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Changes in plant community composition resulting from ecological restoration can affect the spatial pattern and variability of soil salinity. Understanding and quantifying the temporal and spatial heterogeneity of soil salinity is essential before decisions can be made about the cost-effective management measures for plant communities following restoration on coastal saline filed. In this study, we selected three types of vegetation and conducted soil bulk electrical conductivity (ECb) by a hand held device in the topsoil (0–20 cm) at regular 1 m intervals across the field over a year period. Conventional statistics and geostatistics were used to analyze the data. The results showed significant differences and high coefficients of variation in top-soil salinity among different vegetation types. Simple mean ECb comparison revealed that soil salinity varied from spring to winter and tended to be higher in autumn. The generalized semivariogram for soil salinity indicated that woodland possessed a much smaller effective range (1.9 m) and nugget/sill ratio (7.37%) than that for other plant communities. Krigged contour maps showed different spatial distribution patterns among three types of vegetation and the consistently high and low salinity areas of the field at different seasons for the same vegetation. These results suggest that plant communities have significant influences on the temporal and spatial variability of soil salinity when vegetation is established in coastal saline field. The selection of plant species and management measures to plant should be special attention in the reclamation of saline land.

Ecological restoration by plants on coastal saline lands affects salt accumulation, distribution patterns and related mechanisms. In Chongmind Island, eastern China, we explored the way vegetation restoration affected the profile distributions of soil moisture and salinity in various seasons in naturally salt-affected coastal saline land. In four types of vegetation, five soil cores were acquired in the ∼ 80 cm depth range and the sampling depths of the five cores were respectively 0–10 cm, 10–20 cm, 20–40 cm, 40–60 cm, and 60–80 cm. Soil moisture firstly decreased and then increased with the depth in woodland and shrubland, while soil moisture consistently increased in grassland and control plots. Salt profiles showed the higher values in surface soil in control plots, whereas the pattern of soil salinity showed the reverse trend under vegetation. The effect of vegetation restoration on the profile distributions of salt is significant. In control plots, soil moisture and salinity showed a clear seasonal trend. Soil moisture values were the highest in spring and the lowest in autumn, when values of soil salinity were the highest in summer and the lowest in winter. Relative to control plots, the seasonal trend of soil moisture and salinity under vegetation appeared to be complex for no clear trend was observed. It can be concluded that plant communities significantly affect the spatial–temporal distribution of soil salinity. The selection of plant species is important in the reclamation of costal saline land.