Abstract: Soil and water samples (3 246 soil samples and 78 water samples) were collected to study characteristics of soil salinity and indicative significance of soil salinity. Research shows that the degree of soil salinity is parallel to the coastline. The closer to the sea shore, the high content of salt is soil. Salt in the soil is mainly from four different sources: seawater immersion in the soil sedimentary process, the original salt in the sediments, the modern salt deposition in near surface soil, and the influence of human activity. The seawater immersion is the main reason to increase the soil salt content. Through Na-Cl exchange process, the formation mechanism of saline soil was analyzed in the water and soil system. Original salt in the sediment was analyzed by the scale factor method. A series of linear regression prediction models were established between the soil soluble salt contents of the well positions and the TDS. The regression between the Cl- in soil and the TDS was the most significant. This is related to that Cl- is a stable element and susceptible to soil adsorption. The regression prediction models were validated by HYRD1 well, and the accuracy was 96%. Taking HYRD1 well as an example, this paper explained the soil salt content role in multiple stratigraphic divisions based on the characteristics of littoralfacies sedimentary layers.
Key words：soluble salt; chlorine saline soil; regression analysis; TDS