Organic residues, or a mixture of organic residues and soil, that have been piled, wetted, and allowed to undergo biological decomposition. Mineral fertilizers are sometimes added.
The protection or improvement and use of natural resources according to principles that will assure their highest economic or social benefit, for some specified purpose.
A close growing crop grown primarily for the purpose of protecting and improving soil between periods of regular crop production, or in orchards and vineyards.
A planned sequence of crops growing in a regularly recurring succession on the same area of land, as contrasted to continuous culture of one crop growing different crops in haphazard order.
A surface layer on soils, ranging in thickness from a few millimetres to as much as 3 cm, that physical-chemical processes have caused to be much more compact, hard and brittle when dry than the material immediately beneath it.