5.2 Restoration of Mangroves
Mangrove forest restoration often focuses on restoring the environmental conditions
as planting of mangrove tree species often fails. Combining planting with increasing
the water quality by measurements elsewhere (e.g. erosion prevention in river delta’s
or limiting nearby aquaculture) has more effect. The best practise to restore mangrove systems, however, is to create entirely new habitats. This is very costly and
hard to achieve over large areas, but as the necessity for resilient and durable coastal
protection grows, mangroves restoration may present a good option for the longterm (Lewis III et al. 2005).
5.3 Restoration Projects of Saltmarshes and Tidal Flats
The Wadden Sea at the coasts of the Netherlands, Germany and Denmark is the
largest tidal flat system in the world. These three countries therefore have an
important international responsibility to protect these habitats. A large part of this
area belongs to national parks and most habitat types are additionally protected by
the European Habitats Directive and additional (national) regulations. However,
despite regulations and measures for nature protection the Wadden Sea is highly
impacted by waste, pollution and eutrophication, dumping of dredge spoil, shipping,
fishery, residential and commercial development, energy production (oil and gas
extraction, wind parks), coastal defence measures, tourism, and diverse other anthropogenic influences (e.g. Tougaard and Ovesen 1981; Goetting et al. 1988; Hobohm
1992, 1993; Lasserre 1994; Hughes and Paramor 2004; Kirwan and Megonigal
2013; Gu et al. 2018). Many pollutants and debris wash ashore after it has been
lost by ships. For example, in 2019, the cargo vessel MSC Zoe lost over 200 transport
containers in the North Sea near the German coast. Within days, the beaches of the
Wadden isles were covered with chemicals, micro plastics and plastic pallets which
are likely to enter the food web of the dunes. Additionally, on the long-term land
subsidence, insufficient sediment supply and the rising sea level may impact parts of
the Wadden Sea (Baptist et al. 2019).
For the Wadden Sea saltmarshes, the following five targets have been formulated
in the trilateral Wadden Sea plan of The Netherlands, Germany and Denmark
(Esselink et al. 2017):
1. maintaining the full range of variety of saltmarshes typical for the Wadden Sea
landscape;
2. achieving an increased area of saltmarshes with natural dynamics;
3. achieving an increased natural morphology and dynamics, including natural
drainage of mainland saltmarshes, under the condition that the present surface
area is not reduced;
4. maintaining a saltmarsh vegetation diversity reflecting the geomorphological
conditions of the habitat with variation in vegetation structure;
Coastal Habitats, Shallow Seas and Inland Saline Steppes: Ecology,. . .
297
Mangrove forest restoration often focuses on restoring the environmental conditions
as planting of mangrove tree species often fails. Combining planting with increasing
the water quality by measurements elsewhere (e.g. erosion prevention in river delta’s
or limiting nearby aquaculture) has more effect. The best practise to restore mangrove systems, however, is to create entirely new habitats. This is very costly and
hard to achieve over large areas, but as the necessity for resilient and durable coastal
protection grows, mangroves restoration may present a good option for the longterm (Lewis III et al. 2005).
5.3 Restoration Projects of Saltmarshes and Tidal Flats
The Wadden Sea at the coasts of the Netherlands, Germany and Denmark is the
largest tidal flat system in the world. These three countries therefore have an
important international responsibility to protect these habitats. A large part of this
area belongs to national parks and most habitat types are additionally protected by
the European Habitats Directive and additional (national) regulations. However,
despite regulations and measures for nature protection the Wadden Sea is highly
impacted by waste, pollution and eutrophication, dumping of dredge spoil, shipping,
fishery, residential and commercial development, energy production (oil and gas
extraction, wind parks), coastal defence measures, tourism, and diverse other anthropogenic influences (e.g. Tougaard and Ovesen 1981; Goetting et al. 1988; Hobohm
1992, 1993; Lasserre 1994; Hughes and Paramor 2004; Kirwan and Megonigal
2013; Gu et al. 2018). Many pollutants and debris wash ashore after it has been
lost by ships. For example, in 2019, the cargo vessel MSC Zoe lost over 200 transport
containers in the North Sea near the German coast. Within days, the beaches of the
Wadden isles were covered with chemicals, micro plastics and plastic pallets which
are likely to enter the food web of the dunes. Additionally, on the long-term land
subsidence, insufficient sediment supply and the rising sea level may impact parts of
the Wadden Sea (Baptist et al. 2019).
For the Wadden Sea saltmarshes, the following five targets have been formulated
in the trilateral Wadden Sea plan of The Netherlands, Germany and Denmark
(Esselink et al. 2017):
1. maintaining the full range of variety of saltmarshes typical for the Wadden Sea
landscape;
2. achieving an increased area of saltmarshes with natural dynamics;
3. achieving an increased natural morphology and dynamics, including natural
drainage of mainland saltmarshes, under the condition that the present surface
area is not reduced;
4. maintaining a saltmarsh vegetation diversity reflecting the geomorphological
conditions of the habitat with variation in vegetation structure;
Coastal Habitats, Shallow Seas and Inland Saline Steppes: Ecology,. . .
297