During his 24-year reign, Saddam decreed the extensive draining of the original 15,000-square-kilometer wetlands, in part to punish the Marsh Arabs who lived there and who opposed his rule. Adjoining nations also diverted some water further upstream.
In 2003 and 2004, an international group of wetlands experts led by Duke University ecologist Curtis Richardson was funded to conduct studies of the soils, water, plants and animals in the region.
Now, only 10 percent of the original marshes survived as "fully functioning wetlands" following extensive drainage and upstream agricultural irrigation on the Tigris and Euphrates during Saddam's rule, said a report authored by Richardson and four colleagues scheduled for publication in the Feb. 25 issue of the journal Science.
"This environmental disaster has been compared in scale to the drying up of the Aral Sea in Central Asia and to the deforestation of the Amazon," their report added. The Aral Sea, once the fourth biggest inland water body, is now mostly desert as a result of water diversions.
However, the authors also wrote that the remaining marshland could serve as a source for revitalization of the marsh ecology. "The high quality of water, the existing soil conditions and the presence of stocks of native species in some regions indicate that the restoration potential for a significant portion of the Mesopotamian marshes is high," said the report.
"The stakes are also high since the future of the 5,000-year-old Marsh Arab culture and the economic stability of large portions of southern Iraq are dependent on the success of this restoration effort," the report continued. The Marsh Arabs had been persecuted by Saddam.
In an interview, Richardson added: "I think the main outcome of this early research is to show that the marshes have much more resiliency than we thought, and that the potential for them to be restored is much higher."
Richardson is a professor of resource ecology at Duke's Nicholas School of the Environment and Earth Sciences. Other authors are anthropologist Peter Reiss of Development Alternatives, Inc., in Bethesda, Md.; fisheries biologist Najah Hussain of the University of Basra in Iraq; engineer Azzam Alwash with the Iraq Foundation in Washington, D.C.; and crop scientist Douglas Pool with the International Resources Group in Washington, D.C.
The research was funded by the United States Agency for International Development.
Once encompassing nearly twice the area of the original Florida Everglades, Iraq's Mesopotamian marshes served as habitats for millions of permanent and migrating birds, as well as a living filter for the wetlands' feeder rivers, the Tigris and Euphrates, the authors wrote.
Sometimes identified as the site of the fabled Garden of Eden, the wetlands have also served as a refuge for the self-sustaining Marsh Arabs. That culture has long fished and raised water buffalo in close harmony with its environment, living on artificial islands and within houses made of an indigenous reed called Phragmites australis.
Since Saddam was deposed, "uncontrolled" releases of some of the diverted river water by Iraqi citizens have combined with high rainfall and snowfall in the rivers' watersheds to re-flood nearly 20 percent of drained areas with varying results, their paper added.
The authors' photos depict some areas as flooded and well-vegetated, while others remain baked mudflats, salt pans or nonproductive scrublands. Satellite images from 1973, 2000 and 2004 also document the dramatic changes in the marshes.
The researchers' analyses of soil and water samples revealed excessive buildups of natural salts in some drained areas, especially nearest the Persian Gulf, that were high enough to impede return of marsh plant life upon reflooding. They also found abnormal buildups of selenium, a naturally occurring toxic metal.
But their limited testing did not support earlier reports that the marshlands had been chemically polluted with toxic organic compounds such as PCBs and pesticides.
And "water flowing into the marshes from the Euphrates and especially the Tigris was of higher quality than we originally hypothesized," the authors wrote. As a result of that water influx, the authors reported, a number of drained former marshes are showing signs of the early stages of restoration.
However, their observations indicated major declines in the numbers of native fish. Daily counts of bird species were low as well. And many key amphibians and mammal species were missing from some areas.
At the same time, the researchers reported increases in fish species introduced from other countries, some of those for aquaculture. ""We're really concerned now about the food pyramid for the fish, and the return of the native fisheries stock," Richardson said.
The Mesopotamian marshes are subdivided into three marshland areas. But by the end of Saddam's rule, satellite imaging revealed that only 3 percent of the Central Marsh and 14.5 percent of the Al-Hammar Marsh -- nearest the gulf -- remained intact.
Following the unregulated reflooding since then, the authors concluded that "restoration is occurring" in both those marshes, "but at different rates and species composition."
The scientists saw the most promise for the northern Al-Hawizeh Marsh, which straddles the Iranian border and was the least impacted by draining activities.
"The high water, low salinity and the presence of permanent lakes and dense vegetation" in surviving parts of Al-Hawizeh "give hope that this area can function both as a refugium and native repopulation center for the region," the authors concluded.
But their hopes for Al-Hawizeh were tempered by the possible impact of a new dike construction project that the scientists observed on the Iranian side of the remaining intact marsh. That project will "significantly reduce" water inflow into Al-Hawizeh, they predicted somberly.
More generally, the authors acknowledged that "it is unknown if sufficient water supplies can be can be made available, especially in drought years, to maintain long-term successful marsh restoration over large areas."