- 行业: Earth science
- Number of terms: 26251
- Number of blossaries: 0
- Company Profile:
An international scientific society that fosters the transfer of knowledge and practices to sustain global soils. Based in Madison, WI, and founded in 1936, SSSA is the professional home for 6,000+ members dedicated to advancing the field of soil science. It provides information about soils in ...
Vertisols of temperate or tropical regions that have wide, deep cracks that usually remain open for periods that total >90 days but do not remain open continuously throughout the year, and have either a mean annual soil temperature of 22°C or more or a mean summer and mean winter soil temperature at 50 cm below the surface that differ by <5°C or have cracks that open and close more than once during the year.
Industry:Earth science
The relative solute concentration in the outflow from a column of soil or porous medium after a step change in solute concentration has been applied to the inlet end of the column, plotted against the volume of outflow (often in number of pore volumes).
Industry:Earth science
The calculated pH that a solution would have if it were in equilibrium with calcium carbonate. Numerically, pHc* is equal to (pK2 - pKc) + p(Ca) + pAlk, where p(Ca) and pAlk are the negative logarithms of the molar concentrations of Ca and of the equivalent concentration of (CO3 + HCO3), respectively, and pK2 and pKc are the negative logarithms of the second dissociation constant of H2CO3 and the solubility constant of CaCO3, respectively, both corrected for ionic strength. It is used in conjunction with the measured pH of a water to determine if CaCO3 will precipitate from the water, or if the water will dissolve CaCO3 as it passes through a calcareous soil.
Industry:Earth science
The ratio of cation valence to coordination number (z/n)
Industry:Earth science
The soil is saturated with water in one or more layers within 200 cm of the mineral soil surface and also has one or more unsaturated layers with an upper boundary above 200 cm depth, below the saturated layer(s) (a perched water table).
Industry:Earth science
The relative proportions of primary nutrients in a fertilizer grade divided by the highest common denominator for that grade, e.g., grades 10-6-4 and 20-12-8 have a ratio 5-3-2.
Industry:Earth science
The mass of dry soil per unit bulk volume. The value is expressed as Mg per cubic meter, Mg m-3.
Industry:Earth science
Water that seeps toward stream channels after infiltration into the ground.
Industry:Earth science
The sequence of transformations undergone by sulfur wherein it is used by living organisms, transformed upon death and decomposition of the organism, and ultimately converted to its original oxidation state.
Industry:Earth science
Topography with sinkholes, caves, and underground drainage that is formed in limestone, gypsum, or other rocks by dissolution.
Industry:Earth science
