Air pressure fluctuations in a prairie soil

摘要: The influence of air convection on soil aeration has not been investigated in great detail. A study was conducted to measure pressure changes by depth the first 2 m a prairie that known for its denitrification properties. An absolute probe used fluctuations at surface and newly designed differential probes were placed depths 0.1, 0.2, 0.3, 0.4, 0.5, 0.75, 1, 1.5, m. procedure situ recalibration every 6 or 7 wk these probes. At same depths, capacitive thermocouples measured volumetric water content temperature, respectively. bulk density profile, table level, rainfall amounts recorded. atmospheric ranged between 97 000 101 Pa during experiment. signal drift negligible four 2000 Pa. These differences, which are necessarily linked depth, probably due heterogeneities generally infiltration. Air seemed level out quickly when air-filled pore space continuous. This prevented “dephasing-amortization” effects. When discontinuous, pressures depended simultaneously temperature fluctuations.