PROJECT DESCRIPTION
BACKGROUND
In the past, open habitats such as raised bogs, transition bogs, heaths and grasslands covered a great part of the southern border region between France and Belgium. Many of these habitats and related species are now endangered in Belgium but are still present on the Plateau Croix Scaille, where the river La Houille and its tributary la Hulle take their source. The project area boasts an impressive 13 habitat types of Community interest, including the priority habitats bog woodland, Tilio-Acerion and alluvial forests, and Nardus grasslands.
However, some 50% of these two river valleys have been planted with exotic conifers in the past fifty years. As well as the direct destruction and fragmentation of semi-natural habitats, this has provoked increased flooding, erosion of riverbanks, reduced shelter for large wildlife and general loss of biodiversity. Many abandoned plots, in particular the bogs, are menaced by spontaneous reforestation and invasion by purple moorgrass (Molinia caerula).
In the previous two decades, the Réserves Naturelles RNOB and the Walloon Region had established some protected areas in the region. However, while carrying out extensive inventories, it became clear that more ambitious conservation and management actions were needed in the area if the rare habitats and species were to survive.
OBJECTIVES
The overall objective of the project was to improve the quality of the two river valleys, restoring open landscapes and enhancing the connectivity between the currently fragmented habitats. The project planned to restore habitats on three Natura 2000 sites that had been extensively planted with conifer groves.
RESULTS
The Cx SCAILLE project succeeded in restoring a significant area of natural and semi-natural heathland, peat bogs and wet meadows from exotic conifer plantations. It exceeded many of its quantitative objectives and demonstrated the success of targeted habitat restoration actions following tree removal.
The project purchased 113 ha of valley terrain for the establishment of nature reserves. This saw the protected reserves of the valley increase more than four-fold from the pre-project area of 35 ha. Most importantly, it improved the connectivity of the protected spaces by grouping protected pockets together and reducing the distance between them.
The beneficiary permanently removed exotic conifer plantations - mostly spruce - from 60 ha of public land and came to agreements with around 120 private landowners for the removal and sale of trees from 114 ha. The Municipality of Gedinne agreed to abandon plantation projects over a further 27 ha. Thus, a total of 201 ha was safeguarded for restoration into natural and semi-natural habitats.
Following the removal of trees, actions were carried out to restore 227 ha of meadows and heathland. Key activities were windrowing of the remnants from the tree felling on 90 ha, milling of remaining tree stumps over 62 ha and the removal of turf and raking up of the soil to eliminate accumulated mulch and encourage germination of seeds across 20 ha. The project demonstrated the benefits of such actions immediately following tree removal to prepare the ground for restoration.
On around 70 ha where conifer seedlings were encroaching into areas of hardwood forest or clearings, a technique of girdling was used - removing two rings of bark at 20 and 100 cm high - to kill the tree and create standing deadwood for xylophagous or caverniculous species such as many insects and woodpeckers.
To restore natural hydrology to the peat bogs, peaty heathlands and wet meadow habitats, the project filled in drains using clay plugs, built low stone barriers to prevent excessive drainage and dug out around 150 new ponds on the valley floors and in peaty areas. The first restorative mowing was conducted on wet meadows in the final year of the project with specially purchased machinery. Grazing cattle were introduced on 15 ha of fenced-off meadow.
The project benefitted from the organisation of conservation volunteering days on the project sites. An unexpected outcome of the project was the identification of a new threat to the site watercourses from the invasive Himalayan balsam and giant hogweed plant species. Field workers removed what they could from the rivers and streams. Better news was the discovery of clear signs of the presence of the otter (Lutra lutra) and beaver (Castor fiber), which are natural indicators of healthy river eco-systems.
Further information on the project can be found in the project's layman report and After-LIFE Conservation Plan (see "Read more" section).