News
2015-11-09
A double line corridor between Arlon and Martelange : a high potential for LIFE Elia restoration
Passing by the N4 between Arlon and Martelange, impossible to miss the double line corridor. The two power lines with almost parallel paths are everywhere in the landscape.
When those lines cross forests, given the high security corridor widths and the distance between the two lines, the safety corridors measures over 100 m wide (125 m maximum).
This represents large areas (26 ha for this stretch) for Elia to maintain, beacause Elia must ensure management of these areas to avoid any electrical accident. These surfaces are interesting because they also offer the possibility of involving local farmers for ecological management of natural environment by grazing and mowing.
Safety standards are changing, landscapes evolve ...
The two power lines concerned are part of cross-border electricity connections. For some years now, the Elia company has implemented a security policy setting more drastic measures. This is reflected in particular by expanding the width of safe corridors to be sure that no trees can get in touch with the connectors.
In terms of the LIFE Elia actions, this implies a perfect synchronization between the fellings and restauration works which are made immediately after these fellings. The specifications for trees felling are drafted in close collaboration with the LIFE team.
Eventualy, the security of the electricity network is ensured, maintenance of vegetation is improved, biodiversity is promoted, the landscapes are embellished and local actors are involved ...a complete approach...
New tenants under overhead lines
When the terrain is too hilly and impossible to mow, the alternative vegetation management often consists of installing fences for cattle to graze.
Of course, this is an extensive grazing "green" respecting a set of very strict specifications to best reconcile the vegetation management and biodiversity. For example, the cattle breeder must manage the number of animals present per year depending on their age and the nutritional capacity of the place (Large Livestock Units).
Deux enclos ont été installés sur ce tracé, totalisant une surface de 6 ha. Un au niveau de la domaniale de Martelange, l'autre à proximité du lieu-dit « La Corne du bois des pendus ». Deux jeunes éleveurs motivés ont été désignés pour y faire pâturer des vaches rustiques du type Highland.
Two pens were installed on this site on a total area of 6 hectares. Two young farmers motivated were appointed there to graze Highland cows, a rustic breed.
Invasive plants : an ecological threat to local indegenous vegetation
The Black Cherry (Prunus serotina) is present throughout the Southern part of the country. For this invasive specie, native from North America, the power lines corridors are ideal propagation channels. Indeed, this species settles down very quickly on ground freshly exposed to light, such as a "classic" vegetation maintenance by rotary milling. After installing the plant, repetitive mulching of vegetation has no effect on the plant since the underground parts of the plant are never reached. These black cherry trees then become the dominant plant specie and smother indegenous vegetation
Beforehand LIFE Elia actions, we proceeded to the removal of seed trees located directly around the corridor to limit the supply of seeds.
Thereafter, all the actions have been designed to prevent the species to settle (herbaceous competition, dense forest edges plantation (11 ha in total)) or by installing regular maintenance preventing its development and therefore its fructification ; installing fences of a pasture (6 ha) or possible a mowing (7 ha).