Deterioration of soil health due to addition of muriate of potash (mop) fertilizer under an arid environment: a case study

Land salinization is one of the major desertification processes in Pakistan. Salinization occurs both naturally and as a result of human activities. Salinity has very adverse social, economic and health problems. Field studies were carried out to quantify the impact of addition of potassium chloride [muriate of potash (MOP)] fertilize on the accumulation and distribution of chloride in the soil profile. The treatments were consisted of 0, 57, 114 and 228 kg Cl ha/sup -1/ in form of MOP fertilizer. Cotton crop was used as test crop. The total quantity of applied irrigation water and total precipitation was 2581 m/sup 3/ ha/sup -1/ and 86 mm, respectively. Results showed that application of 228 kg Cl ha/sup -1/ raised the level of Cr from 4.9 to 7.2 meq L/sup -1/ in the upper 0-30 cm soil profile. Chloride content was higher at lower depths because of addition of 57 to 228 kg Cl ha/sup -l/ in the form of MOP. The addition K-fertilizer in the form of MOP raised the level of Cl content by 76.5 percent over added of the same quantity in the form of potassium sulphate [sulphate of potash (SOP)]. These studies show that continuous application of MOP would lead to accumulation of Cl in the soils. This is more particularly in the arid environment of Multan, where rainfall is scanty and insufficient to leach down Cl to the lower soil horizons. (author)