517
pollutants in inflow or the control of sources of pollutants in such a way as to restore
the quality of coastal water and sediment (Wilcox and Whillans 1999), whereas
biological restoration targets restoring the microorganisms, vegetation and fauna of
degraded wetlands. Vegetation studies provide insight into the effectiveness of
restoring wetland ecosystem functions. Although governments have put much effort
into coastal wetland protection practices, most wetland restoration projects focus on
the restoration and regulation of vegetation, and there is a lack of systematic studies
on the mechanisms of coastal wetland degradation and ecohydrological processes,
especially hydrological and biological connectivity on a large scale (Harttera and
Ryan 2010). Therefore, ecohydrological environmental indicators need to be further
integrated for successful evaluation of coastal wetland restoration based on the
holistic restoration of wetlands (Ellison 2000; Allen 2003).
An example of altered and partially restored coastal wetlands is the Danube
Delta in Romania (Fig. 17.1).
The total area of the Danube Delta Biosphere Reserve is approximately 5800 km
2
in Romania and more than 50 km
2
in Ukraine (Hanganu et al. 2002). In the Romanian
portion, the reserve includes the upstream Danube floodplain of Tulcea-Isaccea, the
Razim-Sinoe lagoon complex and the marine coastal waters (20 isobaths). The
Danube Delta itself refers to the area between the three main branches of the Danube
River (from north to south, these are the Chilia, the Sulina, and the Sfântu Gheorghe
(St. George) branches), which are located in Romania with a total area of 3510 km
2
.
The Danube Delta is the third largest delta in Europe, after the Volga Delta
(13,000 km
2
) and the Kuban Delta (4300 km
2
). The Danube Delta, Romania’s
youngest landmass, is a fluvial-maritime floodplain covering two floristic provinces, the lower Danube (ponto-sarmatic) and the Black Sea (euxinic) (Ciocârlan
1994). The diversified geomorphology, soils and hydrological conditions favor the
proliferation of a large number of aquatic, semi-desert and saline habitats.
Each habitat is part of a unique nature conservation network. The flora in the
Danube Delta Biosphere Reserve (both the Romanian and Ukrainian sectors) are
characteristic of a steppe bioregion with a temperate climate featuring almost 1400
species of vascular plants (Hanganu et al. 2002), of which five species (one subspecies) are endemic (0.51% of the total number).
A vegetation map of the delta produced by [66] shows 44 types of vegetation
grouped into eight categories in the Romanian delta and a significant part of the
Ukraine delta. These units consist of the following: flood plain forests, beach/sea
vegetation and dune vegetation, salt-tolerant vegetation, sandy steppe meadows,
river elevation meadows, dune forests, marsh vegetation and aquatic vegetation.
Natural marsh vegetation and aquatic vegetation are the most widespread in the
Danube Delta. Vegetation cover of this type occupies 398,676 ha within the delta, of
which 362,965 ha is in the Romanian section and 35,711 ha is in the Ukrainian section (Hanganu et al. 2002). Reed marshes, covering more than 220,000 ha, are by
far the Danube Delta’s dominant vegetation type. The dominant species is
Phragmites australis, which is usually accompanied by hydrophilous species such
as Typha angustifolia, Schoenoplectus lacustris, Sparganium erectum, and
Thelypteris palustris. Most of the plant communities and species are terrestrial, and
17 Alteration and Remediation of Coastal Wetland Ecosystems in the Danube Delta…
pollutants in inflow or the control of sources of pollutants in such a way as to restore
the quality of coastal water and sediment (Wilcox and Whillans 1999), whereas
biological restoration targets restoring the microorganisms, vegetation and fauna of
degraded wetlands. Vegetation studies provide insight into the effectiveness of
restoring wetland ecosystem functions. Although governments have put much effort
into coastal wetland protection practices, most wetland restoration projects focus on
the restoration and regulation of vegetation, and there is a lack of systematic studies
on the mechanisms of coastal wetland degradation and ecohydrological processes,
especially hydrological and biological connectivity on a large scale (Harttera and
Ryan 2010). Therefore, ecohydrological environmental indicators need to be further
integrated for successful evaluation of coastal wetland restoration based on the
holistic restoration of wetlands (Ellison 2000; Allen 2003).
An example of altered and partially restored coastal wetlands is the Danube
Delta in Romania (Fig. 17.1).
The total area of the Danube Delta Biosphere Reserve is approximately 5800 km
2
in Romania and more than 50 km
2
in Ukraine (Hanganu et al. 2002). In the Romanian
portion, the reserve includes the upstream Danube floodplain of Tulcea-Isaccea, the
Razim-Sinoe lagoon complex and the marine coastal waters (20 isobaths). The
Danube Delta itself refers to the area between the three main branches of the Danube
River (from north to south, these are the Chilia, the Sulina, and the Sfântu Gheorghe
(St. George) branches), which are located in Romania with a total area of 3510 km
2
.
The Danube Delta is the third largest delta in Europe, after the Volga Delta
(13,000 km
2
) and the Kuban Delta (4300 km
2
). The Danube Delta, Romania’s
youngest landmass, is a fluvial-maritime floodplain covering two floristic provinces, the lower Danube (ponto-sarmatic) and the Black Sea (euxinic) (Ciocârlan
1994). The diversified geomorphology, soils and hydrological conditions favor the
proliferation of a large number of aquatic, semi-desert and saline habitats.
Each habitat is part of a unique nature conservation network. The flora in the
Danube Delta Biosphere Reserve (both the Romanian and Ukrainian sectors) are
characteristic of a steppe bioregion with a temperate climate featuring almost 1400
species of vascular plants (Hanganu et al. 2002), of which five species (one subspecies) are endemic (0.51% of the total number).
A vegetation map of the delta produced by [66] shows 44 types of vegetation
grouped into eight categories in the Romanian delta and a significant part of the
Ukraine delta. These units consist of the following: flood plain forests, beach/sea
vegetation and dune vegetation, salt-tolerant vegetation, sandy steppe meadows,
river elevation meadows, dune forests, marsh vegetation and aquatic vegetation.
Natural marsh vegetation and aquatic vegetation are the most widespread in the
Danube Delta. Vegetation cover of this type occupies 398,676 ha within the delta, of
which 362,965 ha is in the Romanian section and 35,711 ha is in the Ukrainian section (Hanganu et al. 2002). Reed marshes, covering more than 220,000 ha, are by
far the Danube Delta’s dominant vegetation type. The dominant species is
Phragmites australis, which is usually accompanied by hydrophilous species such
as Typha angustifolia, Schoenoplectus lacustris, Sparganium erectum, and
Thelypteris palustris. Most of the plant communities and species are terrestrial, and
17 Alteration and Remediation of Coastal Wetland Ecosystems in the Danube Delta…