The reinstatement of degraded semi-arid and nutrient-poor grasslands
Semi-arid and nutrient-poor grasslands are very special types of grassland which can be found at locations that lack nutrients and are dry. In the eastern regions of Luxembourg there are large areas of such grassland that occur where Upper Trias and Middle Trias (shell-bearing limestone) strata prevail. As this land is relatively unproductive for agricultural purposes many of these semi-arid and nutrient-poor grasslands are no longer used and suffer scrub invasion, in turn leading to the decline of their extremely special and adapted biodiversity.
Semi-arid and nutrient-poor grasslands represent some of the most speciose biotopes in Europe!
Typical features of the landscape in the eastern regions of Luxembourg
In Luxembourg the semi-arid and nutrient-poor grasslands occur primarily in the east of the country on grey, undulating Upper Trias topographies, (for example in Junglinster or Niederanven) or on very thin chalky soils (often only a couple of centimetres thick) overlying the Middle Trias rocks to be found along the Moselle (between Mertert and Schengen) and in the valleys of its tributaries, for example in Manternach, Gostingen or Greiveldange. Typical occurrences of this grassland vegetation can be seen on south-facing slopes. Characteristic features of the soils are their lack of nutrients and an inability to store water. On hot summer days the soils can dry out to such an extent that wide fissures appear.
Juniper, a feature typical of such land in earlier times, is today a species under extreme threat on semi-arid and nutrient-poor grasslands!
Protected throughout Europe!
The ecological importance of semi-arid and nutrient-poor grassland is due to the particular flora and fauna that can be found there. Only a very few species of plants are able to survive under the extreme conditions on such land that offers little in terms of nutrients or water. Examples of such survivors are many of our various types of orchid as well as a few extremely rare species of insects and birds, such as the red-backed shrike (Lanius collurio) or the great grey shrike (Lanius excubitor excubitor). This pronounced concentration of rare species of flora and fauna is the reason that European-level protection is afforded to these semi-arid and nutrient-poor grasslands (the Habitats Directive).
The fate of many areas of semi-arid and nutrient-poor grassland: excessive scrub invasion reducing biodiversity
Appropriate use for agricultural purposes
These marginal-profit areas were formerly used for agricultural purposes. Cattle and sheep grazed on what sparse vegetation there was. When agricultural operations were intensified, farms were enlarged and the land was consolidated it became increasingly difficult to manage these marginal-profit locations. Many areas of nutrient-poor grassland were transformed into profitable grassland by the use of the chemical fertilizers that were increasingly applied around the middle of the 20th century. Other areas of nutrient-poor grassland, primarily those on hillsides, were abandoned completely for agricultural purposes. Both these developments (intensification and zero-use) have had disastrous effect on the ecological value of nutrient-poor grassland. Where such grassland is intensively cultivated the species which are typical of nutrient-poor grassland (such as orchids or common milkwort) are squeezed out by the more profitable species found on intensively managed grassland. Where nutrient-poor grassland is no longer used, it lies fallow and is invaded by scrub, which in turn leads to the disappearance of ecologically valuable flora and fauna. Either way, the result is the impoverishment of the ecosystems typical of the location. The agricultural use and management of the land must take account of the flora and fauna found there. The aim is to establish a pattern of agricultural use that best makes use of the sparse growth without damage to the biotope. There is also a need to keep a check on the growth of hedgerows. Nutrient-poor grassland supporting too much scrub is less able to offer a suitable environment for sustaining orchids, the great grey shrike or rare insects. Regular scrub clearance is needed at a number of locations.
The Great Grey Shrike (Lanius excubitor) is a raptor that is protected throughout Europe and is to be found mainly in protected areas of nutrient-poor or semi-arid grassland.
Protecting the areas of nutrient-poor and semi-arid grassland: join us!
natur&ëmwelt – Fondation Hëllef fir d'Natur has always included in its responsibilities the maintenance of nutrient-poor grassland. Many areas of nutrient-poor or semi-arid grassland have been purchased and are being professionally managed so that they do not fall victim to degradation and ultimately disappear. In order to buy more areas of nutrient-poor grassland and so ensure their long-term protection against degradation and disappearance the
natur&ëmwelt – Fondation Hëllef fir d'Natur needs your help! Your donation to the foundation will enable us to purchase additional areas of nutrient-poor grassland thereby ensuring that this biotope, which enjoys protection throughout Europe, is kept safe.
To prevent damage to orchids and other rare species agricultural use and management must be optimised!
The lizard orchid (Himantoglossum hircinum): a typical, albeit very rare, resident of nutrient-poor or semi-arid grassland.