Saturated / unsaturated zone

Saturated / unsaturated zone

Saturated zone - is a system with two phases (solid and liquid) where all pores are filled with water.

Unsaturated zone - is a system with three phases (solid, liquid and gas) where only a part of the ground is filled with water.

 

The fundamental difference between saturated and unsaturated zones consists in different hydraulic conductivities.

It can be distinguished:

·         water from soil representing water from the unsaturated zone, and which is the transit bond between matter and substances. These processes are part of a continuous cycle soil-plants-atmosphere.

·         subsurface water level is influenced by rain percolation regime or irrigation water that crosses through the unsaturated zone.

Two cases are distinguished:

1.     in case of an unsaturated environment, hydraulic conductivity varies with soil humidity and water effective pressure, which is negative.
2.      in case of a saturated environment, effective water pressure in soil is positive and depends on the depth of submersion below the free water surface.

Aquifer

An aquifer is a wet underground layer of water-bearing permeable rock or unconsolidated materials (gravel, sand, or silt) from which groundwater can be usefully extracted using a water well.

Contaminate Groundwater

 Contaminate Groundwater:

Groundwater not only contains the hydrogen and oxygen atoms that form water (H₂O), but it also contains naturally dissolved gases from the atmosphere and dissolved minerals and gases from the soil and rock through which it passes.
The soil filters the water and absorbs and removes many contaminants though some will pass through unimpeded.  But if the soil layer is thin, has high permeability, or if the water table is close to the land surface, then the soil is less likely to adequately treat contamination.  The excess contaminants may pass through the zone of aeration and enter the groundwater in the zone of saturation. 

Hydrology cycle of water

Definition of Hydrology:

Water is vital for all living organisms on Earth. For centuries, people have been investigating where water comes from and where it goes, why some of it is salty and some is fresh, why sometimes there is not enough and sometimes too much. All questions and answers related to water have been grouped together into a discipline. The name of the discipline is hydrology and is formed by two Greek words: "hydro" and "logos" meaning "water" and "science". Hydrology is the science concerned with the occurrence, distribution, movement and properties of all the waters of the Earth.

The total amount of water on Earth is invariable. At the same time water is continuously renewed while circulating between oceans, land and atmosphere. All processes like evaporation, condensation, precipitation, interception, transpiration, infiltration, storage, runoff, and groundwater flow which keep water in motion constitute the hydrologic cycle. Those processes are stimulated by solar energy. They take place simultaneously and, except for precipitation, continuously. Consider Figure:

 

o       evaporation, (release of water vapour/steam by a free surface at a temperature below the boiling point. Through evaporation water leaves the land and oceans, rising into atmosphere.)

o       condensation, (The change in water phase, from a vapour state into a liquid state. The condensation is produced by way of air cooling below the dew point and by the deposition of the water vapours on the nucleus of condensation.)

o       precipitation, (Liquid or solid products of the condensation of water vapour falling from clouds or deposited from the air on the ground. For example, rain, sleet, snow, hail.)

o       interception, (The process by which precipitation is caught and held by vegetation (canopy and litter structures) then may be lost by evaporation without reaching the ground.) 

transpiration, (The process by which water from vegetation is transferred into the atmosphere in the form of vapour.) 

 

o     infiltration, (The process of entry of water into a soil through the soil surface.      The part of rainfall that enters the soil)

o       storage, (Volume of water stored.)

o       runoff, (The part of precipitation that flows towards the stream on the ground surface (surface runoff) or within the soil (subsurface runoff). That part of the precipitation appearing in surface streams. The portion of precipitation that, after reaching the ground surface, runs off to a water body.)

o       groundwater flow, (Movement of water in an aquifer. It is considerably slower than surface runoff. Groundwater flows until reaches lakes, rivers or oceans. It can also reach the surface through artesian wells.)

 

Porous

Porous:

• Compost requires oxygen to decompose, so you need some kind of open, porous  container.
•  Having minute holes through which liquid or air may pass.
• able to absorb fluids; "the partly porous walls of our digestive system"; "compacting the soil to make it less porous"
• adjective permeable, absorbent, spongy, absorptive, penetrable,  The local limestone is extremely porous 

With the making of an entirely new porous aluminum, Sumitomo Electric Industries Ltd has enhanced the capacity of lithium-ion (Li-ion) rechargeable batteries and capacitors. This certainly appears good news for manufacturers and dealers of products which use Li-ion rechargeable batteries. Sumitomo Electric Industries Ltd is a leading Japanese producer of items like cables, semiconductor equipments and the other alike things. The invention, which is a new porous aluminum, has been named as “Aluminum-Celmet”.

Permeable : Capable of being passed through or permeated, especially by liquids or gas. Allowing fluids or gases to pass or diffuse through; "permeable membranes"; "rock that is permeable by water"

Permeable Paving

Traditional urban construction has diverted rainwater into storm sewers and ultimately into streams, rivers and lakes. This diversion of rainwater has resulted in over-taxed sewer systems, as well as chemically and thermally polluted waters.

Benefits of Permeable Paving

• Reduces storm water load
• Eliminates thermal pollution of stream & rivers
• Naturally filters contaminants & replenishes the water table
• Enables rainwater to to be easily harvested
• Promotes healthy ecology

Impact on Trees

Porous pavements give urban trees the rooting space they need to grow to full size. A "structural-soil" pavement base combines structural aggregate with soil; a porous surface admits vital air and water to the rooting zone. This integrates healthy ecology and thriving cities, with the living tree canopy above, the city's traffic on the ground, and living tree roots below.

Absorbent :A substance that is capable of absorbing. a material having capacity or tendency to absorb another substance 

It can increase the survival rate of plants and vegetation by retenting water as the absorbent polymer in agriculture or garden

"Jinyue"SAP is a new type macro molecular material, which can absorb water of hundreds or even thousands times of its weight. It’s nontoxic, harmless and nonpolluting with super water absorbing ability and water preserving ability while absorbing water cannot be squeezed out in simply physical ways, and it can release and absorb water repeatedly. Used in agriculture and forestry, it can form a micro reservoir at plants’ root. Super Water-Absorbent polymer absorbs not only water, but also fertilizer, pesticide .It will release them gradually to enhance effect of fertilizer and pesticide. Super Water-Absorbent polymer is widely used in agriculture and forestry industry, municipal gardening, drought resisting and water preserving, and sand resisting and controlling aspects, and is playing an important role. Additionally, Super Water-Absorbent Colophony can also be used in medical, oil exploitation, construction material, transportation and many other fields.

 

Absorber(Noun) - (physics) material in a nuclear reactor that absorbs radiation

Absorbent(Adj.) - having power or capacity or tendency to absorb or soak up something (liquids or energy etc.); "as absorbent as a sponge"

Spongy - Easily squashed; resembling a sponge in having soft porous texture and compressibility; "spongy bread". Llike a sponge in being able to absorb liquids and yield it back when compressed

Absorptive - having power or capacity or tendency to absorb or soak up something (liquids or energy etc.); "as absorbent as a sponge"

Penetrable - admitting of penetration or passage into or through; "a penetrable wall"; "penetrable defenses"

Imbibing - ( To drink.)The act of consuming liquids   

Limestone

Limestone rocks are sedimentary rocks that are made from the mineral calcite which came from the beds of evaporated seas and lakes and from sea animal shells. This rock is used in concrete and is an excellent building stone for humid regions.  

A wide collection of limestone cobbles that are extensively used for pavements, pathways, and all other types of exterior application. Fire proof in nature, these cobbles does not require any maintenance. Available in different sizes, these cobbles are offered at industry. 

Usage :

• Steel industries and blast furnaces.
• Glass Industries
• Poultry sector for feed manufacturing and direct feeding.
• Cement Industries
• Construction
• Soil conditioning etc.