Crop Residue Management Practices, and N and P Fertilizer Effects on Crop Response and on Some Physical and Chemical Properties of a Black Chernozem Over 25 Years in a Continuous Wheat Rotation

Abstract

. 1986. Crop residue management practices, and N and P fertilizer effects on crop response and on some physical and chemical properties of a Black Chernozem over 25 years in a continuous wheat rotation. Can. J. Soil In the Black soil zone ofthe Canadian Prairies seedbed preparation is important for handling crop residues from high yields and for incorporating herbicides and fertilizers into soil in the fall or prior to seeding in spring. There are numerous tillage implements available to the producer for this operation. The question often arises as to the relative merits and demerits of using these implements, especially with respect to their effect on yield and on soil quality. A25-yr continuous spring wheat study was carried out at Melfort, Saskatchewan, in a splirplot design. The main plots were: four fall tillage implement treatments (plow, heavy duty cultivator, one-way disc and double disc), chopped straw in the fall and spring burn of straw. Four rates of fertilizer (0/0, 5/10, 22.5110 and 45l10 kg ha-' N/kg-' 6a-t P) were subplots from 1959 to 1977; the fertilizer rates were doubled for 1978 to I 983 . The results showed that there was no significant effect of tillage on yield but there was a significant fertilizer by tillage interaction. The spring burn treatment gave the highest yield (2073 kg ha-t; and the plow treatment the lowest yield (1963 kg ha-'). Fertilizer increased yields when moisture was adequate and either had no effect or depressed yields when precipitation was low. Only the plow treatment caused a loss of organic C and N. All tillage treatments increased the erosive fraction of the soil (fraction <0.83 mm) compared to the chopped straw and spring burn treatment. The application of the 90120 kg ha-r rate of N and P fertilizer decreased the proportion of soil aggregates <0.83 mm. There was no significant effect of tillage treatment on soil moisture conserved over the winter. There also was no tillage effect on NOr-N in the soil measured in the spring, but burning caused a significant increase in sodium bicarbonate-soluble P. The chopped straw treatment was concluded to be the best choice because the unincorporated residues will protect the soil best through the fall and winter and it is the easiest to implement. Where herbicides or fertilizers need to be fall-incorporated, any of the mechanical tillage implements except the plow should be equally suitable.

Effect of crop rotations and fertilization on soil organic matter and some biochemical properties of a thick Black Chernozem

“…At Melfort, fertilizer did not affect c€real straw/grain ratio which was 1.5/l (Nuttall et al 1986). Root/straw ratio for wheat assumed to be 0.59 (Campbell et al 1977a).…”

The influence of management on soil loss and yield of wheat in Chernozemic and Luvisolic soils

“…Lower soilerosion losses under CW than under WWF or WF may be associated with annual inputs of plant residues and the number of tillage operations used for weed control and seedbed preparation. The amount of above-ground plant residues returned to the soil at harvest was estimated by multiplying grain yield by 1.5 (Nuttall et al 1986)' Based on this equation, the average arnount of straw refurned annually was higher under CW (194i kg ha-l) than under W.WF (1603 kg hi-r) or \ fF (1367 kg hrl). An exponential function with negative slope described the effect of straw addition on rate of soil erosion (Fig.…”

Effects of Short-term Tillage of a Long-term No-Till Land on Available N and P in Two Contrasting Soil Types

“…However, in our study, RT and SRet did not show any significant effect on residual nitrate-N in soil at both sites compared to the corresponding NT and SRem treatments after 32 years. Similarly, earlier studies in Saskatchewan (Nuttall et al, 1986) and Alberta (Malhi et al, 2006Malhi & Lemke, 2007) have also shown no effect of tillage or straw management on residual soil nitrate-N. This lack of difference in residual nitrate-N in soil due to RT or SRet in this study could be due to uptake of all mineralized nitrate-N by crops in the growing seasons, resulting in little or no additional residual nitrate-N in soil after harvest compared to NT, as evidenced by greater crop yield and N uptake with RT and SRet than corresponding NT and SRem treatments (Malhi et al, 2011b(Malhi et al, , 2015.…”