Degrees of acidity of pH.
pH of the water shows the activity of hydrogen ion in the solution and expressed as a hydrogen ion concentration (in mol per liter) on a certain temperature, or can be written:
pH = log (H) * Pure water (H2O) was imperfect, so have the ion H and OH-ion in the same concentration, and in this mummy water pH = 7. The higher the concentration of H ion will be more low-OH-ion concentration and pH <7,> 7, the waters are basa (alkalis). Public waters, including sea water with all the activities of photosynthesis and respiration of living organisms in forming a chain reaction Carbonate-Carbonate as follows:
CO2 H2O -> H2CO3 -> H HCO3 -> 2h-CO32 -
The more CO2 generated from the results of respiration, the reaction moving to the right and gradually release the ion H pH of the water that cause the decrease. Reaction happens with activity as photosynthesis, which requires a lot of ion CO 2, causing the pH of the water board.
Sea water, with a content-ions Ca and Mg, which is large enough, can prevent large fluctuations of pH.
Ions Calsium and Magnesium will form carbonic salt-and salt mixture of bicarbonate and acid-carbonic acid with the salt-salt establish a system of buffer (buffer) is strong. Hence, the pH of sea water usually are slightly above normal and rarely out of bounds pH 7 - 9. The situation is very beneficial animals in it, including shrimp, because the activity respirasinya produce CO2 cause the pH around the gills slightly down, so should immediately return dinetralkan. The optimum pH value for the life of shrimp are in the range of 7 to 8.5. Nevertheless often happens capacity buffer sea water not be able to decrease the pH of the soil affected by the depth of basic embankment. Many cases this happens, especially in the ponds, ponds built in the area of land that contains pyrite (FeS2).
Pyrite is the closest to the air will oxidise hydrogen ion with the result that quite a lot, so that they can lower the pH of the water to below the value of 4. Increasing the value of the pH to a level that endanger the very rare in the ponds. Even if it occurs, can be overcome by fertilizing the acid reacts, such as sulfur fertilizer, sulphate fertilizers combined with organic fertilizer. If there is the tendency of increasing the pH, should do the replacement of some of the volume of water ponds. Case decrease the pH more often found in ponds, especially the new embankment. There are two ways to overcome the low pH value of soil acidity caused this basis, namely with
management and with the reclamation action.
source: Ir. Sri Umiyati Sumeru
Dra. Suzy Anna
