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A hydric soil is defined by federal law [4] to mean "soil that, in its undrained condition, is saturated, flooded, or ponded long enough during a growing season to develop an anaerobic condition that supports the growth and regeneration of hydrophytic vegetation".
Soil may be regarded as waterlogged when it is nearly saturated with water much of the time such that its air phase is restricted and anaerobic conditions prevail. In extreme cases of prolonged waterlogging, anaerobiosis occurs, the roots of mesophytes suffer, and the subsurface reducing atmosphere leads to such processes as denitrification ...
Nitrogen fertilizer being applied to growing corn in a contoured, no-tilled field in Iowa.. Nutrient management is the science and practice directed to link soil, crop, weather, and hydrologic factors with cultural, irrigation, and soil and water conservation practices to achieve optimal nutrient use efficiency, crop yields, crop quality, and economic returns, while reducing off-site transport ...
The rows formed slow surface water run-off during rainstorms to prevent soil erosion and allow the water time to infiltrate into the soil. Soil conservation is the prevention of loss of the topmost layer of the soil from erosion or prevention of reduced fertility caused by over usage, acidification, salinization or other chemical soil contamination
Tilling the soil, or tillage, is the breaking of soil, such as with a plough or harrow, to prepare the soil for new seeds. Tillage systems vary in intensity and disturbance. Conventional tillage is the most intense tillage system and disturbs the deepest level of soils. At least 30% of plant residue remains on the soil surface in conservation ...
Obligate anaerobes are found in oxygen-free environments such as the intestinal tracts of animals, the deep ocean, still waters, landfills, in deep sediments of soil. [9] Examples of obligately anaerobic bacterial genera include Actinomyces , Bacteroides , Clostridium , Fusobacterium , Peptostreptococcus , Porphyromonas , Prevotella ...
Fully water-saturated wetland soils allow anaerobic conditions to manifest, storing carbon but releasing methane. [49] Wetlands make up about 5-8% of Earth's terrestrial land surface but contain about 20-30% of the planet's 2500 Gt soil carbon stores. [50] Peatlands contain the highest amounts of soil organic carbon of all wetland types. [51]
In soil, methane is produced in anaerobic environments by methanogens, but is mostly consumed in aerobic zones by methanotrophs. Methane emissions result when the balance favors methanogens. Wetland soils are the main natural source of methane.