THE EFFECT OF CELLULOSE XANTHATE AND POLYVINYL ALCOHOL ON INFILTRATION, EROSION, AND CRUSTING AT DIFFERENT SODIUM LEVELS

Abstract

In laboratory experiments, we evaluated the influences of cellulose xanthate and polyvinyl alcohol (PVA) on water infiltration, erosion and crusting of soils at exchangeable sodium fractions (ENa) of 0, 0.05, and 0.10. Three soils were treated with the chemical amendments at a rate of 0.5 g.kg−1 of dry soil; a set of untreated soils was prepared for comparison. The soils were placed at a 14% slope and subjected to simulated sprinkler irrigations with saline and then nonsaline waters. Hydraulic conductivity (K), monitored at intervals, decreased after irrigations of treated and untreated soils. Fallbrook soil exhibited 20 to 150% increases in K after both treatments; after irrigation, K of Fall-brook soil decreased, but remained above levels of untreated soil. K of the other soils was not significantly improved by either treatment. ENa level had no influence on the effectiveness of either amendment to improve K. Erosion, measured from 3 to 54 mg of solid per ml of runoff from untreated soils, was nearly eliminated by both amendments on all soils during both saline and nonsaline irrigation regardless of ENa level. Crust strength was reduced 30 to 60% by xanthate and 0 to 30% by PVA relative to untreated soil and exhibited no correlation with ENa.