ISSN:
1435-0661
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
,
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Triticum aestivum L.) harvest were determined in Bethany silt loam (fine, mixed, thermic Pachic Paleustoll). Treatments were moldboard plowing (MP) and no-till (NT) at two residue rates (0 and 4 Mg ha-1). Soil respiration was measured from 1 August to 30 September using closed chambers. Peak CO2-C flux densities reached 1.3 g m-1d-1 in NT for 2 d and stabilized at 0.4 g m-1d-1. The CO2-C evolution peaked at 4.1 and 2.9 g m-1d-1 in MP with and without buried residues, respectively. After 3 d, they decreased to a steady state of 0.4 g m-1d-1. Daily average temperatures in the 0- to 0.2-m depth were 0.5 to 3.4°C higher under MP than NT, increasing microbial adenosine triphosphate (ATP), biomass C, and CO2-C fluxes. The proportion of soil OC respired in the 60-d period was twice as great under MP than NT, accounting for 0.42 to 0.58% and 0.19 to 0.22%, respectively. After 11 yr, NT soil OC showed increases of 65, 17, and 7% over the MP for the 0- to 0.05-m, 0.05- to 0.1-m, and 0.1- to 0.2-m depths, respectively. Tillage and residue incorporation enhanced C mineralization and atmospheric fluxes, suggesting that tillage intensity should be decreased to reduce C loss.
Type of Medium:
Electronic Resource
Permalink