Geoscience Reference
In-Depth Information
passive approach. Cleared coastal mangroves
may re-establish across tidal mudl ats once
human access to these areas is restricted. Float-
ing propagules from established mangroves in
the vicinity quickly colonize new areas by
anchoring themselves to open mudl ats. Allow-
ing rivers and streams to meander through
l oodplains during natural l ood stages by elimi-
nating controls on water l ows would help to
nourish riparian vegetation with the deposition
of silt and alluvial material.
More often, however, combinations of active
and passive methods or hybrid approaches are
used to achieve long-term restoration goals. An
example of this might include breaching a dike
or removing a dam that restricts natural water
l ows to allow for original hydrological condi-
tions to be re-established slowly. Once desired
hydrological l ows are established, l ora and
fauna are allowed to re-colonize with minimal
further inputs. The restoration of the southern
deltaic marshes of the Tigris and Euphrates
rivers of Iraq provides an example of such a
combined approach (United Nations Environ-
mental Programme 2010).
The Tigris and Euphrates l ow through the
Mesopotamian region of present-day Turkey,
Syria, Iran and Iraq. Both river systems have
been actively managed through the develop-
ment of irrigation canals or impoundments since
ancient times. Nearing the mouth of the two
rivers in the Persian Gulf, their waters distribute
across a wide area of shallow lakes, seasonally
inundated l oodplains and marshes, giving rise
to one of the largest and most important wetland
regions of the Middle East, also known as the
Mesopotamian Marshes (Fig. 13-7). Since the
1970s, these marshes have reduced dramatically
in size due to large-scale upstream impound-
ment and dam activities and the diversion of
their waters for irrigation in Turkey, Syria and
Iraq.
Additionally, during the 1980s and 1990s
Iraqi leader Saddam Hussein and his regime
persecuted political dissidents taking refuge in
the dense and tall Mesopotamian reed marshes,
and especially targeted the resident Ma'dan or
Marsh Arab communities (Scott 1995). As pun-
ishment, the regime built dikes and canals to
drain the wetlands and divert its waters, which
led to the almost complete elimination of the
southern marshes (Campbell 1999). Conse-
quently, the Ma'dan communities that lived
within these marsh systems for millennia lost
access to their ecosystem-dependent economic
livelihoods. Unable to i sh, or engage in reed
cultivation (
Phragmites australis
), harvesting or
agriculture, many moved out of the marshes to
seek refuge in other regions.
Recent conservation efforts since the end
of the Hussein era have breached dikes to re-
divert the Tigris and Euphrates waters into
the marshes. This re-l ooding strategy has
resulted in the quick and dramatic comeback
of substantial areas of wetlands, with the
associated re-establishment of i sh, bird and
macro-invertebrate communities (NASA 2010b).
Images from NASA's Moderate Resolution
Imaging Spectroradiometer (MODIS) sensor on
the Terra satellite show striking alterations to
the southern Iraqi marshes (Fig. 13-8). The
changes are clearly visible between the i rst
image from February 2002 at the height of the
wetland's drying out and the second from Feb-
ruary 2007, when re-l ooding efforts had made
signii cant strides in regenerating sections of
the marsh complex.
The February 2002 image indicates an almost
completely barren landscape in the midst of the
desert with a few patches of agricultural activity
seen along the sides of canals or fed through
irrigation systems. By the same month in 2007,
there are noticeable differences. Areas of vegeta-
tion have expanded considerably. Wet mud
patches and pools in dark shades, indicative of
re-l ooding efforts, can be seen across the center
of the image.
Restoring complex wetland functions and
processes is difi cult through breaching dikes
and re-l ooding efforts alone. Concerted l oral
and faunal restoration efforts in cooperation
with local resident communities such as the
Ma'dan would be required for their successful
re-establishment. Moreover, continued political
uncertainty and economic hardship within the
region complicate the tenuous nature of restora-
tion efforts, and the sustained long-term health
of these marshes remains in question.
