ABSTRACT Methane (CH4) is the second major greenhouse gas after CO2, exerting a significant influence on the climate and the chemistry of the atmosphere. In lowland soil, acetate and H2/CO2 are the most important precursors of CH4 and formed from organic matter fermentation in an anaerobic environment, giving rise to short-chain organic acids (ethanoic, propanoic, and butanoic), depending on the type of crop residue and the soil management system. Ethanoic acid can be directly converted to CH4 by methanogenic microorganisms, […]

Ammonia volatilization and nitrification/denitrification are the two major N loss mechanisms in rice production. If N fertilizer is not managed appropriately, N recovery by rice plants can be low. The purpose of this study was to quantify ammonia volatilization in flooded soils influenced by the urea application method. A greenhouse study was conducted to quantify the potential of N loss via ammonia volatilization in flooded soils influenced by the urea application method. Two experiments were carried out, one in Mississippi, […]

The sustainability of irrigated rice (Oryza sativa L.) in lowland soils is based on the use of crop rotation and succession, which are essential for the control of red and black rice. The effects on the soil properties deserve studies, particularly on soil compaction. The objective of this study was to identify compacted layers in an Albaqualf under different cultivation and tillage systems, by evaluating the soil bulk density (Ds) with Gamma Ray Computed Tomography (TC). The analysis was carried […]

Differences in grain yield were not observed in experiments with paddy rice when comparing soluble phosphates and rock phosphate as phosphorus sources. However, chemical changes in flooded soils such as increases in pH and phosphorus and calcium levels in the soil solution probably decrease the dissolution of rock phosphates in flooded soils. The current work was therefore carried out with the objective of studying the solubilization of phosphate rocks in flooded soils. Two experiments, conducted in a random block design […]