Redox Potential in Irrigated Desert Soils as an Indicator of Aeration Status

Abstract

The redox potential (Eh) of irrigated desert soils was evaluated under a wide range of conditions. Factors important in controlling Eh were temperature, flooding time, soil water content, and energy source. Field heterogeneity necessitated using 10 to 20 electrodes (placed in a 30‐cm square) to characterize a treatment. The Eh varied over a short distance with variations not due to poisoning or erratic electrode readings.A 5C increase in temperature at the 15‐cm depth resulted in a 50‐mV decrease in redox potential. The length of soil saturation time correlated directly with the decrease in Eh. When the soil was not saturated during irrigation (sprinkler or drip), Eh decreased less than when the soil was flooded. The amount of energy available to microorganisms has a major effect on how low the Eh decreased in a flooded soil.

Variação temporal e vertical de atributos químicos de um gleissolo do Rio Guamá cultivado com Canaranas

“…Nesse sentido, Meek & Grass (1975) A concentração de N foi significativamente menor no período de maior inundação (fevereiro), em todas as profundidades de amostragens e nas duas áreas estudadas (Quadro 2). Em solos ácidos e anaeróbios com pH menor que 5,5, a taxa de nitrificação é muito baixa, o que resulta em acumulação de amônia (NH 3 ), que pode ser perdida por volatilização, ou amônio (NH 4 + ), devido à pequena disponibilidade de O 2 necessário à conversão microbiana da amônia em nitrato .…”

Laboratory Column Evaluation of High Explosives Attenuation in Grenade Range Soils

“…The O 2 consumption rates are a function of both the quantity and quality of OC (Yiqi and Zhou, 2010). Incorporation of organic material can substantially increase soil respiration and O 2 demand (Meek and Grass, 1975; Flessa and Beese, 1995). In batch microcosms using grenade range soil from Fort Bragg, NC, TNT was rapidly biodegraded under both aerobic and anaerobic conditions (Won and Borden, 2016).…”

The redox potential: Its use and control in biotechnology

“…The level of the redox potential depends on several factors in the soil. Meek and Grass (1975) investigated the effect of different factors on the redox potential in irrigated desert soils and found that a decrease in redox potential occurred as a result of (1) an increase in temperature (in the range 0-20 °C), (2) prolongation of the soil saturation time, and (3) higher amounts of substrate added to the soil. These findings all indicate that the changes in redox potential are due to microbial activity.…”