soil- +

1. A fine-grained fertile soil deposited by water flowing over flood plains or in river beds.
2. Fertile soil that can be found in aquatic communities (living in or on water for all or a substantial part of the life span; generally restricted to fresh water or inland waters).

1. A type of soil that develops in arid, or dry, climates.
2. A soil that develops under sparse shrub vegetation in warm to cool arid climates with a light-colored surface soil usually underlain by calcareous material and a hardpan layer.
3. A soil variety typically found in arid climates, usually with little leaching and minimal humus content.

Referred to as an "aridisol" in the nomenclature of the United States Department of Agriculture's Natural Resources Conservation Service.

Any soil consisting primarily of minerals; such as, sand, silt and clay materials; rather than organic matter (composting and mulching).

Human excrement collected at night from non-flushable toilets or cesspools; especially, for use as fertilizer.

The well drained soils of an association which have developed under the dominant influence of the natural vegetation characteristic of a region.

The zonal soils of an area.

Soil formed on a pre-existing landscape but which was not subsequently buried under younger sediments.

It should be taken into account that relict soils may represent a wide range of time periods.

A soil unusable for agricultural purposes because it contains more than 15% exchangeable sodium, has a high content of soluble salts, and a pH of less that 9.5.

1. The portion of the earth's surface consisting of disintegrated rock and humus: "Some plants cannot develop in poorly drained soils."
2. All loose, unconsolidated, weathered, or otherwise altered surface material lying on the earth above bedrock. 3. A particular kind of earth; such as, sandy soil.
4. The ground when producing vegetation or as cultivated for its crops: "We used fertile soil for our garden."
5. The biologically active, porous medium that has developed in the uppermost layer of the earth's crust. 6. A country, land, or region: "The criminal act was committed on American soil."
7. The ground or earth: "The farmers were tilling their soil."
8. Any place or condition providing the opportunity for growth or development: "Some people believe that poverty provides the soil for crime and social instability."

In agronomy, the process of adding substances to the soil to improve plant growth.

A mapping unit used in detailed soil surveys consisting of two or more distinguishable soils in a given geographic area which are grouped together on the basis of their areal (area) distribution.

The air occupying the pore or open spaces in soil.

Carbon contained in the solid surface layer of the earth.

The amount of carbon in the soil is a function of the historic vegetative cover and productivity, which in turn is influenced by climatic variables.

Any of various methods of land management that seek to protect the soil from erosion and chemical decay, so as to maintain its quality.

The technique of strip cropping (alternating different crops) is one method of soil conservation because it is believed to provide almost total resistance to erosion.

The study of the relationship between the activities of soil organisms and the overall soil environment.

The detachment and transportation of topsoil by the action of wind and running water.