Human Impact
The basins ecology has been fundamentally transformed since its riparian countries, Turkey, Iraq, Syria, Iran, and Jordan, entered into what they termed the Age of Dams in the late 1950s. The cumulative impact, including construction of more than 30 large dams, some built recently in Turkeys headwater region under the Southeast Anatolia Project (SAP), has been devastating. With the storage capacity of the larger dams exceeding the the Euphrates annual flow by five times and twice that of the Tigris, water supply to downstream wetland ecosystems has been substantially reduced and flood pulses, which had nourished the marshes, effectively eliminated. The situation is likely to worsen, as more dams are currently planned, with some already under construction.
A more acute cause for the loss of basin marshlands comes from a massive draining program implemented in southern Iraq, at the confluence of the Tigris-Euphrates system, after the Second Gulf War. Along with damming, the program has resulted in a marked degradation of water quality for the two rivers. Saline return drainage and discharge of polluted agricultural effluent has added to the adverse impact on marshland fertility and ecosystem processes. Of note however, is the fact that engineering of the drainage works in Iraq was made physically possible largely due to the reduced flow resulting from upstream impoundments.
Contamination from urban effluent is also considered part of the problem. Nevertheless, some hydrological experts suggest that the degradation of the basins marshland ecosystem is due solely to the long-term effects of water retention by dams.
Though the main reason for the damage is debatable, since 2001 there has been less cause to question its extent. That year scientists from the United Nations Environment Programme (UNEP) unveiled evidence from NASA satellite images of damage that had previously been difficult to ascertain due to the unstable situation in Iraq. Images show the Mesopotamian marshlands, which had previously covered an area of 15,000 to 20,000 square kilometers, reduced to one tenth of that area, later followed by further reductions. Two marshlands, the Central and Al Hammar, had already collapsed completely, transformed into salt-crusted bare land. A third, the Al HawizehHawr Al Azim, is now at high risk of suffering the same fate, due to upstream activities, including the recently completed Karkeh Dam in Iran and the planned Ilisu Dam in Turkey. Impact on wildlife has been equally devastating. Marshland desiccation has resulted in extinction and near extinction of several endemic species of mammals, birds, and fish. Inability of upstream habitats for migratory birds to compensate completely for loss of marshland wintering and staging sites, has reduced the population of an estimated 40 species of birds. Marine life in the Persian Gulf and the Shatt al-Arab estuary and coastal delta has been similarly disrupted. Coastal fisheries in the Persian Gulf have experienced marked reductions because of their dependence on the marshland habitat for spawning migrations and nursery grounds. In the Satt al-Arab areas, the ecosystem alterations have resulted from the decrease in freshwater flows and the reduced amount of sediment reaching the sea.
Estimates based on the satellite images taken over a decade ago determined approximately 90 percent of marshlands in this once Fertile Crescent had already been lost. According to UNEPs Tim Foresman, the importance of the damage to Mesopotamias wetlands cannot be underestimated.
Solution
Despite the extent of damage to the basin, scientists believe there is hope for amelioration of the situation. Progress is possible, provided (1) all riparian countries and stakeholders agree to a rational discussion of issues and remediation measures. Ramifications of allowing difficult political realities to interfere with this process are considered too dire to accept failure in this regard.
To this end, UNEPs Regional Office for West Asia (ROWA) has begun meeting with representatives from Iraq and Syria, the Arab Centre for the Studies of Arid Zones and Dry Lands (ACSAD), and the Regional Organisation for the Protection of the Marine Environment (ROPME). Aided by UNEPs proposed integrated scientific assessment and support from the global community, riparian countries are expected to establish international agreements for equitable and optimal use of the Tigris and Euphrates water systems, as well as similar pacts between Iran and Iraq regarding water-sharing between and among the Karkheh and Karun rivers and other Tigris tributaries.
Proposals include broad recommendations meant to promote basin-wide cooperation, (2) mitigate negative impact on the upper basin from dams, and restore wetlands. Efforts to mitigate the impact of dams and water works must be supported by dam developers and financial creditors adherence to policy guidelines recommended by the World Commission on Dams, as well as core provisions of the Untied Nations Convention on the Law of the Non-navigational Uses of International Watercourses.
To ameliorate the impact of dams, enough water flow to sustain life in downstream ecosystems must be ensured, and the role of water works must be reassessed. A long-term strategy would include at least partial (3) re-flooding of the delta area, facilitated by the development of an ecologically sound hydrodynamic model of the Tigris-Euphrates river system and its inland delta. Another option, used successfully in other countries, is to close the larger dams.
Shorter-term efforts should begin with (4) protection of water quality. Because of its bearing on the type of flora and fauna supported, controlling the quality of waters entering the marshlands is essential to restoration. Saline irrigation waters and urbanindustrial effluent pose the greatest threats, one from within Iraq, where influxes from the Tharthar and HabbaniyahRazaza reservoirs augment salt concentrations in the lower Tigris and Euphrates. Another need is to address the reduced fertility waters nourishing the marshes, created by dams (including the Karkeh) blocking sediment flow. Corrective measures in this regard will also benefit the natural evolutions of inland delta areas.
Further measures call for (5) Re-evaluation of River Engineering Works (6) Assigning Protected Areas and (7) Data Collection, Monitoring, and Long-Term Capacity Building. A comprehensive Environmental Impact Assessment of drainage and agricultural projects is needed, along with re-evaluation of massive off-river water storage reservoirs of the Tharthar and HabbaniyahRazaza. Modification or removal of diversion canals, dikes, and other hydraulic works inside marshlands may be necessary. Stabilizing the surviving Al HawizehAl Hawr Azim marshes is of utmost importance, calling for immediate attention by both Iraq and Iran. Suggestions include establishment of a trans-boundary peace park, a national reserve, or a UNESCO Man and Biosphere (MAB). Finally, detailed desiccation studies are needed to determine and monitor impact on wildlife and environmental conditions. Routine field data collection, aerial photography, and remote sensing imagery should be part of the monitoring program. Additionally, environmental administrations in Iran and Iraq need support, with wetland management and restoration training provided.
Flora and Fauna
Embodying Southwest Asias largest wetland ecosystem, the Mesopotamian marshlands have sustained a wide variety of rare and endemic flora and fauna. More than a few are of significant scientific and economic value.
When healthy, the majority of the Tigris-Euphrates wetlands are covered with vegetation, dominated by the common reed (Pharagmites australis), a large temperate and tropical perennial grass. The reed is gradually overtaken in the transitional season by reed mace (Typha augustata), a striaght-standing perennial with thick leaves. Temporarily flooded areas, or mudflats, support salt-tolerant vegetation, such as low sedges and bulrush (Carex and Juncus spp., Scripus brachyceras). Rich aquatic vegetation, such as hornwort (Ceratophyllum demersum), a free-floating plant pondweed (Potamogeton lucens spp.) and eel grass (Vallisneria sp.) are found in deeper, permanent lakes, along with bottom plants like stonewart (Chara spp.). Smaller lakes and back swamps support floating vegetation of waterlilies (Nymphaea and Nuphar spp.), water soldier (Pistia stratiotes), and duckweed (Lemna gibba).
As a major sanctuary of regional and global biodiversity, these marshlands also support a diverse population of wildlife. Situated on the inter-continental migratory flyway, they are of particular importance to birds. The marshlands are host to waterfowl traveling between breeding grounds in Siberias Ob and Irtysh river basins to wintering quarters in the Caspian region, Middle East, and northeast Africa. An estimated several million, including 134 species, of West Asias wintering wildfowl reside in Al Hammar and Al Hawizeh marshes. At least 11 of these species are globally threatened.
A few species are especially dependent on the marshlands for sustenance. These include the Dalmatian Pelican Pygmy Cormorant, a green-glossed black bird of medium size Marbled Teal, a gregarious, sandy-colored duck White-Tailed Eagle Imperial Eagle the Slender-billed Curlew and an endemic sub-species of the Little Grebe (Tachybaptus ruficollis iraquensis). The Goliath Heron, Sacred Ibis, and African Darter, all in danger of extinction, are also known to breed in these wetlands. As one of the few non-marine marsh areas in the world with Endemic Bird Area Status, they support nearly the entire population of the Basrah Redd Warbler, the Iraq Babbler, and the Grey Hypocolius.
Mammal populations have been under extraordinary pressure. Lions were exterminated by 1945, and three globally-threatened mammal speciesthe Grey Wolf, the Long-fingered Bat, and a subspecies of the Smooth-coated Otterinhabit the marshes. Rare by the 1980s, other large animals the Honey Badger, Striped Hyena, Jungle Cat, Goitered Gazelle, and Indian Crested Porcupine, also previously seen in the area, are now thought to be extinct. Fomerly common, the Wild Boar, is also now in decline. The Small Indian Mongoose, the Asiatic Jackal, and the Red Fox are among other often-spotted mammals. Common reptiles include the Caspian Terrapin, a soft-shell turtle, and a variety of snakes, including the over-hunted and now rare, Desert Monitor.
Previously comprising the bulk of Iraqs inland catch, many of the marshes fish are of scientific and economic significance. Dominant are those in the carp family (Cyprinidae), stomachless and toothless fish of special importance to the study of evolution. A number of species that spawn mainly in the marshes include the endemic and commercially valuable Gunther the endemic giant catfish, recognized by its small, flat head the Hilsa shad, and the pomphret. The seasonal migration of the penaeid shrimp, from the Persion Gulf, is of major commercial significance.
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