Nitric Oxide and Nitrous Oxide Production from Soil: Water and Oxygen Effects
1992
Drury, C. F. | Findlay, W. I. | McKenney, D. J.
This study was designed to determine the effects of water and O₂ on the speciation of denitrification gases (NO and N₂O). Nitric oxide was found to be the principal end product from soil incubated under low-moisture conditions, whereas the relative amount of N₂O increased under wetter moisture regimes. The total amount of NO plus N₂O produced increased with increasing water content for the Brookston clay loam (fine-loamy, mixed, mesic Typic Argiaguoll), whereas it peaked at 150 g kg⁻¹ (15%) water content with the Fox sandy loam (fine-loamy over sandy or sandy or sandy-skeletal, mixed, mesic, Typic Hapludalf). The decrease in NO plus N₂O at higher water contents was probably the result of the subsequent reduction of N₂O to N₂ in the Fox sandy loam soil. The residence time of the denitrification gases in the soil increased with increasing water content, hence facilitating the subsequent conversions of NO to N₂O and N₂. The thickness of the water film surrounding the microbes affected both the diffusion of O₂ through the water and into the microbes as well as the diffusion of denitrification gases (NO, N₂O, and N₂) from the microbes into the atmosphere. In the sandy loam soil, O₂ content and soil water affected both the amount and species of evolved denitrification gases. Oxygen was more effective in decreasing NO production at lower than at higher water contents.
Показать больше [+] Меньше [-]Ключевые слова АГРОВОК
Библиографическая информация
Эту запись предоставил National Agricultural Library