Three-dimensional stochastic simulation and uncertainty assessment on spatial distribution of soil salinity in coastal region

In order to illustrate the three-dimensional spatial pattern of soil salinity in coastal zones and provide relevant practical method and technical route, ordinary kriging and stochastic simulation method were applied to the estimation, simulation, comparison and uncertainty analysis of the three-dimensional spatial distribution of coastal soil salinity. The study was performed in typical farmlands of coastal reclamation zone in north Jiangsu Province, China. The results indicated that the spatial distribution of soil salinity generated by ordinary kriging was continuous and smooth, and the spatial variability of the kriging salinity data was reduced with the spatial structure changed, while the spatial distribution of soil salinity generated by the SGS (sequential gaussian simulation) was discrete and fluctuant. Soil salinity increased with the depth in soil solum across the study area and the risk of secondary-salinization was observed. The probability of soil salinization risk decreased since reclamation, and high probability region of slightly and medium salinized soil was the main area for amelioration and utilization. The study showed that stochastic simulation method revealed the three-dimensional spatial variability of soil attributes more truly than ordinary kriging method, and the research results can provide countermeasures to the management and utilization of salt-affected land in coastal reclamation zone.