Browse on keywords: fertility tillage soil quality
Search results on 12/16/18
1854. Emmond, G.S.. 1971. Effect of rotations, tillage treatment and fertilizers on the aggregation of a clay soil.. Canadian J. Soil Science, 51:235-241.
Soil aggregation was lowest in a wheat-fallow rotation and increased in other fallow-grain rotations with the second, third and forth crops after the fallow year. The best aggregation was under continuous wheat. Rotations containing hay crops increased aggregation significantly. Tillage treatments affected soil aggregation in the following order: green manure crop plowed under> cultivated with trash cover> crop residue plowed under > cultivated with crop residue burned off = crop residue disked in. Fertilizer (11-48-0) increased aggregation except where crop residue had been removed. Barn manure increased soil aggregation. T: Effect of barn manure and crop sequence on soil aggregation. Effect of 5 tillage treatments on soil aggregation.
4807. Nelson, A.L.. 1950. Methods of tillage for winter wheat.. WY Agr. Expt. Sta. Bulletin 300.
Fallow/winter wheat production decreased soil N by 33% in the top 6" over 35 years. Continuous cropping lost 24% of the soil N. Crop rotations using green manure every 4th year did not decrease the loss of soil N. Average winter wheat yields (bu/ac) over 34 years for 3 rotations were: oats/rye(GM)/winter wheat/corn - 12.9; oats/peas(GM)/winter wheat/corn - 12.7; fallow/winter wheat - 13.7; oats/corn/winter wheat/rye - 13.2; oats/corn/winter wheat/peas - 14.1; oats/corn/winter wheat/fallow - 13.2. It was observed that green manure took years to break down. Tillage with an eccentric one-way increased winter wheat yields 2 bu/ac over 10 years compared to plowing. The eccentric one-way conserved moisture. Continuous cropping resulted in winter wheat yields 55% of biennial yields following fallow. Soil moisture was 3-4% lower in October after continuous cropping versus fallow.
5649. Rasmussen, P.E. and C.R. Rohde. 1988. Long-term tillage and nitrogen fertilization effects on organic nitrogen and carbon in a semi-arid soil.. Soil Sci. Soc. Am. J. 52(4): 1114-1117.
A 44 year experiment of wheat-fallow rotations in the Pacific Northwest. Main treatments were 3 primary tillage systems, one conventional and two stubble mulch. Subplots were 6 different N treatments. Organic N and C in the top 75mm of soil were 26 and 32% greater in the stubble mulch systems than the conventional system. Stubble mulch plots contained 245 kg more N/ha than the conventional plots. In all treatments 18% of applied N was incorporated into the organic fraction. N transformations were the same for stubble and conventional treatments. T: Organic N and C at different depths as effected by tillage method and N fertilization. Tillage and N effects on organic N in upper 225 mm of soil. Tillage and N effects on organic C in upper 225 mm of soil.
5659. Rasmussen, P.E. and C.R. Rohde. 1989. Soil acidification from ammonium-nitrogen fertilization in moldboard plow and stubble-mulch wheat-fallow tillage.. Soil Sci. Soc. Am. J. 53(1):119-122..
Change in soil pH in relation to applied N was determined for one conventional and two stubble-mulch tillage treatments. Acidifying effects were concentrated in the top 7 cm of the stubble-mulched soil, but distributed to 22 cm or more with moldboard plowing. The rate of pH decline was greater for moldboard plowing than stubble-mulching. T: Long-term N fertilization effect on pH in the upper 45 cm of soil under different tillage systems. Linear relationship between applied N and soil pH, as affected by tillage.