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Updated: Jul 10, 2026

10:19
A CO2 Concentration Gradient Facility for Testing CO2 Enrichment and Soil Effects on Grassland Ecosystem Function
Published on: November 21, 2015
Labeled Oxygen: Increased Diffusion Rate through Soil Containing Growing Corn Roots
Abstract:
The diffusion of oxygen labeled with oxygen-18 through cores of wet soil increased significantly when roots of growing corn seedlings penetrated the cores. The increase was small or absent when roots grew through a layer of soft wax or a layer of water-saturated 0.5-mm glass beads, indicating that the diffusion increase was a joint effect of the roots and airfilled pores in the soil. A possible mechanism is suggested.
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