Projects
The Runde watercourse in the Netherlands is a part of the corridor between the `Dollard` and `Bargerveen`
Natura 2000 sites. The main authorities and governmental organizations in the Runde project will participate in promoting measures to reconstruct and revitalize the former watercourse in a more natural way.
• In the `Waveney/Little Ouse` initiative the quality of the ecological corridor will be improved by implementing six
projects along two rivers between the counties of Norfolk and Suffolk in England. Here 19 governmental and nongovernmental organizations are participating in a variety of wetland restoration projects for new reedbeds and open
water from former intensive agricultural land and derelict meadow, improved wet grassland management and enhancement of some of the water courses. Stepping stones are being built to connect Natura 2000 sites.
• In Groningen, Overijssel (the Netherlands) and Nidersachsen (Germany), based on the analysis of a GISdatabase, implementation plans are being drawn up for different kinds of ecological corridors. In Overijssel a plan is
being prepared to connect two important wetland areas, the Wieden and the Weerribben.
ECOLOGICAL NETWORKS
•
Atlantic salmon (Salmo salar)
The Atlantic salmon is listed in the EU Habitat Directive and in the Bern Convention. Indirectly the species receives
protection via the EU Water Framework Directive, which aims for the improvement of water quality. It has a NorthAtlantic distribution that ranges from Portugal to the Arctic Circle. It includes rivers in Spain, France, the UK, Ireland,
Norway, Sweden and Finland. The salmon spawn in areas located in the upstream tributaries of large rivers. The
species migrates to the sea, returning after some years to its spawning area to reproduce and die. The spawning will
only take place in areas with clean water with high oxygen levels and moderate currents.
Civil engineering structures such as dams, weirs and culverts form an obstacle for migration to the upstream located
spawning areas and changes in river morphology have resulted in the gradual degradation of juvenile and spawning
habitat.
A combination of measures are required to restore the landscape connectivity for the Atlantic salmon. These measures comprise the improvement of water quality, the bypassing of obstructions such as dams, weirs and culverts, the
restoration of spawning areas by restoration of the morphology of rivers and streams, and in some cases young fish
have been reintroduced in tributaries of big rivers. If the rivers are improved then other threatened species such as
Sea lamprey, Sturgeon, Barbel, Trout, Allis shad, Twaite shad and European bullhead will benefit.
in FRESHWATER ECOSYSTEMS
Working together
for a sustainable
future
YellowYellow-legged Dragonfly (Gomphus flavipes)
The Yellow-legged dragonfly is found in the lower sections of large rivers
in Western Europe, and is more common in Eastern Europe. The preferred habitat is formed by shallow braided river stretches with low current velocity. The larvae live in sand or between fine particulate matter
on the river bottom. The development from egg to adult lasts about three
years so that habitat conditions can not change too much over such a
period. The species was rather common in Western Europe, but it has
now become restricted to a few populations along the Loire and the Allier and a few rivers in Eastern Germany.
The Yellow-legged dragonfly is included in the EU Habitats Directive and
the Bern Convention. The reasons for its decline are likely to be a combination of water pollution and a loss of habitat
by canalization of rivers and streams and changed management of the water edges.
The habitat connectivity for the species may be enhanced by the improvement of water quality and the creation of
larval and adult habitats in nature development programmes. Additional species to benefit from such corridors are
within groups such as clams, mussels and snails, earthworms, beetles and midges.
This brochure was produced as part of the SEENET programme. For more information
please contact us at [email protected] or visit www.seenet.info
ECNC © 2007 Written and compiled by: Dzintra Ailte, Lawrence Jones-Walters,
Agnes Bruszik , Ana Nieto and Hanneke Wijnja.
Photographs: Bernd Kunz, Saxifraga Foundation, ECNC
References
Van der Sluis, T., Bloemmen, M., Bouwma I. M. (2004) European Corridors: Strategies for
Corridor Development for Target Species. ECNC, Tilburg, The Netherlands & Alterra
Bennett A. F. (2003) Linkages in The Landscape: The Role of Corridors and Connectivity
in Wildlife Conservation. IUCN, Gland, Switzerland
www.ten-project.org
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Why are ecological networks important?
Measures for the sustainable management of freshwater systems
Natural areas provide vital goods and services for people and make a significant contribution to human well-being. In
the European continent there are several million kilometres of flowing waters and more than a million lakes. Freshwater provides an important resource for the human population and is used for a variety of purposes: drinking, irrigation and industry, commercial fisheries, transport, recreation
(sports such as sailing, swimming, diving, skating and fishing and tourism activities like rafting and canoeing) and protection of natural areas. For many species rivers, lakes and wetlands are important natural ecological corridors for migration, dispersal or regular movement.
Many water bodies are useful in providing ecosystem services that
avoid, for instance, flooding of domestic property and industrial installations, natural water treatment, such as reedbeds, etc.
The following recommendations for water management activities for maintaining water bodies as ecological networks may be country or region specific, which emphasises the need for active planning. At a basic level the required
action may simply be a question of restoring water flows or reducing the impact of unseasonal flooding. Key actions
may include:
•
Active planning by key stakeholders such as developers, agencies,
planners land owners and water engineers (including at the very
local level of, for instance, individual farms), including:
- identification of areas of interest and value to wildlife and which
provide ecosystem services;
- avoidance of, mitigation and compensation for impacts to these;
- incorporation of measures for their management and maintenance;
- selection of areas for the creation of wildlife habitat and areas
which could provide ecosystem services;
- maintaining traditional extensive agriculture.
•
Sensitive management and maintenance of existing ditches,
streams, rivers and their associated features, including:
- avoiding major physical changes;
- temporal phasing of work to allow sections of water bodies to remain untouched;
- carrying out work at times that avoid wildlife, for instance, during
the winter months;
- restoration of meandering channels;
- recreation of features;
- bank modification to allow the reestablishment of aquatic plants
and animals along channelized sections of rivers and their
tributaries;
- restoration of water quality.
•
Construction of fish ladders at weirs and dams to enable fish migration.
•
Restoration and creation of reedbeds and replanting of floodplain
woodlands.
•
Restoration of natural processes such as winter flooding of floodplain grasslands (also as a method of providing flood relief downstream).
•
Leaving buffer strips of unharvested trees along water bodies .
•
Creation of new water bodies such as ponds and lakes (where this
does not damage existing habitat of value to wildlife)
•
Building of resting or nesting islands in fish ponds for birds.
Most freshwaters in Europe have been greatly influenced by human
intervention. The natural course of rivers and lakes has been changed,
the levees have been reinforced to form roads, dikes, and swamps and
the floodplain forests associated with rivers have largely disappeared.
The presence of flood control embankments, dams, weirs, barriers and drainage ditches not only disadvantages the
hydrological condition of the water bodies, modifies the water flow and decreases ground water levels, but also decreases the diversity of habitats and organisms. In addition, water quality has been severely reduced and the plant
and animal species that require clean water have vanished in many places.
Major activities affecting freshwater systems:
Activities
Actions
Impacts
Catchment
land-use
change
Afforestation and deforestation
Urbanization
Agricultural development and intensification
Land drainage/flood protection
Corridor engineering
Removal of riparian vegetation
Flow regulation – e.g. dams, etc
Channelization
Dredging and mining
- enhanced growth of phytoplankton, filamentous algae, or larger plants;
- increased nutrient and organic matter loading;
- degradation of aquatic and wetland ecosystems;
- reduction of habitat and species numbers and
diversity.
Instream impacts
Organic and inorganic pollution
Thermal pollution
Abstraction
Navigation
Exploitation of native species
Introduction of alien species
Ecological networks are one of the well recognized
tools to mitigate the impact of the human activities.
Ecological networks connect areas of habitat and allow animals
and plants to move through the countryside. This movement may
be an important factor in assisting the survival of many species in
relation to changes in land use and climate. As well as being vital
for the functioning of ecosystems, ecological networks and corridors, greenways and landscape linkages can also have aesthetic
value and contribute to an attractive living and working environment. They have important recreational and tourism value and
can provide further economic benefit by protecting property and
businesses from environmental impacts.
Policy relevance
The development of ecological networks and corridors is recognized as an
effective policy instrument for promoting nature conservation both at the
European and global levels. The following policy instruments acknowledge
the importance of enhancing connectivity at Pan-European level:
• The Pan-European Biological and Landscape Diversity Strategy (PEBLDS,
1995) calls for the conservation of biodiversity in Europe by promoting the
establishment and the maintenance of a Pan–European Ecological Network (PEEN). Among other ecological systems PEBLDS includes a chapter on actions regarding running waters and riparian wetlands.
• The Habitats Directive (1992) and the Birds Directive (1979) acknowledges
the importance of habitat connectivity.
• Ramsar Convention (1971) has adopted the vision to develop and maintain
an international network of wetlands.
• The Water Framework Directive (2000) contributes to ecological networks
by requiring long-term protection of available water resources.