Soils of Ba Lat estuary, Giao Thuy district were divided into 3 soil groups with 5 soil units, including 5 soil sub-units. Salic fluvisols group has largest area of 7,498.01 ha, accounts for 77.61 percent of total surveyed area and nearly 50 percent of total natural area, while fluvisols group has only 1,859.16 ha, accounts for 19.24 percent of total surveyed area. Arenosols group has smallest area of 303.71 ha, accounts for 3.14 percent of total surveyed area or 2 percent of district's total natural area. Typical character of salic fluvisols of Ba Lat estuary, Giao Thuy district is various soluble salt concentration. More than 71 percent of salic fluvisols has high salinity which has total soluble salt greater than 0.5 percent
the rest has mediwn and low salinity, with total soluble salt less than 0.5 percent. Salinity comes from chloride. Total concentration of substances varies from mediwn to rich. Fluvisols of Giao Thuy district is typical with light to mediwn soil texture, rich total nitrogen and phosphorous and mediwn total potassiwn. Acidity from light acid-medium to light alkaline. Entire area is slightly saline. Arenosols of Ba Lat estuary, Giao Thuy district has very light soil texture (the main content is sand), mediwn acidity, poor nutrients and low cation exchange capacity, nonnally less than 3 meq/100g soil.