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Restoring the Garden of Eden: An Ecological Assessment of the Marshes of Iraq



The Mesopotamian marshes of southern Iraq had been all but destroyed by Saddam Hussein's regime by the year 2000. Earlier assessments suggested that poor water quality, the presence of toxic materials, and high saline soil conditions in the drained marshes would prevent their ecological restoration and doom the reestablishment of the Marsh Arab culture of fishing and agriculture. However, the high volume of good-quality water entering the marshes from the Tigris and Euphrates Rivers, a result of two record years of snowpack melt in Turkey and Iran, allowed 39% of the former marshes to be reflooded by September 2005. Although reflooding does not guarantee restoration success, our recent field surveys have found a remarkable rate of reestablishment of native macroinvertebrates, macrophytes, fish, and birds in reflooded marshes. However, the future availability of water for restoration is in question, which suggests that only a portion of the former marshes may be restored. Also, landscape connectivity between marshes is greatly reduced, causing concern about local species extinctions and lower diversity in isolated wetlands.
any consider Iraq’s Mesopotamian marshes
(figure 1a)—often referred to as the “Garden of
Eden”—to have been the cradle of Western civilization (Thesi-
ger 1964, Nicholson and Clark 2002). The word Mesopotamia
means “between rivers, referring to the location between
the Tigris and the Euphrates. These marshes were once the
largest wetlands in southwest Asia and covered more than
15,000 square kilometers (km
), an area nearly twice the size
of the original Everglades. However, as a result of a system-
atic plan by Saddam Husseins regime to ditch, dike, and
drain the marshes of southern Iraq, less than 10% of the
area remained as functioning marshland by the year 2000 (fig-
ure 1b; Partow 2001, Brasington 2002). The only remaining
marsh of any size was the northern portion of Al-Hawizeh (fig-
ure 1a, site 1), which straddles the border between Iran and
Iraq. The other two marshes, Central (also locally known as
the Qurna, or Central, marsh with the largest lakes; figure 1a,
site 2) and Al-Hammar (figure 1a, site 3), were virtually de-
stroyed by 2000. The remaining Al-Hawizeh was only 35% of
its 1977 size of 3076 km
by 2000 (figure 1b).
The loss of these ecologically critical wetlands was of added
concern because they were once home to 300,000 to 500,000
indigenous Marsh Arabs (Young 1977, Coast 2002). In 1991,
at the end of the first Gulf War, a populist uprising by the Shi’a
(the largest Muslim sect in Iraq) was crushed with brutal
force by the Sunni-controlled Baghdad regime. The military
raided settlements, killed at least tens of thousands of Marsh
Arabs—the actual number may be much higher—burned set-
tlements, killed livestock, and destroyed the core of the local
economy. The agricultural and fishing livelihood of the Marsh
Arabs was shattered. Persecuted and with no sustenance, tens
of thousands were moved to the edges of the drained marshes
or to the desert. More than 75,000 Marsh Arabs fled to south-
ern Iran and lived there in refugee camps for over 10 years
until Saddams regime fell (Nicholson and Clark 2002).
Most of the refugees had returned to Iraq by the end of
2004, but they found few viable marshes remaining. They had
virtually no chance of earning a traditional living by fishing
and raising water buffalo. Today, the Marsh Arab population
living near the marshes is estimated to be between 75,000 and
85,000, and those living actually within the marshes proba-
bly number fewer than 10,000 (DAI 2004). The remainder are
scattered in villages throughout the desert or are refugees in
the larger cities.
The marshes were also once famous for their biodiversity
and cultural richness. They were the permanent habitat for
millions of birds and a flyway for millions more migrating
between Siberia and Africa (Maltby 1994, Evans 2002). More
Curtis J. Richardson (e-mail: is an ecologist at the Nicholas
School of Environment and Earth Sciences, Duke University, Durham, NC
27708. His research has focused on wetland restoration and on wetlands as
nutrient sinks and transformers. Najah A. Hussain is an aquatic ecologist on
the faculty of the College of Science, University of Basrah, Basrah, Iraq. His
research has focused on water quality and on fish population dynamics. © 2006
American Institute of Biological Sciences.
Restoring the Garden of Eden:
An Ecological Assessment of
the Marshes of Iraq
The Mesopotamian marshes of southern Iraq had been all but destroyed by Saddam Husseins regime by the year 2000. Earlier assessments suggested
that poor water quality, the presence of toxic materials, and high saline soil conditions in the drained marshes would prevent their ecological
restoration and doom the reestablishment of the Marsh Arab culture of fishing and agriculture. However, the high volume of good-quality water
entering the marshes from the Tigris and Euphrates Rivers, a result of two record years of snowpack melt in Turkey and Iran, allowed 39% of the
former marshes to be reflooded by September 2005. Although reflooding does not guarantee restoration success, our recent field surveys have found a
remarkable rate of reestablishment of native macroinvertebrates, macrophytes, fish, and birds in reflooded marshes. However, the future availability
of water for restoration is in question, which suggests that only a portion of the former marshes may be restored. Also, landscape connectivity between
marshes is greatly reduced, causing concern about local species extinctions and lower diversity in isolated wetlands.
Keywords: functional assessment, Iraq, Mesopotamia, restoration, wetlands June 2006 / Vol. 56 No. 6 • BioScience 477
than 80 bird species were found in the marshes in the last com-
plete census in the 1970s (Evans 2002). Populations of rare
species such as the marbled teal (Marmaronetta angustirostris;
40% to 60% of the world population) and the Basrah reed
warbler (Acrocephalus griseldis; more than 90% of the world
population), which had been thought close to extinction
(Evans 2002), were recently seen in a winter bird survey (fig-
ure 2; Salmin et al. 2005). Coastal fish populations in the Per-
sian Gulf used the marshlands for spawning migrations, and
the marshes also served as nursery grounds for penaeid
shrimp (Metapenaeus affinis) and numerous marine fish
species. Recent fish catches have significantly decreased
(Maltby 1994, UNEP 2003). The marshlands also once served
as a natural filter for waste and other pollutants in the Tigris
and Euphrates rivers, thus protecting the Persian Gulf, which
has now become noticeably degraded along the coast of
Kuwait (Maltby 1994, Saeed et al. 1999, Partow 2001).
Although the Mesopotamian marshes had been almost
completely destroyed, it became clear on first inspection that
they were restorable, since they are a true “river of grass,
478 BioScience • June 2006 / Vol. 56 No. 6
Figure 1. (a) A composite view of the Mesopotamian marshlands from a mosaic of four Landsat 1 images and two false-color,
near-infrared images, 1973–1976. Dense marsh vegetation (mainly Phragmites australis) appears in dark red, seasonal lakes
in blue, agriculture in pink, and permanent lakes in black. The red elongated patches along riverbanks are date palms. The
three main marsh areas are Al-Hawizeh, Central, and Al-Hammar, labeled 1, 2, and 3, respectively. The city of Basrah is
located at number 4. Modified from Richardson and colleagues (2005). (b) A Landsat 7 Enhanced Thematic Mapper mosaic
taken in 2000. Most of the drained marshes appear as grayish-brown patches, indicating dead marsh vegetation or low desert
shrubs and dry ground. The white and gray patches indicate bare areas with no vegetation and, in some areas, salt evaporites
or shells covering the bottoms of former lakes. By 2000, 85% of the 8926 square kilometers (km
) of permanent marsh in 1973
marshlands had been destroyed. Only 3% of the Central marsh and 14.5% of the Al-Hammar remained. A canal known as
the Glory River (shown as a straight line across the top and down the east side of the Central marsh), constructed in 1993,
completely dried up the Central marsh by stopping water inflow from the Tigris River. The largest expanse (approximately
1025 km
) of remaining natural marsh, the Al-Hawizeh, near the Iranian border, is shown in dark red. Modified from
Richardson and colleagues (2005). (c) False-color image of the remaining Mesopotamian marshlands, taken 2 September
2005, shows in black the areas newly reflooded since the war. Reflooded areas adjacent to Al-Hawizeh, the western area of
Al-Hammar, and waterways in the northern and southern parts of the Central marsh are also visible in black. Al-Hawizeh
(called Hawr Al-Azim in Iran) is the best remaining natural marsh in the region. It straddles the Iraq–Iran border (yellow
line). During a field survey in February 2004, we discovered an Iranian dike under construction that is now nearly completed
and will traverse directly through the Al-Hawizeh marsh, along the Iraq–Iran border, and, as a result, will significantly
reduce the water input from the Karkheh and Karun rivers to the marsh. The ecological affects of this massive water diversion
are unknown, but it will significantly affect the last remaining natural marsh system in Iraq. Sampling sites: A, Al-Hawizeh;
B, Central; C, Al-Hammar; D, Al-Sanaf; E, Abu Zarag; F, Suq Al-Shuyukh. MODIS satellite image courtesy of the United
Nations Environment Programme, Iraq Marshlands Observation System.
wetlands fed by rivers and dominated by the aquatic grass
Phragmites australis. The first assessment of the status of the
marshes was done almost immediately after the fall of Bagh-
dad in June 2003 by a team of US scientists, who found that
massive but uncoordinated reflooding of the marshes was oc-
curring (Richardson et al. 2005). This early field analysis
concluded that water quantity and quality were sufficient to
restore some areas of the marshes and that a rapid reestab-
lishment of native plant species was occurring in some areas.
Still, many serious questions about the potential for restora-
tion remained:
What are the problems that could result from uncontrolled
reflooding of drained former marshes?
How serious are the problems of water quality (high levels
of pollutants, ions such as sodium [Na
]) and soil toxicity
(sulfide, sodic soils), which may prevent marsh restoration?
Can the native flora and fauna, including rare or endan-
gered species, reestablish in marshes that had been drained
for over a decade and isolated from native populations?
Could marsh health be assessed accurately after only two
years of reflooding?
Will there be enough water to restore the marshes, given
competing national and international demands on water?
Most important, would the Marsh Arabs return to live
once more in the marshes, given the complexity of resettle-
ment problems?
The objectives of this article are to update some of our
earlier findings by analyzing the last two years of field data
collected by US and Iraqi scientists and to provide new
answers, where possible, to the questions above.
An approach for assessing marsh restoration
The vast amount of former marsh area prevented us from
completing a detailed ecological analysis of all the reflooded
sites. To cover the three historic marsh areas (Central, Al-
Hawizeh, and Al-Hammar), we selected four very large
marshes: Al-Hawizeh, the only natural remaining marsh on
the Iranian border; the eastern Al-Hammar marsh; Abu Zarag
(western Central marsh); and Suq Al-Shuyukh (western Al-
Hammar) (figure 3). From 2003 until 2005, we monitored
water quality, water depth and transparency, soil chemistry
conditions, and ecological indicators of plant and algal pro-
ductivity, and we surveyed the numbers and species of birds,
fish, and macroinvertebrate populations. (For a detailed
analysis of the field and laboratory chemistry methods and
statistical analyses used in this article, see DAI 2004, Richard-
son et al. 2005.) This original work was done in conjunction
with Iraqi scientists to assess the ecological and environ-
mental conditions present where the dominant flora and
fauna in the natural Al-Hawizeh still existed and to compare
these conditions with those of three marshes reflooded in 2003.
To provide an estimate of overall ecosystem health, we com-
pleted an ecosystem functional assessment (EFA) to determine
restoration progress to date and to establish how the newly
reflooded marshes were functioning compared with the nat-
ural marsh and with historical values.
In the EFA method, indicators of ecosystem function are
grouped into five ecosystem-level functional categories: hy-
drologic flux and storage, biological productivity, biogeo-
chemical cycling and storage, decomposition, and
community/wildlife habitat (Nunnery 1997, Richardson and
Nunnery 2001). Next, a carefully chosen set of variables rep-
resenting these five functional categories are selected as key
Articles June 2006 / Vol. 56 No. 6 • BioScience 479
Figure 2. Two globally vulnerable species, marbled teal (Marmaronetta angustirostris, left) and Basrah reed warbler (Acro-
cephalus griseldis
right), photographed in 2005 in the Iraq marshes by Iraqi nature photographer Al Salim. Photographs
courtesy of the Canadian International Development Agency and Mudhafar A. Salim (
indicators to be measured in the affected ecosystems and in
a set of reference ecosystems. Key indicator values obtained
in the field from the affected ecosystem are scaled against those
from reference ecosystems to determine whether there are sig-
nificant shifts in these indicators (Richardson and Nunnery
2001, Richardson et al. 2003, Richardson 2005). Our EFA
analysis of the marshes was somewhat compromised in terms
of the collection of the most appropriate key indicators for
each function because of the difficulty of sampling in re-
mote and dangerous areas of Iraq. Thus, our estimates of
ecosystem health are less quantitative than a standard EFA. The
current research and monitoring is being carried out primarily
by two Iraqi research teams from the University of Basrah, sup-
ported by the US Agency for International Development
(USAID), and by the New Eden project, supported by Italian
government funds and the Canadian International Devel-
opment Agency. The total international funding to date for
marsh restoration is slightly in excess of $30 million, a minis-
cule amount compared with the billions being spent in Iraq
for other purposes.
Problems with marsh reflooding
Almost immediately after the collapse of the Hussein regime
in April 2003, local farmers and water ministries began blow-
ing up dikes and earthen dams or otherwise releasing water
back into the former marsh areas through control structures.
(See figure 1c for reflooded areas; ground views of the nat-
ural, reflooded, diked, and drained sites are shown in figure
3.) By February 2004, nearly 20% of the 15,000 km
of the for-
mer drained marshes had been reflooded. More recent esti-
mates from the Iraq Water Ministry and from UNEP (United
Nations Environment Programme) satellite photos indicate
that by 2005, 39% of the destroyed marshes had standing
water; also noteworthy, a trend analysis of vegetation re-
growth from January 2003 until September 2005 indicated that
vegetation cover was expanding at 800 km
per year (UNEP
480 BioScience • June 2006 / Vol. 56 No. 6
Figure 3. (a) Marsh Arab fishermen collecting reeds (Phragmites australis) in the natural Al-Hawizeh marsh (N 31°38.583,
E 47°35.203) near the Iranian border in June 2003. (b) The totally drained Central marsh near Chibayish (N 30°58.102,
E 47°09.033) in June 2003. An Iraqi engineer from the Ministry of Water Resources is viewing the cracked and desiccated
marsh soil adjacent to a dried-out streambed. (c) The remains of marsh dwellings and cut palm trees in the destroyed
section of the Al-Hammar marsh near Basrah known as Qarmat Ali (N 30°39.561, W 47°39.230). The area was reflooded in
April 2003 when local tribes broke the earthen dam holding out the water for this section of the marsh. (d) Al-Sanaf, a
seasonal marsh area (N 31°92.491, E 47°12.674) that is used to take overflow water from the Crown of Battles River. It has
extremely high salinities (see table 1) and ion concentrations, including toxic levels of selenium, due to a lack of proper
outflow drainage and high evapotranspiration (Richardson et al. 2005). High ion concentrations have prevented the estab-
lishment of native marsh vegetation. (e) Abu Zarag in February 2004 (N 31°07.583, E 46°37.422). This area was reflooded
in April 2003. The area has seen a rapid recovery of marsh vegetation and algae. Fishing was good in the spring of 2004
and 2005. (f) A Marsh Arab woman collecting reeds for fodder near her island village in Suq Al-Shuyukh in February 2004
(N 30°51.491, E 46°40.398). This marsh was among the earliest to be reflooded, in early 2003, and has excellent reed re-
growth; thus, it is the major location where Marsh Arabs have returned to live on traditional “floating islands” with their
water buffalo (Bubalus arnee). Photographs: Curtis J. Richardson.
2005). However, wetland habitat fragmentation (discon-
nected patches), one of the most commonly cited causes of
species extinction (Wiens 1996), and ensuing loss of biolog-
ical diversity are quite evident when surveying the distance
between reflooded marshes (figure 1c). The sparsely vegetated
reflooded areas are very scattered compared with the con-
tiguous wetland landscape found in 1973 (figure 1a; Al-Hilli
1977). In addition, many of the former water flow connections
between marsh patches are now blocked by dikes and canals.
Landscape connectivity, the inverse of landscape fragmenta-
tion (Urban and Keitt 2001), is now considerably reduced,
which can have significant effects on population survival
(Fahrig and Paloheimo 1988) and metapopulation dynam-
ics (Levins 1970) for macroinvertebrates, fish, amphibians, and
even plants.
Although the uncontrolled reflooding is welcome news, it
presents potential problems and challenges regarding the
quality of water:
The release of toxins from reflooded soils that are contami-
nated with chemicals, mines, and military ordnance
Flooding of local villages and farms now developed on the
edges of formerly drained marshes
A false sense of security regarding the volume of water that
will be available to restore the marshes in future years
All these problems have come to light in the past two years.
Toxic levels of sulfides and salts have been reported in a few
areas of the reflooded marshes (Fitz-
patrick 2004, Richardson et al. 2005).
Minefields exist throughout the marshes
along the border of Iran, and a number
of villages were flooded by the destruction
of dikes and dams (C. J. R., personal ob-
servation). Marsh restoration has been
further complicated by the construction
of more than 30 dams and several thou-
sand kilometers of dikes in Iraq during
the past 30 years. This infrastructure has
resulted in the retention of large volumes
of water in the central portions of Iraq for
cities and agriculture, as well as in the
reduction of new sediment accumula-
tion in the marshes (Partow 2001, Nichol-
son and Clark 2002). During the past
two years, high snowmelt from the moun-
tains of Turkey and Iran has resulted in
near record flows on the Tigris and Eu-
phrates rivers, resulting in vast amounts
of excess water being available for re-
flooding of the marshes (Partow 2001,
Richardson et al. 2005), but it is unknown
how long this pattern of increased water
release will last.
Another issue that is not clearly understood by many en-
gineers and water managers is that reflooding does not equal
wetland restoration. While the presence of adequate water is
critical to marsh restoration, the restoration of wetland func-
tions requires also the proper water hydroperiod (period of
time water is at or near the surface), hydropattern (distribu-
tion of water over the landscape), and good water quality.
These conditions are complex in nature. Restoration projects
that do not take this complexity into account can at first
seem to be successful, but they are later recognized as failures
because conditions promoting important ecosystem functions
have not been adequately restored (Zedler and Calloway
1999, Richardson and Nunnery 2001). For example, in his-
toric times the pulsed flow of water, sediments, and nutrients
into the Iraqi marshes came via the spring melt. Massive
flooding was the most common condition during this period,
with marsh expansion from 15,000 to 20,000 km
, followed
by a decrease in marsh area by as much as 30% to 50% dur-
ing the summer as a result of high evaporation rates (> 200
centimeters [cm] per year; Buringh 1960). During the sum-
mer, the Marsh Arabs planted their rice and barley crops at
the marsh edges and used the annually rejuvenated marsh soils
to produce their crops. The water flow was continuous
through the year, and it was this flow that kept the salinity con-
centrations low and prevented the buildup of potentially
toxic elements, such as selenium and salts, that was seen in the
diked areas of Al-Sanaf (figure 4; Richardson et al. 2005). Now,
dams, dikes, and canals prevent the overflow of water at the
marsh edges, thus reducing the historical inundation pattern
of the marshes.
Articles June 2006 / Vol. 56 No. 6 • BioScience 481
Figure 4. A monthly comparison of salinity patterns in the natural Al-Hawizeh
marsh and in three reflooded marshes (Al-Hammar, Suq Al-Shuyukh, and Abu
Zarag) after 12 to 18 months of water additions. Data are from researchers from
the University of Basrah and the Eden Again Project.
Water quality and soil chemistry conditions
The idea that only 15% to 20% of the drained wetland could
be restored because of excessive salinity, environmental pol-
lution, a lack of available high-quality water, or a loss of na-
tive species (Partow 2001, EA ITAP 2003) was quickly dispelled
by our 2003 and 2004 field surveys (Richardson et al. 2005).
Water quality in the Tigris and Euphrates, which flow into the
marshes, was much better than earlier thought (table 1). The
natural Al-Hawizeh marsh (figure 3a) had the lowest con-
centration for all major ions, and the total phosphorus (P) in
surface water was close to river water values (table 1). Dissolved
organic carbon was highest in the drained and highly oxidized
marsh outflows, while the natural site and river waters demon-
strated much lower values. The reflooded eastern Al-Hammar
site (figure 3c) had the highest total P, which may be related
to sampling at several sites where human and animal waste
was released directly into the water column without treatment.
Total nitrogen was highest at the Al-Sanaf site (figure 3d), an
area where nitrogen-fixing blue-green algae were seen to be
dominant in the water column, even at higher salinities (Al-
Mousawi and Whitton 1983). All upstream and marsh sur-
face waters were highly oxygenated, but oxygen was
significantly reduced (P < 0.05) in the Shatt Al-Arab, where
untreated wastewater is currently being released from cities
such as Basrah. Salinity, conductivity, and concentrations of
total dissolved solids (TDS) were low, and pH was between
7 and 8 at all sites except for the enclosed Al-Sanaf, where these
variables were significantly higher (P < 0.05). The restricted
water outflows in the Al-Sanaf, coupled with high regional
evapotranspiration rates, have resulted in extremely high ion
concentrations, pH, and TDS (table 1), values similar to
those measured in highly salinized portions of the Jordan River
(Farber et al. 2004). Results from Al-Sanaf suggest that sim-
ply adding water to former marshes without providing for con-
tinual flushing will result in excessive salinity and toxicity prob-
lems (Richardson et al. 2005).
Fortunately, a year-long survey of the salinity of the three
restored marshes, when compared with the natural Al-
Hawizeh, indicates that these restored areas are maintaining
very low salinities after nearly two years of reflooding (figure
4). Salinities generally showed a seasonal summer peak due
to high evapotranspiration but were below 3 parts per thou-
sand (ppt). The two lowest areas of salinity, the natural Al-
Hawizeh and Abu Zarag, both have lower-salinity Tigris
water as their source, compared with the higher-salinity Eu-
phrates, which feeds the other two sites. Al-Hammar had
the highest concentrations of most constituents, which indi-
cates that this reflooded site is more saline and chemically en-
riched than the other two sites, since it now receives tidal
seawater from the Persian Gulf (Richardson et al. 2005).
However, our current water chemistry values, when compared
with historical surveys completed before drainage in the Al-
Hammar marsh (Maulood et al. 1981, Banat et al. 2005), re-
vealed an increase in conductivity (240%), TDS (140%),
(170%), magnesium (Mg
; 158%), calcium (Ca
240%), chlorine (Cl
; 160%) and bicarbonate (HCO
180%) in the Suq Al-Shuyukh region during the past 20 years
(Richardson et al. 2005). In contrast, measured salinities in 1981
(Maulood et al. 1981) from seven locations in the undrained
Central marsh averaged 0.6 ppt (± 0.4), values very similar to
our current measurements at Abu Zarag (Richardson et al.
Worldwide, the highest numbers of species are found in
aquatic environments below a salinity of 5 ppt (Wetzel 2001).
Collectively, our studies indicate that the reflooded portions
of the western Al-Hammar at Suq Al-Shuyukh and eastern
Al-Hammar have experienced increases in saline conditions
but are still well below the concentrations that affect most
482 BioScience • June 2006 / Vol. 56 No. 6
Table 1. Water quality at selected river and marsh locations in southeast Iraq, June 2003.
Upstream Tigris Downstream
and Euphrates Al-Hawizeh Al-Hammar Al-Sanaf Shatt Al-Arab
Constituent (rivers) (natural marsh) (reflooded marsh) (reflooded marsh) (river)
Salinity (ppt) 0.77
(0.05) 0.87
(0.04) 0.96
(0.03) 17.49
(0.45) 2.13
Conductivity 1.55
(0.11) 1.74
(0.06) 1.91
(0.06) 28.41
(0.61) 4.10
(mS per cm)
pH 8.14
(0.09) 7.64
(0.16) 7.95
(0.06) 9.40
0.01 7.51
Dissolved oxygen 8.11
(1.67) 7.71
(1.39) 7.03
(0.06) 8.79
(0.67) 4.89
(mg per L)
Total dissolved solids 1.01
(0.07) 1.13
(0.04) 1.24
(0.04) 18.46
(0.40) 3.02
(g per L)
Total nitrogen 763
(470) 464
(0.04) 1,652
(546) 2,050
(205) 849
(µg per L)
Total phosphorus 112
(47) 133
(27) 657
(1174) 93
(22) 147
(µg per L)
Dissolved organic carbon 4.79
(2.10) 4.68
(0.70) 13.92
(7.91) 37.86
(1.00) 4.95
(mg per L)
cm, centimeter; g, gram; L, liter; mg, milligram; µg, microgram; mS, millisiemens; ppt, parts per thousand.
Note: Different letters indicate a significant difference (P < 0.05) across sites and the same letter indicates no significant difference among sites as
determined by least significant difference test. Standard errors of the mean are shown in parentheses.
freshwater species. The long-term rates of salinity increases
are unknown, but present levels are within the normal vari-
ation found in the marshes between the wet season and the
dry season (Al-Hilli 1977, Hussain 1992, Richardson et al.
2005). The cause for this increase in salinity is unknown,
but it probably relates to a rise in salinity in the Euphrates and
to increased flux into the water column of ions concentrated
in the soil after 10 years of drainage and evaporation. In the
case of eastern Al-Hammar, breaches in dikes in 2003 al-
lowed more tidal seawater to flow from the Shatt Al-Arab into
the marsh.
Analyses of surface water and soils for organochlorine
pesticides, polychlorinated biphenyls, and polycyclic aro-
matic hydrocarbons (PAHs) showed no detectable concen-
trations of any of these xenobiotics (Richardson et al. 2005).
However, recent surveys in Abu Zarag have found low mol-
ecular weights of PAHs in Abu Zarag soils, probably as a re-
sult of the severe burnings in the region (DouAbul et al.
2005). These findings are in contrast to earlier reports of
higher chemical pollution in the marshes and rivers (DouAbul
et al. 1988, Saeed et al. 1999) and proba-
bly reflect the lack of pesticide use in the
drained marshes, reduced chemical re-
leases into water bodies during the war, or
our limited sampling regime. Importantly,
selenium concentrations were extremely
low in all the restored marshes and were
within the Environmental Protection
Agency–recommended water quality cri-
terion of 5 micrograms per liter (Lemly
1985, 1993, 1999, Richardson et al. 2005).
Large differences occur in the physical
and chemical characteristics of the natural,
diked, drained, and reflooded marsh soils
as shown with principal component
analysis (PCA; figure 5). The first three
principal component axes were signifi-
cant, according to the broken-stick eigen-
value test (Legendre and Legendre 1998),
and together they accounted for 71% of
the variance in the data. The PCA re-
vealed that marsh alteration may have re-
sulted in significant changes in soil
chemistry and moisture, with the re-
flooded but diked Al-Sanaf marsh having
much higher salinities, higher sulfate (SO
levels, and lower soil moisture than the
natural marsh site. Surprisingly, the
Central marsh still retained the highest soil
organic matter after more than 10 years of
drainage and extensive fires. The soil
chemistry of the reflooded Al-Hammar
marshes had higher salinities than the
other restored sites, which, as mentioned
earlier, reflects the influence of tidal
water input. The restored sites at Suq Al-
Shuyukh and Abu Zarag and the natural Al-Hawizeh sites were
found in the same general ordination space, with more soil
moisture, higher exchangeable P, and increased microbial
biomass carbon. Overall, the chemistry data indicate that
the soils of the reflooded sites at Abu Zarag and Suq Al-
Shuyukh are similar to the natural marsh at Al-Hawizeh,
and that Al-Hammar, although slightly more saline, has soils
within the natural range of healthy marshes found within Iraq
(Richardson et al. 2005). (Importantly, some of the chemical
differences measured among marsh sites are due to variations
in soil type and geology found across southern Iraq, and
thus not all of the variations can be attributed to drainage;
Buringh 1960.)
However, restoration may be difficult in some localized
areas, because soil conditions and water quality in the drained
and diked (as compared with the reflooded and natural)
marshes clearly demonstrated massive shifts in ion chemistry
and structure. For example, many areas of the marshes were
severely burned after drainage. The intensity of the burns in
some areas, with high surface organic matter covering sulfidic
Articles June 2006 / Vol. 56 No. 6 • BioScience 483
Figure 5. A principal component analysis (PCA) of the marsh soils from drained
(Central), diked (Al-Sanaf), restored (Abu Zarag, Suq Al-Shuyukh, Al-Hammar),
and natural (Al-Hawizeh) marshes of southern Iraq. Axis 1 accounted for 32.2%,
axis 2 accounted for 22.1%, and axis 3 accounted for 16.9% of the total variance
(not shown). Soil properties with strong negative loadings on axis 1 included per-
centage of carbon (%C), soil organic matter (SOM), and nitrogen species, while
extractable aluminum (Al) and iron (Fe) as well as well as soil moisture, potas-
sium (K), and pH had a strong positive loading on axis 1. A number of soil proper-
ties, including salinity, sulfate (SO
), and exchangeable calcium (Ca), had strong
positive loadings on axis 2 and showed distinct differences among marsh sites,
especially between the Al-Sanaf and the natural Al-Hawizeh. The highest ex-
tractable phosphorus (bicarbonate; P
) was found in the natural Al-Hawizeh.
Abbreviations: MBC, microbial biomass carbon; Mg, magnesium; NH
nium; NO
, nitrate.
pyrite soils beneath, resulted in soils being greatly altered
chemically and then exposed to oxygen for decades of drain-
ing, resulting in the formation of sulfuric acid (Fitzpatrick
2004). These highly oxidizing conditions liberate iron (Fe),
Ca, Mg, and trace elements like copper as well as producing
toxic conditions and sodic or calcic soils when reflooded.
Moreover, Fitzpatrick’s X-ray scanning electron microscopy
work (2004) suggests that the burned soils where iron sulfide
) has been converted to iron oxide maghermite (Fe
now have a texture like ceramic, meaning that the soil will not
rewet and cannot support plant life. The soil chemistry analy-
sis results suggest that reflooded and drained marsh areas can
be restored, but some locations will have excessive salt accu-
mulation problems, toxic elements, and severe water quality
degradation, with a concomitant loss of native marsh vege-
tation. It is imperative that these areas be identified so that the
limited water supplies can be used to restore those areas with
the most promise for full restoration.
Ecological recovery of native flora and fauna
One year after reflooding, species recovery was occurring in
all three former marshland sites (Abu Zarag, Al-Hammar, and
Suq Al-Shuyukh), but with varying degrees of success and at
different successional rates (Richardson et al. 2005). A biotic
2004–2005 survey from the Al-Hammar and Suq Al-Shuyukh
marshes indicated that most macrophyte, macroinvertebrate,
fish, and bird species were returning to the restored marshes,
although densities were low compared
with historical records (figure 6). The rea-
son for the early return of many species is
probably directly related to the reintro-
duction of propagules, seeds, larvae, and
fish stocks directly from the overflow river
waters of the Tigris and Euphrates.A list-
ing of the five most common species of
plants, birds, and fish found in Al-Hawizeh
as compared with Suq Al-Shuyukh and Al-
Hammar reveals that Al-Hammar and
Suq Al-Shuyukh are most similar, while
Al-Hammar differs from the other two
marshes in dominant species composi-
tion (table 2). This difference in species is
probably related to the tidal influence
(higher salinity) now found in Al-
Hammar (figure 4). A full comparison of
all species surveyed reveals slightly dif-
ferent trends.
Al-Hawizeh had the lowest number of
dominant macrophyte species (6) and
was dominated by P. australis stands and
hornwort (Ceratophyllum demersum) in
the open water areas (figure 3a), whereas
Al-Hammar had nearly double the num-
ber of plant species (10) as a result of the
influence of more salt-tolerant plants
(figure 6). Collectively, the restored sites
had 15 species, a number close to historic values; however, a
number of nondominant species found by Al-Hilli (1977) in
his extensive survey of the marshes have not been recorded
in recent studies (figure 6). Surprisingly, a Jaccard similarity
analysis of all plant species, including nondominants, indicated
that Al-Hammar and Suq Al-Shuyukh were most similar to
Al-Hawizeh (Jaccard index [C
] = 0.45 and 0.42, respec-
tively); the macrophytes at Suq Al-Shuyukh were the most dis-
similar to those at the natural Al-Hawizeh (C
= 0.23). Over
100 species of macroinvertebrates were found in the three
marshes, and surveys indicate the presence of the main species
of arthropods (including crustacea) and mollusks reported
in the past (Hussain 1992, Scott 1995), with numbers of in-
dividuals per unit area 1.5 times greater at the open-water Suq
Al-Shuyukh sites than at the densely vegetated Al-Hawizeh
(Richardson et al. 2005). Suq Al-Shuyukh has the highest
number of species (more than 60) and Al-Hammar the low-
est (42). The highest Jaccard similarity was found between Al-
Hawizeh and Suq Al-Shuyukh (C
= 0.41). All numbers are
below historic values. Macroinvertebrate abundances at all
marsh sites were dominated by snails (Lymnaea spp.) and bee-
tles (Coleoptera).
The highest number of fish species (23), found at Al-
Hammar, represented 72% of the historic number (32, in-
cluding 23 freshwater and 9 estuarine species), and the
lowest number (15) were found at Al-Hawizeh (figure 6). The
highest Jaccard similarity for fish was found between Al-
484 BioScience • June 2006 / Vol. 56 No. 6
Figure 6. A comparison of numbers of macrophyte, fish, and bird species recorded
in one natural marsh (Al-Hawizeh), two reflooded marshes (Al-Hammar and Suq
Al-Shuyukh), and current and historical records for all three marshes combined.
Current data for macroinvertebrates are presented for comparison among sites,
but no reliable historical quantitative records exist for these organisms. Abbrevia-
tion: ND, no data.
Hawizeh and Suq Al-Shuyukh (C
= 0.73). If
marine species were excluded, the similarity
value rose to C
= 0.94. The similarity between
Al-Hawizeh and Al-Hammar was 0. 65. A more
detailed survey of fish species composition and
size, assessed in conjunction with local fish mar-
ket data, indicates that bunni (Barbus sharpeyi)—
the most important historic endemic fish species
with the highest commercial value—is present
in all the marshes, but in greatly reduced num-
bers and size (Richardson et al. 2005). Carassius
carassius, an introduced carp species from Iran,
comprised 20% of the summer 2004 catch in Suq
Al-Shuyukh but up to 46% of the catch in Al-
Hawizeh. A survey of the fishermen of the villages
(DAI 2004) also indicated that fishing is ex-
tremely poor because of the small size of the
fish and because Silurus triostegus, a carnivo-
rous catfish species (40 to 55 cm in length) not
eaten by the local Shi’a population for religious
reasons, can comprise up to 60% (by weight) of
the catch. The current domination by a pisciv-
orous species like Silurus rather than herbivorous
Barbus species is also due in part to prolonged marsh drying
and a lack of food resources (algae, aquatic plants, and
macroinvertebrates) for the herbivorous fish species. The re-
sult is an imbalanced fish pyramid, which may have serious
impacts on any attempts to restore normal fish population
structure in the marshes. The return of marketable fish to the
marshes is critical to the livelihood of the Marsh Arabs and
the establishment of successful new villages in the interior of
the marsh. This is one of the main reasons to date why vil-
lage resettlement of the marshes has occurred in only a few
locations, such as Suq Al-Shuyukh. In March 2004, fishermen
reported to us that their livelihood from fishing at that time
was very poor, but conditions improved slightly by the sum-
mer of 2005. Work is currently under way through USAID to
provide fish stocks for the marshes through an aquaculture
program (DAI 2004).
The bird survey in the three marshes in 2004 found a
total of 56 species, compared with historical counts of 84
species (Scott 1995). The natural Al-Hawizeh marsh had the
most species (53), nearly matching our total count of 56 for
all the marshes surveyed (figure 6). Al-Hammar had the low-
est species number (29), which was slightly more than half the
total species identified. The highest Jaccard similarity was
found between Al-Hawizeh and Suq Al-Shuyukh (C
= 0.64).
Daily summer counts of individual birds per species were low
(< 50 birds) except for little egret (Egretta garzetta), squacco
heron (Ardeola ralloides), and the threatened pygmy cor-
morant (Phalacrocorax pygmeus), found in Al-Hawizeh; how-
ever, winter counts increased dramatically in the winter of
2005. Importantly, the highly threatened endemic Iraq bab-
bler (Turdoides altirostris), a species not seen in a more than
a decade, and the marbled teal (Marmaronetta angustirostris),
another highly threatened species, were seen in the reflooded
wetlands, but in low numbers (figure 2). One indication of
marsh recovery is that nearly half of the bird species were
recorded as breeding in the marshes during the summer of
2004 and 2005. Another indication of bird habitat restoration
is that a more complete survey of 28 marsh areas in the win-
ter of 2005, conducted by the Canadian–Iraq Marshlands
Initiative, recorded 74 bird species, including 10 rare and
endangered species not seen in over 25 years (Salmin et al.
A functional assessment of ecosystem restoration
We had sufficient data to complete an EFA on only two of the
restored marshes. We compared their structure and func-
tions with the remaining natural Al-Hawizeh as well as with
recorded historical values for Iraqi marshes (Nunnery 1997,
Richardson and Nunnery 1998, 2001, Richardson et al. 2005).
In the EFA method, indicators of wetland structure and func-
tions are measured in five ecosystem-level categories: hydro-
logic flux and storage, biological productivity, biogeochemical
cycling and storage, decomposition, and community/wildlife
habitat. Because of the difficulty of data collection, we were
limited in our ability to use long-term indicators. Given this
limitation, we chose metrics best representing the five eco-
system functional categories to give an overall qualitative
assessment of marsh functioning.
The EFA analysis revealed that Suq Al-Shuyukh has nearly
recovered all its key functions when compared with the re-
maining natural Al-Hawizeh marsh (e.g., Phragmites plant
production was 83% of that at Al-Hawizeh, and a crude
index of decomposition/redox status as indicated by oxygen
in the water column was 93% of the value at the natural
marsh), whereas Al-Hammar has severely reduced water
transparency (41% of Al-Hawizeh levels) and lower numbers
Articles June 2006 / Vol. 56 No. 6 • BioScience 485
Table 2. A list of the five most common or abundant species of bird, fish,
and plant species in three different marsh areas, based on surveys done by
faculty and students at the University of Basrah, 2003–2005.
Al-Hawizeh Suq Al-Shuyukh Al-Hammar
(natural marsh) (reflooded marsh) (reflooded marsh)
Bird species
Phalacrocorax pygmeus Egretta garzetta Egretta garzetta
Egretta garzetta Ceryle rudis Larus ridibundus
Tachybaptus ruficollis Ardeola ralloides Larus genei
Larus canus Ardea purpurea Larus canus
Larus ridibundus Vanellus leucurus Sterna albifrons
Fish species
Barbus luteus Liza abu Liza abu
Aspius vorax Carassius carassius
Liza carinata
Carassius carassius
Barbus luteus Carassius carassius
Barbus sharpeyi Aspius vorax Barbus luteus
Liza abu Alburnus mossulensis Alburnus mossulensis
Plant species
Phragmites australis Phragmites australis Ceratophyllum demersum
Ceratophyllum demersum Ceratophyllum demersum Myriophyllum verticillatum
Salvinia natans Typha domingensis Phragmites australis
Lemna minor Panicum repens Schoenoplectus littoralis
Typha domingensis Schoenoplectus littoralis Potamogeton pectinatus
Note: Ranking of species is based on bird counts, fish sampling numbers per catch, and
percent cover on 100-meter line transects in each marsh.
a. Nonnative carp species introduced from Iran.
of bird species (45% of the number at Al-Hawizeh; figure 7).
The mean functional difference between Al-Hammar and the
natural area (averaged functional differences for all five in-
dicator functions, regardless of sign) was 40%, whereas the
mean functional difference for Suq Al-Shuyukh was only
23% (figure 7), indicating that Suq Al-Shuyukh was closest
to Al-Hawizeh in overall ecosystem function. The reflooded
Al-Hammar’s greater deviation from the natural site was due
mainly to higher salinity values (> 187%) from tidal influence,
and the community/habitat was apparently not as conducive
to bird recolonization, since this marsh had the lowest num-
ber of bird species (figures 6, 7). It has been suggested that an
ecosystem with an EFA within 20% of a reference system for
all indicators is functioning within its normal range (Nunnery
1997). Thus, the Suq Al-Shuyukh marsh is closest to match-
ing wetland functions in the remaining natural Al-Hawizeh.
Clearly, the Al-Hammar marsh is not as similar to the natural
site in functioning as Suq Al-Shuyukh, but there is no easy
way to assess whether this was historically the case or whether
it simply has not fully recovered.
These metrics, when scaled against historical values, indi-
cate that none of the remaining marshes were fully func-
tioning when compared with earlier measured ecosystem
levels (figure 7). It should be noted that the historic values we
used in our scaling were the weighted averages of the high-
est rates from a number of marsh studies done before drainage,
but we have no way of assessing the ex-
act locations of earlier studies in the
marshes. Indices of production func-
tions (plant production), decomposition/
redox status (oxygen status), and bio-
geochemistry functions (salinity) in all
current marshes were close to historic
values, except that salinity was higher
in Al-Hammar as a result of recent tidal
influences. Further measurements of
salinity in the lower Al- Hammar indi-
cated that current values there were close
to the historic averages of 1.7 ppt that
were measured when the tides were still
allowed to flow, before the destruction
of the marsh under Saddam Husseins
regime (Hussain 1992). This indicates
that this marsh has always been more
saline than other marsh areas because of
tidal influences. However, the number of
bird species (community/habitat func-
tion) and transparency depth (hydro-
logic function) were all much less (50%
to 60%) in the current marshes than
they were historically. This is not un-
expected, given the recent reflooding of
wetlands that had been drained for over
a decade.
Integrating the functional space for
each wetland (scaled total area covered
for five functions within each polygon shown on figure 7) gives
us a rudimentary way to assess the overall recovery of each
wetland ecosystem as weighed against historical values. The
natural Al-Hawizeh EFA is 60% of historic values, while the
reflooded Suq Al-Shuyukh and Al-Hammar reach 54% and
49% of historic levels after only two years of reflooding.
These findings suggest several interesting possibilities. First,
the natural Al-Hawizeh may itself be more damaged than has
been recognized and functioning only at two-thirds of historic
capacity, or it may not be a proper reference marsh to use for
comparisons because of differences in soil conditions and
water sources (Richardson et al. 2005). Second, the reflooded
marshes are on the road to restoration but, as expected, have
not reached full wetland functioning in less than two full
growing seasons. Of course, a better selection of indicators for
some functions (e.g., decomposition rate studies that are
now under way) may provide a better assessment of restora-
tion success in the future. The indications of a rise in salin-
ity over historic conditions and a decrease in depth of water
clarity in the reflooded marshes are matters of some concern.
We do not know whether these salinity and clarity trends will
continue, but if they do, they may affect overall restoration.
However, the fast recovery of plant production, overall good
water quality, and the rapid increases in most wetland
functions indicate that recovery of ecosystem function is well
under way.
486 BioScience • June 2006 / Vol. 56 No. 6
Figure 7. An ecosystem functional assessment (EFA) utilizing selected indicators of
five wetland functions: (1) production (Phragmites australis aboveground produc-
tion, in grams per square meter), (2) decomposition/redox status (milligrams of
oxygen per liter), (3) hydrologic function (water transparency, or depth of clear
water in centimeters), (4) biogeochemistry (salinity, measured as conductivity in
millisiemens per centimeter), and community/habitat (bird species number).
Figure shows an EFA comparison with the historical Al-Hawizeh values, scaled
to 100%, for the two restored marshes (Al-Hammar and Suq Al-Shuyukh) and the
remaining natural Al-Hawizeh, and a comparison of all marshes with reported
historical values from the 1970s and 1980s. Historical values are from Hussain
(1992) for water chemistry and oxygen, from Al-Hilli (1977) for macrophyte
production, and from Scott (1995) for birds.
Water availability in the future
Approximately 70% of the water entering Iraq comes from
river flow controlled by Turkey, Iran, and Syria (Partow
2001). Annual rainfall only averages around 10 cm in south-
ern Iraq, while evapotranspiration rates can reach nearly
200 cm (Buringh 1960). Groundwater sources are highly
saline and not useful for drinking or irrigation without ex-
pensive treatment (Buringh 1960). A series of major trans-
boundary water issues include the completion of the massive
Southeastern Anatolia Irrigation Project (GAP) in Turkey,
with 22 dams supplying irrigation water to 1.7 million
hectares (ha) of agricultural land, and the Tabqa Dam pro-
ject in Syria, supplying water to 345,000 ha of irrigated land
(Lorenz and Erickson 1999). In addition, the dike being
built by Iran to cut off the Iranian water supply to the Iraqi
portion of the Al-Hawizeh is nearing completion (Richard-
son et al. 2005). The water from the Iranian project report-
edly will be sold to Kuwait, which suffers severe freshwater
supply problems. The Atatürk Dam, built in Turkey as part
of GAP in 1998, can store more than the 30.7 billion cubic
meters (m
) of water that flows annually through the Eu-
phrates from Turkey into Iraq; this dam alone could almost
dry up the Euphrates (Partow 2001).
Projected future demands for water for agriculture and
other human uses are enormous, with estimates of Iraqs
water needs close to 95 billion m
by 2020; however, only 48
billion m
are estimated to be available after Turkey and Syria
complete their dams (Farhan 2005). Farhan (2005) also
estimates that to restore 10,000 km
of marshes will require
from 20 billion to 30 billion m
of water, nearly 50% of Iraq’s
available water after the completion of the water projects
and dams in Turkey and Syria (Partow 2001). It is clear from
these estimates that there will not be enough water to meet
the projected needs of Iraqs population and agriculture;
thus, the marshes will be in direct competition for water.
This will be especially true in drought years. However, some
of the used agricultural water may be adequate for use in the
marshes, but that has not been studied in terms of elevated
salinity and long-term nutrient and pesticide effects.
Given the competition for water among cities, agricul-
ture, and marshes, serious shortages will exist, especially in dry
years. Because the amount of water available for the marshes
may be severely restricted in some years, water should be di-
rected only into those former marshes with the most poten-
tial for maintenance of natural existing areas (e.g., Al-Hawizeh)
or for restoration of functional wetland ecosystems (e.g.,
Suq Al-Shuyukh). Other sites need to be chosen after com-
pletion of an ecological survey and soils assessment to pre-
vent the release of precious water into areas with lower
restoration potential.Another problem will arise when areas
that have been partially restored after water has been re-
leased into them have their water supplies cut off during
drought-year shortages. This will result in further destruction
of soil structure and overall loss of biota. To prevent this, a set
minimum yearly water allocation should be made to the
most viable former marsh areas. A working example of this
approach is the minimum water allocation designated for the
marshes in the Everglades to maintain ecosystem functions
under the recent Everglades restoration plan (Sklar et al.
2005). In Iraq, the Center for Restoration of Iraqi Marshes will
need to work closely with all the ministries, especially the Min-
istry of Water Resources and the Ministry of Agriculture, to
maintain future water supplies for the marshes. The wild
card in this plan is the Ministry of Oil, which has not actively
participated in the marsh restoration program; vast quanti-
ties of oil are reported to exist under former marsh areas in
southern Iraq.
Will Marsh Arabs return?
The question that is always asked is whether the Marsh Arabs
are returning to the marshes that have now been reflooded
(figure 1c, 3e, 3f). A recent survey done by USAID indicates
that not all of the Marsh Arabs want to return to live full-time
in the marshes (DAI 2004). The idyllic marsh life that has so
often been portrayed in the Western press is in reality a life
of poverty, disease, tribal wars, and, often, early death.
Nonetheless, some of the former Marsh Arabs do choose to
return to the marshes. On several trips we noted an increas-
ing number of families returning to Suq Al-Shuyukh and Al-
Hammar. When asked why they returned, they simply stated
that they had no other place to go and that the marsh pro-
vides some protection and food. However, the number of peo-
ple who have returned is probably under 10,000, and recent
estimates indicate that fewer than 10% of the remaining
Marsh Arabs may return because of the marshes’ poor fish-
ing and lack of clean drinking water, schools, and health
clinics. Moreover, many of the former Marsh Arabs are now
successfully farming on the edge of the marshes. For the first
time in their lives, many are making a meager living by farm-
ing wheat, rice, and barley (DAI 2004). When asked if they
want the marshes back for fishing and hunting, they answer
yes, but not if their farms and homes are flooded (DAI 2004).
Thus the future of the Marsh Arab culture is in jeopardy.
While some will return to their ancient life of buffalo
herding, fishing, and hunting, many will not—especially the
young. Those who do return will need to receive a long-term
commitment to sufficient water to sustain the restored marshes
and access to life’s basic amenities. When Marsh Arabs have
specific preferences for the areas they want to resettle, these
preferences should be among the criteria for selecting marsh
areas to be restored; however, these areas must also meet the
ecological conditions conducive for reestablishing wetland
functions if both ecosystem restoration and cultural reestab-
lishment are to be successful.
The restoration of southern Iraqs Mesopotamian marshes is
now a giant ecosystem-level experiment. Uncontrolled release
of water in many areas is resulting in the return of native plants
and animals, including rare and endangered species of birds,
mammals, and plants. The rate of restoration is remarkable,
considering that reflooding occurred only about two years ago.
Articles June 2006 / Vol. 56 No. 6 • BioScience 487
Although recovery is not so pronounced in some areas because
of elevated salinity and toxicity, many locations seem to be
functioning at levels close to those of the natural Al-Hawizeh
marsh, and even at historic levels in some areas. These
major questions remain to be answered:
Will water supplies needed for marsh restoration be avail-
able in the future, given the competition for water from
Turkey, Syria, and Iran, as well as competing water uses
within Iraq itself?
Can the Marsh Arab culture ever be reestablished in any
significant way in the restored marshes?
Can the landscape connectivity of the marshes be reestab-
lished to maintain species diversity?
What is clear is that water supply alone will not be suffi-
cient to fully restore all the marshes, and thus a goal of man-
agement should be to establish a series of marshes with
connected habitats (Theobald and Hobbs 2001) of sufficient
size to maintain a functioning wetland landscape. Iraq must
also use water more efficiently and cut waste if the country
is to have enough water to meet its future needs. For exam-
ple, the continued use of the ancient method of flooding
vast agricultural fields from open ditches, coupled with ex-
tremely high evapotranspiration rates, results in massive
losses of water to the atmosphere and increased soil salinity
problems (Buringh 1960). Modern drip irrigation approaches
used throughout other parts of the Middle East need to be em-
ployed to preserve Iraqs dwindling water supply.
Monitoring is continuing under USAID and international
funding to assess the recovery, and additional efforts are now
being focused on measuring plant and fish production,
changes in water quality, and specific populations of rare
and endangered species. Unfortunately, no research is under
way to assess how agriculture and the marshes can share
scarce water supplies, to identify toxic problem areas, to study
the problems of insecticide use by local fisherman, or to con-
duct a complete survey of the marshes to determine optimum
restoration sites, because of limited funding and increased vio-
lence in the area. However, the long-term future of the for-
mer Garden of Eden really depends on the willingness of
Iraqs government to commit sufficient water for marsh
restoration and to designate specific areas as national wetland
reserves. Political pressure from the international community
to maintain water supplies flowing into Iraq will also be crit-
ical to the restoration of the marshes.
Funding for this project was provided by the US Agency for
International Development, through the Iraq Marshlands
Restoration Program run by John Wilson and implemented
by Development Alternatives, Inc. (DAI), Bethesda, Maryland.
Many thanks go to Peter Reiss, who headed the DAI program
in Iraq, and Ali Farhan, who administers the marsh program
in Iraq. The Iraqi scientists and graduate students at the Uni-
versity of Basrah contributed data for aquatic plants, fisheries,
macroinvertebrates, and mollusks. Thanks to Ali DouAbul
of the Iraq Foundation and the Canadian International
Development Agency (CIDA) for providing salinity data on
Abu Zarag. Summary information on birds from CIDAs
Canadian–Iraq Marshlands Initiative project was provided by
Mudhafar Salmin. Barry Warner and the CIDA program
provided support for the Iraqi scientists to meet and discuss
these findings at the Montreal meeting of the Ecological So-
ciety of America. Many thanks go to CESifo Institute of Mu-
nich, Germany, for supporting C. J. R. during the writing
phase of this paper. Three anonymous reviewers provided
valuable comments during this article’s revision. Finally,
thanks to Mengchi Ho for help with statistics and graphics;
to Randy L. Neighbarger for technical editing; and to Hassan
Partow for helpful discussions and Landsat data on the areas
of marsh reflooding.
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Articles June 2006 / Vol. 56 No. 6 • BioScience 489
... Recognizing the importance of coastal wetlands, natural resource managers have used wetland restoration and construction to mitigate current and future losses (Erwin, 2009;Li et al., 2018;Pendleton et al., 2012;Richardson and Hussain, 2006;Warren et al., 2002;Wolters et al., 2005). The success of marsh construction and restoration efforts is variable, and is often viewed in part by whether success is measured by structural or functional recovery (Craft et al., 1999(Craft et al., , 2003He et al., 2016;Kleinhuizen and Mortazavi, 2018;Mitsch et al., 2013;Moreno-Mateos et al., 2012). ...
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Widespread degradation and destruction of coastal wetlands over the last century have spurred on the practice of creating salt marshes to mitigate losses of wetland area and ecosystem function. Constructed marshes can quickly recover plant biomass, but biogeochemical functions, such as the recovery of nitrogen removal capacity through denitrification, can take decades to centuries to recover. One potential mechanism for this uncoupling of structural and functional recovery is that an impaired microbial community subsequently impedes the nitrogen removal capacity of constructed marshes. While both bacteria and fungi can contribute to nitrogen removal via denitrification, little is known about fungal denitrification in wetlands, even though it has the potential to contribute to climate change via the production of the greenhouse gas nitrous oxide. Here, we measured fungal and bacterial denitrification potential rates and fungal biomass in sediments collected from a 33-year-old constructed marsh and a reference natural marsh to assess both a) the relative contribution of each group to total nitrogen removal and b) whether fungal biomass accrual is a driver of functional recovery in salt marshes. To assess the relative contributions of fungi and bacteria to denitrification, we added selective inhibitors (antifungal, antibacterial, or both) to sediments from each marsh and measured potential fungal and bacterial denitrification rates. We also measured sediment ergosterol concentrations seasonally as a proxy for fungal biomass. In the absence of inhibitors, denitrification potential rates in the constructed marsh were three times lower than in natural marsh sediment. Further, denitrification rates in the constructed marsh remained similarly low regardless of increasing inhibitor concentration, whereas denitrification rates in the natural marsh declined with increasing inhibitor concentration. When either inhibitor was added alone, denitrification was stimulated in the natural marsh, but was suppressed in the constructed marsh, suggesting an apparent competitive release, where the reduction of either bacterial or fungal competition for substrate thereby allowed the remaining competitor greater access to the substrate, in the natural marsh. We observed that compared to the constructed marsh, fungi in the natural marsh contributed ∼30% more (50% vs. 21%) to denitrification, and that fungal biomass was generally higher. Collectively, these data suggest that 3 decades post construction, denitrification rates and the contribution of fungal denitrification to total denitrification are lower in the constructed marsh than the natural marsh. These data also suggest that fungal biomass may limit the recovery of nitrogen removal in constructed marshes and that fungal denitrification can be an important pathway of N removal in salt marsh ecosystems.
... Fig. 2.1d shows the NDVI time series 1987-2019 for Qadisiyah River basin. The three regions (inside-Iraq, outside-Iraq, and total basin extent) have almost the same values before 1999, whereas from 1999 to 2019 the soil moisture values for inside-Iraq region have declined due to multiple drought events that have led the upstream countries of Euphrates river (i.e., Turkey and Syria) to decrease runoff of the Euphrates river into Iraq Richardson, 2009;Richardson and Hussain, 2006) by storing water in reservoirs. Fig. 2.2 represents the precipitation, air temperature, soil moisture, and NDVI over Mosul river basin. ...
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Study region: Middle East. Study focus: Droughts are a major natural disaster in almost every region of the world, causing negative impacts on natural resources and water basin management. However, it is challenging to study drought mechanisms in transboundary rivers where hydrometeorological observations are often not available or limited due to administrative issues. This study aims to assess drought conditions at three Iraqi transboundary river basins – (a) Mosul River Basin (between Iraq and Turkey), (b) Qadisiyah River Basin (between Iraq, Syria and Turkey), and (c) Dukan River Basin (between Iraq and Iran). The Famine Early Warning Systems Network Land Data Assimilation System (FLDAS) and satellite datasets have been used to calculate various drought indices and reservoir areas for the study period between 1987 and 2019. New hydrological insights for the regions: We exhibited the usefulness of FLDAS and satellite datasets in analyzing the variations and trends in hydro-meteorological variables and reservoirs surface areas over three transboundary river basins. Results exposed a significant drought exacerbation over the study regions during the periods of 1989–1991, 2000–2003, 2007–2012, and 2015–2018. Based on our analysis on drought duration and severity for inside- and outside- Iraq, we suggest the long-term meteorological drought indices (12-,24-month timescales) in monitoring drought conditions. Our results could be beneficial for water and natural resources managers in understanding spatial variability and impact of droughts.
... Generally, all Iraqi waters are classified as weak alkaline waters. Similar observations were made by other authors such as Richardson and Hussain (2006), and Mahmood (2008). ...
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Water, sediments, and aquatic macrophytes were collected from 13 fixed stations in February 2008: two stations at Hor Al-Hammar, two at Hor Al-Chibayish, eight at Hor Al-Huawiza, and one near Al-Sindebad Island at the junction of the Tigris and the Euphrates. Physical and chemical properties of water and sediments were studied as well as the concentrations of nutrients, which were variable in the different sites. Biodiversity was also investigated. A number of plant species collected there, was lower than that recorded by other authors due to the time of collection. Cover percent of each species was recorded in addition to biomasses which were also lower than those recorded formerly. Biomass of the emergent plants was the highest among other aquatic plants.
... Our results also have several health and environmental implications. The projected lower water flow from the Tigris and Euphrates rivers would threaten wetland ecosystems of Southern Iraq (Albarakat et al., 2018;Richardson & Hussain, 2006). Drying conditions over these wetlands and an emerging dust source located just to the south of Tigris-Euphrates headwaters (Nabavi et al., 2016) would potentially increase dust emissions and the associated risk of respiratory diseases locally and for the downwind countries like Iran (Khaniabadi et al., 2017). ...
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The Middle East is one of the world's most vulnerable areas to climate change, which has exacerbated environmental, agricultural, water conflict, and public health issues in the region. Here we analyze the latest climate model projections of precipitation and temperature for the very high emissions scenario, SSP5‐8.5, to detect potential future changes in this region. A baseline period (1981–2010) is compared with the middle (2040–2069) and end (2070–2099) of the 21st century. The results, representing the worst‐case scenario, identify the Tigris‐Euphrates headwaters as the hotspot of future compounding effects of climate change in the Middle East. Those effects result from the coincidence of elevated temperature, reduced precipitation, and enhanced interannual variability of precipitation. The hotspot overlays the location of the Southeastern Anatolia Project (in Turkish, Güneydoğu Anadolu Projesi [GAP]) irrigation initiative. In this climate context, risks to GAP viability and downstream water security, and associated potential for water‐related conflicts and migration are considerable and demand a reconsideration of the risk‐benefit assessment of GAP. This need has become more urgent after the recent widespread and deadly climate‐related conflicts and wildfires in summer 2021 across the Middle East that further underlined vulnerability of the region to climate extremes.
... Thus Hawizeh Marsh appears to be the stronghold of this and other rare and endangered species. It is also an important habitat for millions of wintering waterbirds (Richardson & Hussain, 2006), so its protection is of high priority. Although the Iraqi part of the marsh is within Mesopotamian Marshes National Park, it is threatened by falling water supply, intensive oil extraction on its shores, and increasingly intense heat waves (Al-Handal & Hu, 2015;Guarasci, 2015;Schär, 2016;Price, 2018), while in the Iranian part, an extra threat is multiple oil rigs and access roads being constructed directly within the marsh, as visible in the most recent update of Google Earth (2021). ...
... Generally, all Iraqi waters are classified as weak alkaline waters. Similar observations were made by other authors such as Richardson and Hussain (2006), and Mahmood (2008). ...
Full-text available
Water, sediments and aquatic macrophytes were collected from 13 fixed stations in February, 2008: two stations at Hor Al-Hammar, two at Hor Al-Chibayish, eight at Hor Al-Huawiza and one near Al-Sindebad Island at the junction of the Tigris and the Euphrates. Physical and chemical properties of water and sediments were studied as well as the concentrations of nutrients, which were variable in the different sites. Biodiversity was also investigated. A number of plant species collected there, was lower than that recorded by other authors due to the time of collection. Cover percent of each species was recorded in addition to biomasses which were also lower than those recorded formerly. Biomass of the emergent plants was the highest among other aquatic plants.
Full-text available
The Climate change is a global issue affecting different parts of our planet where we are living. However, the reasons of climate change and consequences differ at different parts too. In Iraq, including the Kurdistan Region, the reasons for the climate change are due to man-made and natural effects, where the rates of CO2 emission and those of other greenhouse gasses are increasing drastically, besides the global warming, decrease in the amount of water income in rivers and streams from Turkey and Iran, decrease of rain and snow fall, increase of population. All these have direct impact on the climate and accordingly the consequences are coming harsher and seriously effective on the daily life of the people. In this research, different man-made and natural effects, which directly affect the climate change are presented and described. Moreover, predictions and recommendations are given to decrease the consequences of the climate change in Iraq among them the status of awareness is one of the main reasons to climate change, besides the global warming. Abstract-The Climate change is a global issue affecting different parts of our planet where we are living. However, the reasons of climate change and consequences differ at different parts too. In Iraq, including the Kurdistan Region, the reasons for the climate change are due to man-made and natural effects, where the rates of CO 2 emission and those of other greenhouse gasses are increasing drastically, besides the global warming, decrease in the amount of water income in rivers and streams from Turkey and Iran, decrease of rain and snow fall, increase of population. All these have direct impact on the climate and accordingly the consequences are coming harsher and seriously effective on the daily life of the people. In this research, different man-made and natural effects, which directly affect the climate change are presented and described. Moreover, predictions and recommendations are given to decrease the consequences of the climate change in Iraq among them the status of awareness is one of the main reasons to climate change, besides the global warming.
This chapter establishes the foundation and rapid expansion of a private steel corporation in a frontier terrain leveraging both the relative security of Iraqi Kurdistan and the material destruction of the rest of Iraq as our ethnographic case study. It first describes the global shift in the steelmaking business from predominantly national and capital-intensive integrated steel mills that make steel from iron ore in a blast furnace into more flexible mini steel mills that melt scrap metal resources in electrified arc furnaces. The chapter then describes how scrap metal resources were ‘violently’ created in the region’s war cycles over the last three decades, transforming the landscape into a new frontier zone for the commercial capture of cheap and abundant scrap metal. Finally, it recounts how, in the context of a war economy and political fluctuations, nurturing a scrap metal yard emerges as one of the most essential tasks while operating on a frontier landscape.
Technical Report
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Fantastic Freshwater: 50 landmark species for conservation is a collaboration between more than 70 conservationists and 21 IUCN SSC Specialist Groups and Red List Authorities. It highlights wonder of - and threats to - freshwater wildlife, including five species from each of the major 10 taxonomic groups.
Large-scale wetland reforestation and hydrologic restoration projects have been implemented worldwide though few have been well studied or monitored following restoration. Many are located in the United States where laws require restoration to compensate for the loss of aquatic and wetland resources. Many projects are in coastal areas or deltas where the rate of wetland loss is great and where water and sediment are available to restore hydrology and build (wet)lands. Seven examples are presented: saline tidal marshes (2), inland freshwater marshes (2), delta wetlands (2), and mangrove reforestation (1). Techniques range from large-scale plantings to river diversions, and nearly all require reintroduction of hydrology. Large restoration projects often involve rewetting with river water (marshes of Mesopotamia (Iraq) and Yellow River Delta (China)), and/or sediment (Louisiana, United States). Perhaps the largest wetland restoration project in the world, the Florida Everglades, is a restoration in progress that may not be completed for another 60 years.
Kuwait's northern marine area is considered to be the receiving basin for the influx of sediments and associated pollutants from the Shatt Al-Arb estuary. In recent years, Iraq has undertaken to drain the southern marshes, which acted as a sink for the associated pollutants. This loss of marshes is expected to have far reaching consequences on the ecology of the northern Gulf. Bottom sediments from the area likely to be impacted by the draining of the marshes were studied for a variety of parameters. The results showed that petroleum-related pollutants (Ni, V, TPH, PAH and n-alkanes) were, generally, much higher in the southern part of the study area which may be due to the tanker traffic. Spotty higher levels of petroleum were encountered in the northern area, which were of recent origin and may have been the result of the draining of marshes. Chlorinated pesticides and PCBs were not detected in any of the samples. In general, there were indications of the negative impact of the draining of the marshes, however, long-term and more detailed studies are needed.
Some 43 taxa were revealed by enrichment culture techniques as opposed to 11 by direct microscopy. Microcoleus chthonoplastes and Nostoc muscorum were dominant in the field. The effects of temperature, N source, phosphate and NaCl were tested.-from Authors
Ecologists are familiar with two data structures commonly used to represent landscapes. Vector-based maps delineate land cover types as polygons, while raster lattices represent the landscape as a grid. Here we adopt a third lattice data structure, the graph. A graph represents a landscape as a set of nodes (e.g., habitat patches) connected to some degree by edges that join pairs of nodes functionally (e.g., via dispersal). Graph theory is well developed in other fields, including geography (transportation networks, routing applications, siting problems) and computer science (circuitry and network optimization). We present an overview of basic elements of graph theory as it might be applied to issues of connectivity in heterogeneous landscapes, focusing especially on applications of metapopulation theory in conservation biology. We develop a general set of analyses using a hypothetical landscape mosaic of habitat patches in a nonhabitat matrix. Our results suggest that a simple graph construct, the minimum spanning tree, can serve as a powerful guide to decisions about the relative importance of individual patches to overall landscape connectivity. We then apply this approach to an actual conservation scenario involving the threatened Mexican Spotted Owl (Strix occidentalis lucida). Simulations with an incidence-function metapopulation model suggest that population persistence can be maintained despite substantial losses of habitat area, so long as the minimum spanning tree is protected. We believe that graph theory has considerable promise for applications concerned with connectivity and ecological flows in general. Because the theory is already well developed in other disciplines, it might be brought to bear immediately on pressing ecological applications in conservation biology and landscape ecology.
It is now possible to formulate diagnostic selenium concentrations in four distinct ecosystem-level components; water, food-chain, predatory fish (consuming fish or invertebrate prey), and aquatic birds. Waterborne selenium concentrations of 2 µg/l or greater (parts per billion; total recoverable basis in 0.45 μ filtered samples) should be considered hazardous to the health and long-term survival of fish and wildlife populations due to the high potential for food-chain bioaccumulation, dietary toxicity, and reproductive effects. In some cases, ultra-trace amounts of dissolved and particulate organic selenium may lead to bioaccumulation and toxicity even when total waterborne concentrations are less than 1 µg/l. Food-chain organisms such as zooplankton, benthic invertebrates, and certain forage fishes can accumulate up to 30 µg/g dry weight selenium (some taxa up to 370 µg/g) with no apparent effect on survival or reproduction. However, the dietary toxicity threshold for fish and wildlife is only 3 µg/g; these food organisms would supply a toxic dose of selenium while being unaffected themselves. Because of this, food-chain organisms containing 3 µg/g (parts per million) dry weight or more should be viewed as potentially lethal to fish and aquatic birds that consume them. Biological effects thresholds (dry weight) for the health and reproductive success of freshwater and anadromous fish are: whole body=4 µg/g; skeletal muscle=8 µg/g; liver=12 µg/g; ovaries and eggs=10 µg/g. Effects thresholds for aquatic birds are: liver=10 µg/g; eggs=3 µg/g. The most precise way to evaluate potential reproductive impacts to adult fish and aquatic bird populations is to measure selenium concentrations in gravid ovaries and eggs. This single measure integrates waterborne and dietary exposure, and allows an evaluation based on the most sensitive biological endpoint. Resource managers and aquatic biologists should obtain measurements of selenium concentrations present in water, food-chain organisms, and fish and wildlife tissues in order to formulate a comprehensive and conclusive assessment of the overall selenium status and health of aquatic ecosystems.
Hypothetical models in the scientific literature sug- gest that ecosystem restoration and creation sites fol- low a smooth path of development (called a trajec- tory), rapidly matching natural reference sites (the target). Multi-million-dollar mitigation agreements have been based on the expectation that damages to habitat will be compensated within 5-10 years, and monitoring periods have been set accordingly. Our San Diego Bay study site, the Sweetwater Marsh Na- tional Wildlife Refuge, has one of the longest and most detailed records of habitat development at a mit- igation site: data on soil organic matter, soil nitrogen, plant growth, and plant canopies for up to 10 years from a 12-year-old site. High interannual variation and lack of directional changes indicate little chance that targets will be reached in the near future. Other papers perpetuate the trajectory model, despite data that corroborate our findings. After reviewing "trajec- tory models" and presenting our comprehensive data for the first time, we suggest alternative management and mitigation policies.