Study

Vegetation response to re-flooding in the Mesopotamian Wetlands, southern Iraq

  • Published source details Hamdan M.A., Asada T., Hassan F.M., Warner B.G., Douabul A., Al-Hilli M.R.A. & Alwan A.A. (2010) Vegetation response to re-flooding in the Mesopotamian Wetlands, southern Iraq. Wetlands, 30, 177-188

Actions

This study is summarised as evidence for the following.

Action Category

Raise water level to restore/create brackish/salt marshes from other land uses

Action Link
Marsh and Swamp Conservation
  1. Raise water level to restore/create brackish/salt marshes from other land uses

    A before-and-after study in 1973–2006 of a brackish marsh in southern Iraq (Hamdan et al. 2010) reported that after reflooding, the marsh contained fewer plant species and communities than before it was drained, and that those communities typically had lower diversity and biomass. Statistical significance was not assessed. Within three years of reflooding, 38 plant species were recorded in the marsh (vs 48 before drainage). Twenty-six species were present both before and after reflooding. Three years after reflooding, 10 distinct plant communities were recorded in the marsh (vs 14 before drainage). For six of seven communities with comparable data, plant diversity was lower after reflooding than before drainage (data reported as a diversity index). Results for above-ground vegetation biomass were more mixed and depended on the season of comparison, but for six communities biomass was lower after reflooding than before drainage in at least one season (for which after: 50–3,247 g/m2; before: 60–4,923 g/m2). Methods: In 2003, local residents released water from canals and reservoirs to reflood marshes on the Mesopotamian Plain that had been almost completely drained in the 1990s. In spring and summer 2006, vegetation was surveyed in three sites within the slightly brackish (salinity 1–2 ppt) reflooded Central Marsh. Species, cover and biomass were recorded/collected in seven hundred 1-m2 quadrats. Biomass was later dried and weighed. Previously published data from the 1970s (from different sites within the marsh) were used for comparison.

    (Summarised by: Nigel Taylor)

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