- Dec. io, 1917 
Movement of Soluble Salts through Soils 
547 
The chemical studies show that the addition of soluble salts to a given 
region of the soil results in changes of the composition of the soil solution 
which may not be confined to the soil mass receiving the application. 
It seems that such conditions are of far-reaching importance in connec¬ 
tion with the results obtained from the use of soluble-fertilizer salts, as 
well as attempts to bring about a so-called balanced soil solution. Inas¬ 
much as soils undoubtedly vary with respect to the action that takes place 
when they are treated with various soluble substances, it does not seem 
possible to work out a balanced soil solution by studying a few soils. 
CONCLUSIONS 
(1) The results presented show that soluble salts move from regions 
of high to lower concentration in moist soils, the rate being rather rapid, 
and therefore do not long remain localized, as reported by earlier investi¬ 
gators. Moreover, the rate of movement is affected by the water content 
of the soil and the mass of salt present. 
(2) Where moisture is being lost by evaporation, the upward move¬ 
ment is more rapid than the downward translocation in heavier soils; 
but in case of sands the downward translocation is indeed slight, thus 
indicating that soluble salts, such as sodium nitrate, are more likely to 
be lost by upward movement to the surface of sandy soils during a 
drought than in case of heavier soils. 
(3) Chemical studies show that as the salts move through the soil 
mass the solution in the various layers of soil changes in composition. 
Such changes, it seems, have an important bearing upon the results to 
be obtained from the use of fertilizer salts, especially upon attempts to 
determine a so-called balanced soil solution by studies confined to a 
limited number of soils. 
(4) The indications are that the translocation of soluble salts in soils 
is brought about by means of diffusion, by reactions that take place in 
the soil, and by moisture movements. 
(5) Field and laboratory experiments in progress should throw addi¬ 
tional light upon moisture’ movement in different soil classes, as well 
as the upward movement from the subsoil of substances in solution. 
23717°—17 - 2 
