Investigation of Soil Physico-Chemical Properties in Playa Wetlands (Case Study: Daryacheh-Namak)

Soil, is a reclamable and sustainable source. it is the basis of survival and it's implication, should be performed on the basis of productivity identification according to scientific and technical rules, we can protect this valuable source, and increase it's productivity and usage. nowdays, saline soils cover nearly 14.6% of the country area. study areas (kashan' playa) have saline and alkali soils. identification of these soils and their's reclamation and implementation for differentusage, is very important, especially, they have abundant water resources. they have important influence on establishmentand development of plants. therefore, we started qualitative and quantitative pedological research. first, we prepared cover map as georeference with ilwis 3.3 software. we overlaied cover map and georeference geological map. we determined 12 working units, and then we took samples from units. physico-chemical factores such as ec, gypsum%, soluble cations and anions, organic matter, cac03 % and etc, determined from the depths of 0-10, 20-40, 40-80 of planttypes(working units, qm, qc) in february and july. result shows, na, mg, s04, k, ph, ci, c03, hc03, cac03, sar, cec rates decreased and gypsum and ca% rates increased, from the lake to uplans. also, the soil's texture was changed from clay sandy loam to sandy loam. at last, was drew soil's salinity map according to the soil taxonomy, it is in entisol order, aquent suborder, endo aquent greatgroup and typic endoaquent subgroup. according to the results, the soil isn'tsuitable for dry farming-and aquaculture (verybad class (class v)). study area, covered by halophyte plants and it will beappropriate to develop and 'improve with other halophytes. it should be protected from animals. especially camels that conserve soil structure and poor plant cover.