Leaching of plant nutrients from cultivated soils: I Leaching of cations

Abstract

Leaching of native and added basic cations was studied in a lysimeter experiment. The trial was carried out with three surface soil samples: sand, fine sand and sandy clay. The effect of the acidic precipitation on the leaching losses was studied by using 0.025 M sulfuric acid as irrigation solution. The cation concentration in the leachate seemed to be determined by the CEO of the soil sample. The relative and absolute leaching losses were lowest in the sandy clay and highest in the sand soil. Five percolations extracted most abundantly calcium and least abundantly sodium, the losses of magnesium and potassium were of about the same magnitude. In regard to cation reserves of the soils the relative amounts leached usually followed the sequence: Na >Mg≈ Ca>K. Fertilization seemed to promote the leaching of cations, especially that of soil calcium. Water extracted 10 to 37 % of added magnesium, but only 2 to 6 % of added potassium due to the effective retention. The acid in the irrigation water increased the losses of all cations studied, most drastically the losses of divalent ones.

Leaching of Phosphorus, Calcium, Magnesium and Potassium in Barley, Grass and Fallow Lysimeters

“…According to Hartikainen (1978b), the tendency for cations to be leached from different soils seems to depend on the cation exchange capacity of the soil. In somewhat acid mineral soils of Finland, the effective T. Yliiranta et al cation exchange capacity (CEC) appears to be most closely correlated with the clay content (Kaila, 1971).…”

Leaching of plant nutrients from cultivated soils: II Leaching of anions

“…Cations and anions are likely to be washed out in equivalent amounts. Comparing the sums of leached anion equivalents to the respective sums of the basic cations calculated from the analytical data from the previous work (Hartikainen 1978) it was found that the amounts of anions were always considerably lower than those of the cations. The chloride content was less than 1 meq in all the lysimeters and can be neglected.…”

“…In different soils it seems to correspond to the behaviour of cations (cf. Hartikainen 1978): leaching losses were lowest in the clay soil and showed a tendency to increase when soil material became coarser. However, phosphate makes a striking exception; the amounts washed out from the columns of sand and fine sand soils were at most about one tenth of the losses from the clay soil sample.…”

“…Their properties and the experimental design are presented in the previous work (Hartikainen 1978 The solutions percolated during twentyfour hours were measured and analysed for nitrate by using a specific electrode (Orion lonanalyzer meter). The average amounts of the total leachates collected were: 1330 ml from the sand, 1370 ml from the fine and and 1363 ml from the sandy clay soil.…”

Comparison of and correlation between the characteristics of agricultural topsoil and subsoil at the southern coast of Finland

“…The effects of fertilization on the nutrient content of the subsoil are difficult to study, because they require special arrangements. The results of leaching experiments carried out in fields and in laboratory indicate the movement of basic cations (Wiklander 1970, Hartikainen 1978 to be greater than that of phosphorus (Hartikainen 1978 b).…”