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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 ...
A percolation test consists of digging one or more holes in the soil of the proposed leach field to a specified depth, presoaking the holes by maintaining a high water level in the holes, then running the test by filling the holes to a specific level and timing the drop of the water level as the water percolates into the surrounding soil.
Soil gradation is determined by analyzing the results of a sieve analysis or a hydrometer analysis. [4] [5] In a sieve analysis, a coarse-grained soil sample is shaken through a series of woven-wire square-mesh sieves. Each sieve has successively smaller openings so particles larger than the size of each sieve are retained on the sieve.
The Universal Soil Loss Equation (USLE) is a widely used mathematical model that describes soil erosion processes. [1]Erosion models play critical roles in soil and water resource conservation and nonpoint source pollution assessments, including: sediment load assessment and inventory, conservation planning and design for sediment control, and for the advancement of scientific understanding.
Waterlogged wood is a wooden object that has been submerged or partially submerged in water and has affected the original intended purpose or look of the object. Waterlogged wood objects can also include wood found within moist soil from archaeological sites, underwater archaeology, maritime debris, or damaged wood objects.
Symbol used in drawings Standard penetration test N values from a surficial aquifer in south Florida.. The standard penetration test (SPT) is an in-situ dynamic penetration test designed to provide information on the geotechnical engineering properties of soil.
The major archaeological problem with waterlogged finds, particularly wood, is that they deteriorate rapidly when they are uncovered, beginning to dry and crack almost at once. They therefore need to be kept wet until treated in a laboratory. Conservation measures explain why wet archaeology costs around four times as much as dry archaeology.
Consequently, acid sulfate soil samples should be immediately cooled to < 4°C to slow oxidation; and samples containing monosulfidic material should be immediately frozen (e.g., using a portable freezer or liquid nitrogen). [31] The use of dry ice is recommended as the gaseous carbon dioxide should further hinder oxidation.