Effects of four annual applications of manure on Black Chernozemic soils

摘要

The influence of four annual applications of cattle and hog manure on soil pH, electrical conductivity (EC), sodium adsorption ratio (SAR), organic carbon, bulk density, aggregation, aggregate stability, crust strength, and water infiltration was investigated at two field sites, Burr and Dixon, in Saskatchewan under canola-wheat-barley-canola crop rotation. The average annual precipitation of these sites over the 4-year period was 400 mm. Manure application rates were 7.6, 15.2, and 30.4 Mg/ha (dry basis) for the cattle manure and 37.5, 75.1, and 150.2 m~3/ha for the hog manure. Cattle manure increased the EC of the Dixon soil from 0.30 to 1.60 dS/m and the aggregate stability of the Burr soil from 0.75 to 0.84 Hog manure reduced the pH of the Burrsoil from 8.0 to 7.6 and the crust strength from 3 to 0 kPa. Cattle and hog manure increased the SAR by 148 - 354% and decreased the bulk density and aggregate size by 8 - 9% and 30 - 40%, respectively, but did not significantly affect the total organiccarbon content. Cumulative water infiltration tended to increase with manure application but the increase was not significant. Overall, the effect of manure application on the soil chemical and physical properties after four annual applications were relatively small and variable suggesting that several years of repeated application may be required to produce changes in soil properties that would significantly influence soil productivity.