Permeable

Permeable [ Biology - Horticulture - Pedology ]
Synonym: Passable


	*Allowing substances, particularly gases and liquids, to penetrate or pass through , such as a soil with pores or openings through which water can flow.*

A permeable soil is able to be penetrated by water and air. Usually used in horticulture to indicate growing substrata and soils types (such as unconsolidated pumices grit and coarse sand) thought which water can easily seep (or rise). Water cannot, by definition, travel through impermeable layers.

Permeation [ Physics]

Dictionary of botanic terminology - index of names

The passage or diffusion of a gas, vapor, liquid, or solid through a barrier without physically or chemically affecting it.

The permeation is the process of permeating or infusing something with a substance or the interpenetration ( mutual penetration) of a substance through another.

To permeate [ Transitive and intransitive verb]


	*To penetrate and pass through, as water penetrates and passes through soil interstices and other porous materials.*

Permeability
Synonym: Pore connectivity


	Ability of a material or substance to transmit fluids through pore spaces

Advertising

Holdfast roots [ Botany ]
Dictionary of botanic terminology - index of names

Some species of climbing plants develop holdfast roots which help to support the vines on trees, walls, and rocks. By forcing their way into minute pores and crevices, they hold the plant firmly in place.

Climbing plants, like the poison ivy (Toxicodendron radicans), Boston ivy (Parthenocissus tricuspidata), and trumpet creeper (Campsis radicans), develop holdfast roots which help to support the vines on trees, walls, and rocks. By forcing their way into minute pores and crevices, they hold the plant firmly in place. Usually the Holdfast roots die at the end of the first season, but in some species they are perennial. In the tropics some of the large climbing plants have hold-fast roots by which they attach themselves, and long, cord-like roots that extend downward through the air and may lengthen and branch for several years until they strike the soil and become absorbent roots.

Major references and further lectures:
1) E. N. Transeau “General Botany” Discovery Publishing House, 1994