Subcategories


 

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Biological control

The use of biological agents (intact organisms, components derived from organisms) to destroy or deter pests or to promote natural enemies.

Biological soil crust

Also called microbiotic, microphytic, cryptobiotic or cryptogamic crusts. A living community of bacteria, microfungi, cyanobacteria, green algae, mosses, liverworts, and lichens that grow on or just below the soil surface. Biological crusts can heavily influence the morphology of the soil surface, stabilize soil, fix carbon and nitrogen, and can either increase or decrease infiltration. The percent cover and the components of the crust can vary across short distances. Identification of biological crust organisms is simplified through the use of three broad morphological groups: The cyanobacteria group includes cyanobacteria and green algae. The moss group includes short and tall mosses, but not club moss mats, such as those in northern latitudes, or spike moss. The lichen group includes crustose, gelatinous, squamulose, foliose, and fruiticose lichen, as well as liverworts.

Biomass

As simple as 'above and below-ground vegetative material'; or more complex to include microbial contributions or specific uses, such as for fuel.

Biota

A soil formation factor that describes living organisms in a particular region and at a particular time. It includes vegetation, microbes, soil animals, and human beings.

Black Earth

Term synonymous with Chernozem used (e.g. in Australia) to describe self-mulching black clays.

Bog

Wetland that has no significant inflows or outflows, supports acidophilic mosses, particularly Sphagnum and in which peat is accumulating. Similar to: fen, marsh, pocosin, swamp, and wetland.

Boulder clay

Unstratified glacial deposits laid down directly beneath the ice or dropped from the surface as the ice melted; boulder clay and till are synonymous terms for this unsorted material which ranges from rock flour to rocks and boulders of great size, according to the nature of the bedrock.

Buffering of fields

The presence of terraces, treelines, buffer zones, riparian zones, which all contribute to intercepting overland flow.

Bulk density

The dry mass of soil per unit bulk volume of soil, expressed as g/cm3, usually given on an oven-dry (110

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