Verlan L. Cochran

Learn More
Increasing concentrations of methane (CH4) in the atmosphere are projected to account for about 25% of the net radiative forcing. Biospheric emissions of CH4 to the atmosphere total approximately 400 Tg C y-1. An estimated 300 Tg of CH4-C y-1 is oxidized in the atmosphere by hydroxyl radicals while about 40 Tg y-1 remains in the atmosphere. Approximately 40(More)
Three mollisols, typical of the Palouse winter wheat region of eastern Washington and northern Idaho, were analyzed for microbial biomass, total C and total N after 10 years of combined tillage and rotation treatments. Treatments included till, no-till and three different cereal-legume rotations. All crop phases in each rotation were sampled in the same(More)
C and N mineralization potentials were determined, in a 12-week laboratory incubation study, on soil samples obtained from recently cleared land which had been cropped to barley for 4 years (field soils) and from nearby undisturbed taiga (forest soils). Treatments for the cropped soils were conventional and no-tillage with and without crop residues removed.(More)
 Migratory geese affect agricultural production by removing biomass and by depositing fecal nutrients. This study used 15N as a tracer to examine the quantitative effects of goose fecal N contributions on agricultural production. Barley (Hordeum vulgare cv. Datal) was grown for the production of 15N-labeled grain and straw. Two Canada geese (Branta(More)
 We studied the effects of a saprophytic lignin-decomposing basidiomycete isolated from plant litter on soil aggregation and stabilization. The basidiomycete produced large quantities of extracellular materials that bind soil particles into aggregates. These binding agents are water-insoluble and heat-resistant. Water stability of aggregates amended with(More)
Green manures (GM) may offset inorganic N needs and improve soil quality. Study objectives were to determine effects of green manure on soil-N fertility, water use, soil quality, and yield of spring wheat (Triticum aestivum L.). On two treatments, lentil (Lens culinaris Medikus cv. Indianhead) was green manured in a green manure–spring wheat rotation.(More)
The mass loss and N dynamics of barley stems and leaves, placed on the soil surface or buried, were examined over two summers. There was little difference in mass loss or N dynamics in straw placed 7.5 or 15 cm deep. However, the surface straw lost mass much more slowly and immobilized more N for a longer time than the buried straw. Filter paper had a slow(More)
Large-scale argicultural development in high latitude regions could lead to large losses of soil C due to accelerated decomposition. Changes in decomposition rates of forest floor material upon land clearing in interior Alaska were simulated by measuring, over a 2-year period, changes in mass, cellulose, lignin, and N of forest floor materials and in mass(More)
Published in Agron. J. 103:1292–1298 (2011) Posted online 13 Jun 2011 doi:10.2134/agronj2010.0410 Copyright © 2011 by the American Society of Agronomy, 5585 Guilford Road, Madison, WI 53711. All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying,(More)
An understanding of the C and N dynamics of crop residues is important for efficient nutrient management. The present experiment was conducted to determine the rate of mass and N loss from alfalfa, faba bean, barley, and rape crop residues in a subarctic agricultural soil. Mass, C, and N losses were measured from residues contained in mesh bags and placed(More)