Browse on keywords: fertility Alberta
Search results on 12/08/13
3373. Janzen, H.H.. 1987. Soil organic matter characteristics after long-term cropping to various spring wheat rotations.. Can. J. Soil Sci., 67:845-856.
Various spring wheat rotations with and without perennial forages on total and mineralizable soil organic matter contents. The organic C and N contents of soil after 33 yr of cropping were highest in treatments continuous W and FWWAAA, and decreased with increasing frequency of fallow in the rotation. The inclusion of the perennial forage in the rotation did not increase organic C and N levels above those abserved in the continuous wheat treatment. It was concluded that inclusion of perennial forages in spring wheat rotations for the purpose of enhancing soil fertility and organic matter levles was not justified under semi-arid conditions.
4845. Newton, J.D.. 1954. Microbial maintenance of nitrogen in western Canada's grey wooded, black earth, and brown prairie soils.. Trans. 5th Intl. Congress of Soil Sci. Vol. 3:76-87.
Soil nitrate levels were higher for 3-4 years after alfalfa than after grass. Legumes responded to sulfur additions. Non-symbiotic N fixation was felt to account for significant N increases in lab studies with various soils. Maintenance of long-term yields was helped by heavy additions of straw.
9690. Malhi, S.S., M. Nyborg, D.R. Walker and D.H. Laverty. 1984. Fall and spring soil sampling for mineral N in northcentral Alberta.. Can. J. Soil Science 65:339-346..
The timing of soil sampling for mineral N was investigated by sampling in fall and in spring from the 0-30 cm depth in 100 field experiments. On the average of the 100 experiments, the NO3-N in soil increased from 16 kg N/ha in the fall to 34 kg N/ha in spring and the mineral N in soil increased from 28 kg N/acre in fall to 49 kg N/ha in spring. Soil test programs in the Prairie Provinces are based primarily on field experiments with only spring sampling, while farm smapling is mostly conducted in the fall. At least in north-central Alberta, fall sampling for soil test for NO3-N should be restricted to the late fall and probably an adjustment to N recommendations should be made for the smaller amounts of NO3-N found in fall rather than spring.