<<The Netherlands are reclaiming the ocean bottom which is below sealevel and
you are correct that it requires more salt tolerant organisms. Because the
Netherlands is below sea level, the normal drainage of rain water can't carry
the salts away as occurs above sealevel. >>
My understanding, gleaned from conversations in Holland, is that the Dutch
harvested and burned the grass, and extracted the salt from the ashes,
repeating the process until the soil became sweet. I have no written
documentation of this.