Dynamics of soil salinity and vegetation in a reclaimed area in Saemangeum, Republic of Korea

The dynamics of soil salinity and vegetation in a reclaimed area in Saeamangeum were analyzed. The soil salinity, as measured by electric conductivity (EC) was monitored from 2014 (4 years after the tidal flat became land) to 2016. The average EC decreased during the three years (3.99, 2.85 and 1.92). The spatial distribution of EC was modeled using the Matérn isotropic model. The partial sill, the variance that can be modeled by a spatial model, decreased during the three years. The smoothness parameter that determined the shape of the variogram changed from 0.3 to 0.7 to 2 for the years studied. The results show that the spatial structure of soil salinity can be monitored more precisely using the Matérn model due to its flexibility. The relationship between vegetation indices and the EC for the three years was tested to figure out the effect of time lag on the relationship. The variation of vegetation indices was better explained by the EC of the previous year than of the year in which the image was taken. It takes a year for plants to colonize the desalinized area. Thus, the estimation using remote sensing data could be misleading if the time lag is not considered, particularly in a place where the environment changes rapidly.