Predicting Optimum Depth of Profile Modification by Deep Plowing for Improving Saline-Sodic Soils

Rasmussen, W.W. and McNeal, B.L. (1973) Predicting Optimum Depth of Profile Modification by Deep Plowing for Improving Saline-Sodic Soils. Soil Science Society of America Proceedings. 37(3):432-437.

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Abstract

A previously developed procedure for predicting the effect
of mixed-salt solutions on soil hydraulic conductivity (HC) was
used to predict the relative hydraulic conductivity (RHC) of
separate soil horizons from saline-sodic soils, using a standard
low-salt solution following a standard high-salt solution at a
fixed exchangeable-sodium level. These values were then used
to predict the RHC of mixtures of the same horizons simulating
profiles modified to various depths by deep plowing. Weighting
RHC values for individual horizons by the depth fraction of
each horizon in the soil mixture provided RHC values of proper
magnitude, except when large proportions of calcareous subsolum
material were incorporated into the mixture. Results
were improved by multiplying calculated RHC values for each
soil mixture by the initial HC of the mixture. This corrected
for the filling of conducting pores in more permeable horizons
by smaller particles from less permeable horizons during the
mixing process (analogous to particle dispersion and pore sealing
during the leaching of saline-sodic soils). Soil constants
determined for the mixed soils permit the prediction of the
response of these soils to any other exchangeable sodium levels
or soil solution concentrations of interest. Results were consistent
with lysimeter and field plot observations on the same
soils, including deep plowing trials.

Item Type:	Article
NWISRL Publication Number:	0261
Subjects:	Soil > Tillage Soil > Chemistry Mass Import - autoclassified (may be erroneous)
Depositing User:	Dan Stieneke
Date Deposited:	20 Nov 2010 21:51
Last Modified:	16 Feb 2017 22:17
Item ID:	243
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/243