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Groundwater recharge or deep drainage is a hydrologic process where water moves downward from surface water to groundwater. Hydrology (from Greek Yδωρ hudōr, "water" and λόγος logos, "study" is the study of the movement distribution and quality of Water is a common Chemical substance that is essential for the survival of all known forms of Life. For Water masses on the surface of the world ocean see Surface water (ocean. Groundwater is Water located beneath the Ground surface in Soil pore spaces and in the Fractures of lithologic formations This process usually occurs in the vadose zone below plant roots, and is often expressed as a flux to the water table surface. The vadose zone, also termed the unsaturated zone, is the portion of Earth between the land surface and the phreatic zone or zone of saturation ("vadose" ROOT is an object-oriented program and library developed by CERN. In the various subfields of Physics, there exist two common usages of the term flux, both with rigorous mathematical frameworks The water table is the level at which the ground water pressure is equal to Atmospheric pressure. Recharge occurs both naturally (through the water cycle) and anthropologically (i. The Earth 's Water is always in movement and the water cycle, also known as the hydrologic cycle, describes the continuous movement of water on above e. , "artificial groundwater recharge"), where rainwater and or reclaimed water is routed to the subsurface. Reclaimed water, sometimes called recycled water, is former Wastewater (sewage that has been treated to remove solids and certain impurities and then allowed

Groundwater is recharged naturally by rain and snow melt, though this may be impeded somewhat by human activities including paving ground or cutting down forests. Groundwater is Water located beneath the Ground surface in Soil pore spaces and in the Fractures of lithologic formations These activities can result in enhanced surface runoff and reduction in recharge. Surface runoff is a term used to describe when soil is infiltrated to full capacity and excess Water, from Rain, Snowmelt, or other sources flows Use of groundwater, especially for farming, may also lower the water tables. Groundwater recharge is an important process for sustainable groundwater management, since the volume-rate abstracted from an aquifer should be less than or equal to the volume-rate that is recharged. Sustainability, in a general sense is the capacity to maintain a certain process or state indefinitely Water abstraction, or water extraction, is the process of taking Water from any source either temporarily or permanently An aquifer is an underground layer of Water -bearing Permeable rock or unconsolidated materials ( Gravel, Sand, Silt, or Clay

Recharge can help move excess salts that accumulate in the root zone to deeper soil layers, or into the ground water system. This is evident through the salinity of the upper soil layers, where at least 25,000 km² of Australia and 5% of current cultivated land has elevated salinities. Salinity is the Saltiness or dissolved salt content of a body of Water. Another environmental issue is the disposal of waste through the water flux such as dairy farms, industrial, and urban runoff. Surface runoff is a term used to describe when soil is infiltrated to full capacity and excess Water, from Rain, Snowmelt, or other sources flows

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Estimation methods

Rates of groundwater recharge are difficult to quantify, since other related processes, such as evaporation, transpiration (or evapotranspiration) and infiltration processes must first be measured or estimated to determine the balance. Evaporation is the process by which Molecules in a Liquid state (e Transpiration is the Evaporation of water from the aerial parts of Plants especially leaves but also stems Flowers and Roots Evapotranspiration (ET is a term used to describe the sum of Evaporation and Plant Transpiration from the earth's land surface to Atmosphere

Physical

Physical methods use the principles of soil physics to estimate recharge. Soil physics is the study of soil physical properties and processes The direct physical methods are those that attempt to actually measure the volume of water passing below the root zone. Indirect physical methods rely on the measurement or estimation of soil physical parameters, which along with soil physical principles, can be used to estimate the potential or actual recharge.

Chemical

Chemical methods utilize the presence of water-soluble substances, such as an isotopic tracer, moving through the soil, as deep drainage occurs. Isotopic labeling is a technique for tracking the passage of a sample of substance through a system

Numerical models

Recharge can be estimated using numerical methods, using such codes as HELP, UNSAT-H, SHAW, and MIKE SHE. Numerical analysis is the study of Algorithms for the problems of continuous mathematics (as distinguished from Discrete mathematics) In Computer science, source code (commonly just source or code) is any sequence of statements or declarations written in some Human-readable The HELP model (Hydrologic Evaluation of Landfill Performance is a hydrologic numerical model initially developed by the United States Environmental Protection MIKE SHE is an integrated Hydrological modelling system for building and simulating Surface water flow and Groundwater The 1D-program HYDRUS1D is available online. These codes generally use climate and soil data to arrive at a recharge estimate, and use Richards equation in some form to model groundwater flow in the vadose zone. Climate encompasses the temperatures humidity rainfall atmospheric particle count and numerous other meteorogical factors in a given region over long periods of Soil, often typeset as SOiL, is a four piece rock band from Chicago Illinois United States founded by Shaun Glass Tom Schofield Tim King and Adam Zadel The Richards equation represents the movement of water in Unsaturated soils and was formulated by Lorenzo A The vadose zone, also termed the unsaturated zone, is the portion of Earth between the land surface and the phreatic zone or zone of saturation ("vadose"

See also

References

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