C (r = 0.79;A simple and precise method for assay of aspartase activity in soils was developed. It involves determination, by steam distillation, of the NH;Analysis of 171 Iowa surface soils showed that the amounts of fixed NH... |
