Ménez Du quarry (Finistère), France — Study and maintenance of a plot in order to contribute to better knowledge of a mesophili...Context
The Imerys Group operates in the “Ménez Du” quarry for its kaolin. It is located in the Monts d’Arrée area, south of Morlaix in Brittany in the village of Loqueffret.
The site is part of the Armorique Regional Nature Park. In addition, it has be labeled a ZNIEFF type 2 zone for its outstanding ecological wealth. The mesophilic moorland is particularly protected in this region with 2 species: Sphagnum pylaisi and Drosera rotundifolia. Both of these carnivorous plats are rare in France. The environments conducive to their growth are very wet, acidic zones such as moorlands or peatlands.
In the various studies done in line with the quarry’s opening, the major impact related to the clearing of part of the moor. However, the zones of greatest ecological interest were listed in the authorized, non-mined area.
Several types of measures were taken to develop and diversify the Monts d’Arrée moorland:
- Cooperation for the entire duration of operations with local farmers to enhance unmined areas by mowing or controlled grazing.
- Plot D446, identified as high ecological potential, is being studied in cooperation with FCBE* and other local partners. The aim of the study is to determine plant associations as the land evolves and identify favorable parameters for the development of some rare species. Since 2001, the moor’s evolution has been monitored on this plot. To do so, 4 m² experimental plots have been partly or wholly cleared.
- At the end of operations, the aim will be to restore soil conducive to moorland, taking into account the observations made on the studied D446 plot. Land will be restored to similar conditions to the original in terms of nature and topography.
The monitoring work by AQUATERRA tracks the evolution of plot D446. In 2002 and 2004, inventories of rare species were drawn up on some experimental plots.
The site was remarkably colonized by the round-leaved sundew, Drosera rotundiflora. This initially absent species spread over the plot’s uncovered sunny ground. On zones where the moor grew denser, the study showed the plant’s disappearance. This is therefore a pioneer species that colonizes depleted environments.
Other species such as royal fern and sphagnum were occasionally observed on the site. They have special protection status.
An inventory will be taken on the rehabilitated zones to verify this new substitute environment.
- Recommandation on management of plot D446 by Fédération Centre-Bretagne Environnement (FCBE)
- Monitoring operation by AQUATERRA