Permafrost

signifies that the diffusion action of solute movement prevail against the convection. The
redistribution of SO4 2- after freeze is not apparent, mainly due to the high amount of fixation by
soil through static electricity adsorption or exchange adsorption of ligand. The redistribution
extent shows light increase with the increase of the concentration of solution input, but the
moving direction of SO4 2- is not certain for the specimen with a high concentration of 50‰, this
can be explained by the comprehensive action of convection and diffusion.
(2) For the specimens put with KH2PO4 solution: water soluble phosphorus show obvious
transport after freeze in the direction of the water transport when the input concentration is
higher (35‰ and 50‰), but no apparent trans port for lower concentration, imply that high
amount of phosphorus is adsorbed or fixed by soil through chemical action with calcium,
magnesium, iron, aluminium and manganese etc. and becoming unsolvable matter. The
redistribution of total phosphorus is not obvious either, means a big portion of it is in fixation. A
big amount of water soluble kalium is adsorbed by the soil too, because only in the specimen
with high concentration of 50‰ there exist obvious transport of it toward the cold side same as
the water transport direction. The redistribution of total kalium show no certain tendency, the
reason is not clear, can be preliminary estimated as the different temperature, ice content and
unfrozen content etc. make the amount of fixed K + different along the soil column.
(3) For the specimens put with KCl solution: the redistribution Cl - is obvious for any specimen
with different input concentration, the movement direction of Cl - is same to the transport
direction of water during freezing, implies that the fixed portion of Cl - is small, and the
convection is prevailing. The redistribution of K + is obvious for any specimen with different
input concentration too, the movement direction of K + is same to the transport direction of
water during freezing, implies that the fixed portion of K + is small too, and the convection is
prevailing. Compared to the specimens input with KH2PO4, KCl has a smaller molecular weight,
at the same gravity percentage, the equivalent concentration or mole concentration of KCl is
much higher than KH2PO4, therefore even at a low gravity concentration, the amount of K + may
pass maximum fixation amount of it by the brown soil used in this study, and there exist much
dissolved K + in the soil solution. The redistribution of total kalium show no certain tendency
either, and the reason is not clear, can be preliminary estimated as the different temperature, ice
content and unfrozen content etc. make the amount of fixed K + different along the soil column
too.
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