Ja. Quaggio et al., SOYBEAN RESPONSES TO LIME AND GYPSUM AND ION LEACHING INTO THE SOIL-PROFILE, Pesquisa agropecuaria brasileira, 28(3), 1993, pp. 375-383
An experiment was carried out in order to determine soybean responses
to limestone and gypsum and to evaluate ion leaching along the soil pr
ofile. A randomized complete block design was used, with four replicat
ions, in a split-plot experiment. The treatments consisted in incorpor
ation into the plow layer of 0, 3, 6 and 9 t/ha of limestone (main plo
ts) and of gypsum (subplots). The results showed high soybean response
to lime and no response to gypsum. Liming also increased the leaf con
tents of N, P, and K. Liming increased the contents of Ca and Mg down
to the 40-60 cm soil layer. Gypsum increased Ca and Mg leaching along
the soil profile, but its effects were short-lived. Ca and S-SO4 appli
ed after gypsum had leached beyond the 40-60 cm soil layer 18 months a
fter application. Gypsum also increased Mg losses by leaching.