Electrical Conductivity (EC) reading shows the level of ability the soil water has to carry an electrical current.
Testing the EC of your soils. The way that Electrical conductivity can be measured is using an EC meter. The probe or sensor consists of two metal electrodes and a constant voltage is applied across the electrodes resulting in an electrical current flowing through the sample. Since the current flowing through the water is proportional to the concentration of dissolved ions in the water, the electrical conductivity can be measured. The higher the dissolved salt/ion concentration, the more conductive the sample and hence the higher the conductivity reading. Lower pH corresponds with higher [H + ], while higher pH is associated with lower [H + ]. Electrical conductivity (EC) is a measurement of the dissolved material in an aqueous solution, which relates to the ability of the material to conduct electrical current through it. pH is a measure of the acidity of the water or soil based on its hydrogen ion concentration and is mathematically defined as the negative logarithm of the hydrogen ion concentration, or. pH = -log[H + ], where the brackets around the H + symbolize concentration. It is often useful to characterize an environment,such as a body of water, by measuring its pH and electrical conductivity (EC). pH is a measure of the acidity of the water or soil based on its hydrogen ion concentration and is mathematically defined as the negative logarithm of the hydrogen ion concentration, or. pH = -log[H + ], where the brackets around the H + symbolize concentration. Electrical Conductivity Information Sheet BACKGROUND Conductivity is one way to measure of the inorganic materials including calcium, bicarbonate, nitrogen, phosphorus, iron, sulphur and other ions dissolved in a water body.  Electrical resistivity (also known as resistivity, specific electrical resistance, or volume resistivity) is an intrinsic property that quantifies how strongly a given material opposes the flow of electric current. A low resistivity indicates a material that readily allows the movement of electric charge. The electrical resistivity of a metallic conductor decreases gradually as temperature is lowered. In ordinary conductors, such as copper or silver, this decrease is limited by impurities and other defects. Even near absolute zero, a real sample of a normal conductor shows some resistance. Electrical Resistivity. Electrical resistivity is the reciprocal of conductivity. It is the is the opposition of a body or substance to the flow of electrical current through it, resulting in a change of electrical energy into heat, light, or other forms of energy. The amount of resistance depends on the type of material.  Electrical Resistance. Another way of describing the conductivity of a material is through resistance. Resistance can be defined as the extent to which a material prevents the flow of electricity. Silver, aluminum, iron and other metals have a low resistance (and a high conductivity). TDS and Electrical Conductivity. Since the electrical conductivity is a measure to the capacity of water to conduct electrical current, it is directly related to the concentration of salts dissolved in water, and therefore to the Total Dissolved Solids (TDS).  Electrical conductivity is the ability of a material to carry the flow of an electric current (a flow of electrons). Imagine that you attach the two ends of a battery to a bar of iron and a galvanometer. Another way of describing the conductivity of a material is through resistance. Resistance can be defined as the extent to which a material prevents the flow of electricity. Silver, aluminum, iron and other metals have a low resistance (and a high conductivity). In the soil, the Electrical Conductivity (EC) reading shows the level of ability the soil water has to carry an electrical current. Since the current flowing through the water is proportional to the concentration of dissolved ions in the water, the electrical conductivity can be measured. The higher the dissolved salt/ion concentration, the more conductive the sample and hence the higher the conductivity reading.
http://www.agriculturesolutions.com/resources/92-the-why-and-how-to-testing-the-electrical-conductivity-of-soils http://serc.carleton.edu/microbelife/research_methods/environ_sampling/pH_EC.html http://serc.carleton.edu/microbelife/research_methods/environ_sampling/pH_EC.html http://www.gbwaterwatch.org.au/resources/ID1297390048.pdf https://en.wikipedia.org/wiki/Electrical_conductivity https://www.nde-ed.org/EducationResources/CommunityCollege/Materials/Physical_Chemical/Electrical.htm http://www.scienceclarified.com/Di-El/Electrical-Conductivity.html http://www.smart-fertilizer.com/articles/electrical-conductivity http://www.scienceclarified.com/Di-El/Electrical-Conductivity.html http://www.agriculturesolutions.com/resources/92-the-why-and-how-to-testing-the-electrical-conductivity-of-soils
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