(2006) found that relatively higher SAR values after second crop could be elaborated on the basis of more accumulation of salts which caused precipitation of CaSO4
and CaCO3 due to low solubility resulting into high Na+concentration and thus SAR.
En el caso Caso4
se realizan algunos eventos de capacitacion (entre ellos de la tematica TIC).
Weathering by dissolving action is important in areas with gypsum (CaSO4
Obtained solution can be more easily filtered than solution containing clay and CaSO4
Ganguly, "Thermoluminescence of CaSO4
doped with rare earths," Journal of Physics C: Solid State Physics, vol 7, no.
The mixing proportion was 1: 0.6: 2.5 (1 litre broth: 600g CaSo4
: 2.5kg charcoal), and was used in the field study as soil application at the rate of 10 kg [ha.sup.-1].
But pyretic sulfur and sulfur from gypsum can during combustion form anhydrite (CaSO4
) with CaO from calcite, while Fe from pyrite forms with oxygen hematite.
The obtained results indicate a light sub-saturation with regard to the halite (NaCl), and a sub-saturation with regard to the gypsum (CaS[O.sub.4], 2[H.sub.2]O) and the aragonite (CaC[O.sub.3]), the dolomite ([Ca.sup.++], [Mg.sup.++])[(C[O.sub.3]).sub.2] and of the anhydrite (CaSO4
) in all the watershed (Tab.1).
However, to maintain the total hardness, the salts of CaSO4
and MgSO4 (to increase hardness) while ethylenediaminetetraacetic acid (EDTA) and its sodium salt were used to decrease the water hardness.
Previous studies suggest that as the salt concentration in soil solution increases Ca2+ precipitates as CaCO3 and, to a lesser extent as CaSO4
, leaving preponderance of Na+ in soil solution that subsequently induces Na+ adsorption on the cation exchange sites (Suarez, 1981) and increases soil pH.
Careful observation of correlation coefficients among the ionic components suggests that NaCl, CaSO4
, MgSO4, MgCl2, HNO3, NH4NO3, NH4SO4 and (NH4)2SO4 are predominant species combinations.