Why cutting the spruces?|
In the 19th century, the spruce has been introduced at large scale into the Eifel
as the "Prussian tree". Actually, it is not indigenous here. Its extended occurrence
near the water has an important impact on the indigenous living communities: Its needles
cannot substitute the litter being essential as food base for numerous inhabitants of
the brook. As a consequence, indigenous living communities become poor and are replaced.
Besides, spruce forests are migration barriers for terrestrial insects and other animal
species, and they prevent the exchange of individuals between the habitats. Also
micro-organisms, naturally contributing to the purification of the brook, are absent,
as well as microhabitats as aquatic moss pads. In places, the needle litter leads to a
continuous acidification. Last, but not least, the spruce forests shadow the soil, the
brook and the sources during the whole year, which can result in a lowered mean annual
Spruces are not indigenous in the Eifel.
Along the upper course of the Rur and the Perlenbach, there are still spruce forests up
to the brook at large scale.
In the source region of the brook "Kyll", the percentage of spruces in the floodplain
is only about 5 %. By the LIFE-project "Living brooks in the Eifel", about 70 ha of the
spruces near the water shall be transformed into riparian forests or wet and nutrient-poor
grassland typical for floodplains.
Opposite to the spruce, the black alder is a typical tree species of riparian and swamp
forests; the floodplain is its natural habitat. The alder litter is the main food source
for numerous inhabitants of the brook. Its extensively branched root system stabilizes the
banks in a natural way and offers refuges to fishes and other brook animals. On its roots,
there live a lot of micro-organisms, contributing to the purification of the brook.
The black alder - a multi-functional miracle.
Why is the free circulation of flowing water important?
Not only salmons, but also smaller fish species and cyclostomes like the bullhead
(Cottus gobio) or the brook lamprey have to migrate to get to their spawning grounds
or to their winter and summer habitats. However, a lot of brooks are blocked up by
migration barriers (e.g. dams, plunges and tubes). Already small plunges of 20 cm are
inconvincible barriers for small fishes and invertebrates. Therefore, the restoration
of the free water circulation is an important goal of our project.
The river trout seeks oxygen-rich gravel banks for spawning.
In the three project areas, the migration of the brook inhabitants is hindered by 80
barriers in total (e.g. dams, tubes, ponds on the brook). In the Perlenbach, ponds on
the brook separate the upper valleys of seven tributaries from the main valley where
there is a dam. Additionally, about 85 % of the Perlenbach tributaries are separated
from the main brook by tubes. In the area of the Rur brook, there are four dams with a
differing barrier effect. Besides, several tributaries are split or separated from the
Rur brook by ponds on the brook or by tubes. Also in the Kyll brook, the free circulation
is interrupted by three ponds on the brook and tubes in almost every tributary. It is
the goal of the project to remove all migration barriers and to replace them by bridges
of different construction.
Plunges of 20 cm height are already inconvincible barriers for small fishes
Tubes are replaced by so-called special steel profiles open towards the river bed.
Restoration of the natural water dynamic
By the rectification of the brook and the consolidation of the brook bed and the
banks with concrete slabs, ripraps or other material, valuable habitats in the brook
are lost. Natural brook structures like undercut banks or the cavity system of the
brook bed are absent in consolidated parts of the brook. However, those structures
are indispensable for the indigenous brook inhabitants.
Artificial bank and brook bed pavements are removed.
Natural brook course
In the Perlenbach, the consolidation of the brook is limited to some tributaries
and some parts of the main valley just above the mouth into the Rur brook. In the
Rur area, such consolidations are only present in the Schwarzbach and in small sections
of the main brook. These are mainly bank consolidations where strong lateral erosion
threatens the banks. For the Kyll brook, this threat is hardly relevant.
The present consolidations shall be removed, so the brook can develop once again
its own dynamics. Diverse structures like cutbanks and slip-off banks, plunging
pools and gravel banks can develop once again.
The water quality is charged by nutrients from agricultural cultivation.
The nutrients are applied to the field as mineral or organic fertilizer (slurry).
If more nutrients are applied then the plants can absorb, a surplus of nutrients
arises. These nutrients are washed out and the water is eutrophicated.
Species-rich spignel meadow
By extensifying (reducing the agricultural production) the agricultural used
lots in the project area, the immission of nutrients into the brooks which
naturally are extremely nutrient-poor shall be minimized. This includes the
creation of fallow strips along the water offering a very effective protection
against diffuse immissions.
In the whole project area, the agricultural use of the floodplain lots is already
extensive. Within the scope of the project, this surface shall still be extended
by the districts' programme for the cultural landscape.
What is the negative effect of increased fine sediment immissions?
The cavity system of the brook bed (interstitial) is the most important habitat
for numerous water insects and the juveniles of the pearl mussel. Also fishes or
cyclostomes like the brook trout (Salmo trutta) or the brook lamprey (Lampetra planeri)
need an open cavity system for spawning or as a habitat for their larvae. Obviously,
the blocking of the interstitial by fine sediments is an important reason for the
absence of young pearl mussels in the Perlenbach. Also negative effects on the fish
species spawning in gravel banks are probable. Besides, a strong clouding of the
water is a stress factor in general for all aquatic organisms which should not be
Arable land and vegetation free surfaces, unconsolidated fords and strong erosion are
the mean sources of fine sediments. In the Perlenbach, the main part of the fine
sediments origins from the Belgian military training area Elsenborn. There are large
vegetation-free firebreaks and several unconsolidated fords used by heavy vehicles.
The training area is situated outside the project area; therefore it is not possible
to carry out project measures in this zone. In agreement with the base administration
the sediment emissions shall be reduced in a distinct and sustainable way. Thus, the
problem areas are recorded and the first sedimentation basins have been built below
fire lanes. Additionally, a stronger consolidation of ten fords, a careful maintenance
of the route ditches and a sensibilization of the military staff are planned. In the
further course of the Perlenbach and in the areas of Rur and Kyll, there are smaller,
dispersed fine sediment sources, mostly unconsolidated fords and smaller bank sections
without vegetation and with intense lateral erosion. Here and there, increased fine
sediment emissions occur after clearings or the sporadic use of a quarry in the
Especially after heavy rains, the fine sediment load of the brooks becomes visible.
Overview of measures in LIFE-nature-project
"Lively streams in the Eifel
(1. Oktober 2003 bis 31. August 2009)
Nr./Name Measures in accordance with the LIFE-proposal Finished measures
A.1: Charting of biotop-types Charting of different areas Completely finished
A.2: Check-Ups - flora & vegetation
- Makrozoobenthos incl.
- stream-birds - flora & vegetation
- Makrozoobenthos incl.
Crayfishes and freshwater
- stream birds
A.3: Detailled management-plans Landcare and development plans fort he project-areas, Detailled-management plans
for building-measures Completely finished
A.4: Applying for water-right-approvals Applying for measures-approvals Completely finished
B.1: Buying of ponds and buying of land for carrying out the measures 3 ponds
2,8 ha spruce forests 3 ponds
2,8 ha spruce forests
B.2: Compensation of earlier clearing forests For about 18 ha compensation-payment
for 16,1 ha compensation-payment have been payed
B.3: Extensive using of ponds Clearing up-work Completely finished
C.1: Initial planting of cleared grounds About 14 ha initial-planting about 19,4 ha initial-planting
C.2: Later landcare - about 49 ha elimination of young spruce trees
- about 21 ha landcare of measuresd - about 48,5 ha elimination of young spruce trees
- about 29,1 ha landcare of
C.3: Riverside lengths about 8 km about 11,8 km
C.4: Planting the banks with local trees about 13 km about 17,5 km
C.5: Disposal of water barriers and borders - 73 tubes
- 14 borders
- 10 ponds
Total: 97 - 76 tubes
- 19 borders
- 11 ponds
C.6: Elimination of borders und buildings belong the streams about 3 km about 4,3 km
C.7: Rebuilding of "Furten" replacement for often used "Furten" by bridges - rebuilding of 7 Furten
- replacement by bridges:4 - rebuilding of 12 Furten
- replacement by bridges:4-
C.8: Rebuilding of ponds near the stream-systems - 19 ponds - 18 ponds
C.9: Removal and reducing of pollutes not fixed Completely finished
C.10: transformation of spruce-forests - 39 ha private
- 31 ha public
total: 70 ha elimination of spruce forests
- 38,9 ha private
- 38,7 ha public
total: 77,6 ha elimination of spruce forests
and local 14,4 ha
D.1: Extensive using of measures
Not fixed 41,6 ha extensive using of measures
D.2: Landcare of the river sides Not fixed Completely finished
D.3: Consultation of fishers Not fixed Completely finished
E.1: Information-papers Information-Flyer 3 editions
E.2: Internet-presentation www.life-baeche.de
E.3: information-events Not fixed 134 information-events
E.4: Publishings Not fixed 9 publishings and a lot of press-texts
E.5: Conference 2-days Conference - 2-days conference
E.6: Film-documentation Poject-film Project-film
E.7: Exhibitiong 3 mobile exhibitions Exhibition would be finished as a bigger one for used in different locations
E.8: Report for normal people Report in three languages Report in 2 languages
E.9: Local informations - temporary local information signs for measures
- information signs
- Rur-hiking path with information paper - temporary local information signs for measures
- 3 information signs
- Rur-hiking path with information paper -
F.1: project-personal Completely finished
F.2: first equipment Completely finished
F.3: Fortbildung nicht festgelegt Completely finished
F.4: monitoring - water-quality
- flora & vegetation
- makrozoobenthos crayfishes
- stream-birds - water-quality
- - flora & vegetation
- Makrozoobenthos incl.
Crayfishes and freshwater
- stream birds
Carrying out the project :
Biological station in the government of Euskirchen e.V. (project-leader)
Biological station in the government of Aachen e.V. (project-partner)
Project-manager: Stephan Miseré
Project-personal: Bettina Krebs, Karin Wagner, Ursula Franke, Bianca Eulner