Threats and attacks

Like the European bogs, it is estimated that about 50% of peatlands in France were destroyed.
Those that have been preserved nevertheless suffered many degradations.

Extraction of peat

extraction de tourbeThe extraction of peat in the traditional way (and sometimes industrial) was systematized in the Jura (18th - early 20th century). It concerned especially the raised bogs and was often conducted in the form of disbursement spans, penetrating more or less deeply into the bog from its margins. If water is not retained downstream, peating pits behave as drains, while the extraction zones themselves show no recovery in turfigenesis.

Impact on habitats and species

Peat being exported, the extraction is a direct habitat destruction. In addition, this type of pit negatively impacts the surrounding bog habitats (7110, 7120, 7150 and 91DO). Furthermore, the bottom of the pit is most often colonized by agregations of degradations habitats, no peat producing and birch base.



Plantation forestry

plantation sylvicoleIn an attempt to economically develop these "unproductive" areas, some peatlands were planted with spruce during the second half of the 20th century. This practice has often been coupled with drainage work.


Impact on habitats and species

The planting of conifers causes the disappearance of the open areas related communities (ie d. Most heritage species bogs). Similarly, samples increased evapotranspiration and interception phenomenon leads to a decline in the water table and surface moisture. The consequences are similar to drainage.


Presence of infrastructures disturbing the functionning of the sites

Several infrastructure are presents on the Natura 2000 sites and disrupt the functioning of the peatlands:

  1. "Bog of Cerneux-Gourinots (...)": a asphalt platform infringes upon a raised bog;
  2. "Bogs and lakes of Chapelle-des-Bois (...)" a drinking water pipeline is going through the bog. Simultaneously, a drainage ditch was created to allow maintenance;
  3. "Entrecôte du Milieu": a forest track crosses the bog throughout.



For the sake of economic development, almost all of the Jura peatlands suffered drainage work. A drain causes a hydrological disturbance by lowering the water level. In bogs, this reduction causes also soil disturbance manifested by a compaction of the peat decreasing porosity and water holding capacity.

Impact on habitats and species

With drying, habitats will change and stop producing peat. We are witnessing the growth or proliferation of common species such as purple moor grass and birch. Furthermore, the mineralization of the peat causes the release of fertile elements leading to an increase of the trophic level.

Habitats and specific species of peatland ecosystems (including Sphagnum) hygrophile and usually heliophilous oligotrophic, can no longer be maintained under the new conditions.


Rectification of streams

rectification d un cours d eauLow areas of the Jura peat complexes are often crossed by naturally meandering streams. In undisturbed situation, the average level of the river is close to the level of full board, the accompanying table in the bog remains at a high rating. However, some of these streams have undergone rectification, generating a new rectilinear bed wider and deeper than the original.

In addition to the destruction of aquatic habitats itself, effects on the surrounding peatland are disastrous. The stream, then, acts as a drain. The oversized bed decreases greatly overflows, thus limiting groundwater recharge. Finally, the corrected bed creates the acceleration of flow velocities increasing the erosion and the sinking of the river bed

Impact on habitats and species

The effects are similar to those described for drainage. They concern all peatland habitats covered by the program, except for bog communities (7110, 7120, 7150 and 91DO), which are not, except in cases, crossed by rivers.