بررسي اثرات آبشويي در كاهش شوري و سديمي قسمتي از اراضي حاشيه كوير بجستان

The effects of leaching in decrease saline and sodic land in the margin of Kaveer Namak in Bajestan

Saline-sodic land in the margin of Kaveer Namak in Bajestan is one of the most important factors limiting agriculture in this region. In an attempt to examine the improvement of soil. A research project in the form of a fully random block project with five leaching treatments, 25. 50. 75. 100. cm water and marker in four interactions were performed. First, on four cubic meter plots in accordance with the trial plan the related leaching treatment was performed. After the soil moisture had reached the extent of field capacity, soil sample for analysis of the amount of saline existing in soil was prepared. From this analysis before and after the experiment, it is understood that soil classification before the trial was S4A4 and after applying various amounts of water it changed into S2A2. Precise determination of water amount for leaching requirement of every depth of soil is only possible through saline curves and dealkalization. Average of acidity (pH), electrical conductivity (EC) and exchange of soil percent (ESP) of the depth of one meter soil was respectively from 8.1, 39.1 ds/m and % 61 before leaching. to 8.4, 10.6 ds/m and %25 after applying one meter of leaching water had changed. and soil doesnot take the process of alkalization with respect to the relative light texture of soil, and bivalent salts dissolved in irrigation water and soil, It was concluded that for the improvement of these soils, thereis no need to soil conditioning agents and it is possible to improve them through using suitable water.