Why did parts of Iraq’s drained southern marshes become salt flats?

Parts of Iraq’s southern marshes became salt flats primarily due to large-scale government drainage projects initiated in the late 20th century. By constructing extensive canals to divert water, the government drained approximately nine-tenths of the region's marshlands, which were once the largest wetland system in the Middle East.1

Once these areas were drained, they rapidly transformed into arid salt flats because of the environmental conditions inherent to the region. In arid climates, salts naturally accumulate in poorly drained soils when water evaporates from the surface or is transpired by plants, leaving behind mineral deposits. Without the constant flow of fresh water that previously maintained the wetlands, the high rate of evaporation caused alkaline salts to concentrate at or near the surface. This process of soil salinization is a persistent challenge in the region, often exacerbated by poor drainage and the lack of sufficient rainfall to flush salts downward through the soil profile.123