Particularly valuable habitats
Alluvial zones, mires and dry meadows and pastures were still very widespread around 1850. Since then, they have come under considerable pressure from the correction and engineering of water courses, drainage and the intensification of agriculture. Due to their rarity and characteristic species, which in some cases only arise in these habitats, these particularly valuable habitats require strict protection and, in some cases, revitalisation, regeneration and upgrading measures today.
Between 1900 and 2010 the area of alluvial zones declined by 36 percent, that of mires by 82 percent and that of the dry meadows and pastures by 95 percent. In addition, alluvial zones and mires had already declined significantly in area in the 19th century – a development that is not represented here. Switzerland only has small residues of these once widespread and valuable habitats. They have been placed under protection since 1987 (mires), 1992 (alluvial zones) and 2010 (dry meadows and pastures) and it has been possible to stem the quantitative areal losses. However, decreases in quality through nitrogen inputs, changes in the water supply and other impacts continue in some cases.
- Related indicators
- Areas designated for biodiversity
The reconstruction of the former area of the alluvial zones, mires and dry meadows and pastures is based on a digital evaluation of historical maps (Siegfried maps) from around1900 (alluvial zones, mires) and model calculations and archival information (dry meadows and pastures). The area recorded around 2010 was determined with the help of the federal inventories and the evaluation of current maps.