Soil inorganic carbon is the main carbon form in arid area. Its distribution can affect the pattern of carbon accumulation and storage in the soil profile. Due to the lack of soil profile data in deep soil layer

the carbon distribution and carbon storage characteristics of soil profiles are hard to accurately quantify

so the amount of inorganic carbon in soil is uncertain. This research was conducted on two typical kinds of land (farmland and uncultivated land) in the Sangong River watershed of Xinjiang

China. Soil profiles were sampled from topsoil to deep soil until to near shallow groundwater

and a total of 190 samples were obtained in six soil profiles. The distribution characteristics of soil inorganic carbon (SIC) and soluble salt ion in the sampled soils were analyzed

and the relationship between inorganic carbon and soil salinity was studied by redundancy analysis. The results revealed the following: (1) the SIC content of farmland was significantly higher than that of the uncultivated land (p <0.05)

and the SIC content of farmland increased by 27.9%

the range of change increased by 3.66 times compared with uncultivated land. Besides

the SIC contents of profiles in the uncultivated land and farmland were exhibited a distribution of "S" type and "M" type

respectively. (2) The soluble salt ions content of the farmland was significantly lower than that of the uncultivated land in the same soil layer (p <0.05)

and the distribution of soluble salt ions content in soil profile showed an increase- decrease trend in the uncultivated land

while a decrease trend in the farmland

and which indicated that the quantity and distribution characteristics of soluble salt ion content in soil profile were significantly changed by agricultural activities. (3) The reverse of soil inorganic carbon of all soil profiles followed the order of 0 - 100 cm soil layer < 100 - 300 cm soil layer < below 300 cm soil layer

and the values were significantly different among three soil layers

however

at same soil layer the proportions of soil inorganic carbon reverse were basically the same in uncultivated land and farmland

the values of three soil layers were 10%

35% and 55%

respectively （p<0.05）. (4) The order of the contribution of soil salinization factors to SIC was get through the redundancy analysis

and positive correlation was listed in the order of pH > ESP > SAR > CO32- > HCO3-

negative correlation was listed in the order of K+ > Ca2+ > Mg2+ > Cl- > Salt > SO42- > Cl- > Na+.