- 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 ...
A nonunique relationship between two variables, wherein the curves depend on the sequences or starting point used to observe the variables. Examples include the relationships: (i) between soil-water content and soil-water matric potential, (ii) between solution concentration and adsorbed quantity of chemical species, and (iii) between soil volume and water content for swelling and shrinking soils.
Industry:Earth science
A great soil group of the intrazonal order and hydromorphic suborder. Includes muck and peat.
Industry:Earth science
A soil temperature regime that has mean annual soil temperatures of 8°C or more but <15°C, and >5°C difference between mean summer and mean winter soil temperatures at 50 cm below the surface. Isomesic is the same except the summer and winter temperatures differ by <5°C.
Industry:Earth science
A coarse-textured soil; a soil with a low drawbar pull and hence easy to cultivate.
Industry:Earth science
A soil temperature regime that has mean annual soil temperatures of >0°C but <8°C, >5°C difference between mean summer and mean winter soil temperatures at 50 cm below the surface, and warm summer temperatures. Isofrigid is the same except the summer and winter temperatures differ by <5°C.
Industry:Earth science
A soil containing sufficient exchangeable sodium to interfere with the growth of most crop plants and containing appreciable quantities of soluble salts. The exchangeable sodium ratio is greater than 0. 15, conductivity of the soil solution, at saturated water content, of >4dS m-1(at 25 °C), and the pH is usually 8. 5 or less in the saturated soil.
Industry:Earth science
Relatively insoluble phosphorus compounds resulting from reactions of phosphorus with soil constituents: e. g. calcium and magnesium phosphates which are precipitated above a pH of about 6. 0 to 6. 5 (if calcium and magnesium are present); and, iron and aluminum phosphates which are precipitated below a pH of about 5. 8 to 6. 1.
Industry:Earth science
A classification of earth materials with equivalent particle diameters less than 2. 0 mm based solely on particle-size distribution.
Industry:Earth science
A mass of interwoven filamentous hyphae, such as that of the vegetative portion of the thallus of a fungus.
Industry:Earth science
A strategy of growing adapted crops with cropping and fallow decisions at each prospective date of planting based on available water in the soil plus expected growing season precipitation and without regard to a predetermined rigidly adhered to cropping sequence.
Industry:Earth science
