Salt (specifically sodium chloride and other sodium compounds) is bad for soil because at higher levels it will cause soil aggregates to break down, collapsing soil pores and reducing the movement of water and air. Not only will the loss of soil structure result in reduced permeability, less water infiltration, and increased erosion, it will also cause puddling and topsoil saturation on level areas of the land. Additionally, when the surface dries, it will create a soil crust that prevents seedlings from breaking through[1].

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