Browse on keywords: crop rotation energy
Search results on 06/19/13
7662. Wright, A.T. and E. Coxworth. 1987. Benefits from pulses in the cropping systems of northern Canada. p. 108. IN: J.F. Power (ed.). The role of legumes in conservation tillage systems..
Investigated yield and N response in barley and wheat, 1 and 2 years after pulse crops of fababean, pea, and lentil. Overall yields were higher on fababean and field pea residues than lentils. Soil tests could not attribute yield differences among crop residues to differences in soil N levels at time of seeding. Nitrogen fertilizer equivalents for barley were 105, 85, and 50 lb N/ac for fababean, peas, and lentils. Legume residues influenced barley grain quality. In the second year following pulses, the dry matter yield, grain yield, and N uptake of wheat was 15% higher than in the continuous cereal sequence. Analysis of 3 completed rotation cycles showed that cropping sequences that included pulses were considerably more productive than the continuous cereal sequence in terms of net energy production and economic gross margin to cash costs. Field peas were the most effective first-year crop in terms of net energy production.
7770. Zentner, R.P., M.A. Stumborg, and C.A. Campbell. 1989. Effect of crop rotations and fertilization on energy balance in typical production systems on the Canadian prairies.. Agric., Ecosys., Environ. 25:217-232.
Non-renewable energy inputs, metabolizable energy output, and the energy efficiency of 10 spring wheat rotations were examined over 18 yr. Conventional tillage was used. Results showed total energy input per unit of land was lowest for the traditional wheat-fallow rotation (3482 MJ/ha), intermediate for N and P fertilized fallow-wheat-wheat (4470 MJ/ha), and highest for fertilized continuous wheat (7100 MJ/ha). Fuel accounted for 30-50% of the energy inputs, and fertilizer accounted for 15-49%. Pesticides were only 4-11%. Energy output to input ratios and the quantity of wheat per unit of energy decreased with cropping intensity. The average energy O/I was: F-W 3.6, F-W-W 3.3, cont. W 2.6. Rotations that included flax or cereal forage crops had the lowest energy efficiency.