Approaches to Swiss mire monitoring
Following a referendum in 1987, the Swiss Federal Government introduced regulations that set strict terms and targets for the protection and rehabilitation of mires. Three national inventories have been established, each designating sites o f national importance embracing 550 bogs, 1200 fens and 90 mire landscapes. It is now the duty of the 26 Swiss cantons to implement compulsory mire conservation measures in order to obey the federal law, which states that mires of outstanding beauty and national importance are to be preserved in their entirety. Where feasible, regeneration operations should be implemented on mires already suffering disturbance. According to this legislation mire protection in Switzerland comprises both quantitative and qualitative aspects and, consequently, the size of mire sites of national importance must not be reduced and their diversity with respect to structure, types, vegetation, and species richness has to be maintained or improved. There are different ways to achieve the protection required by legislation and there is an on-going discussion about the best way to reach both the legislation targets and a general acceptance by landowners and users. Considering the high cost of public and private efforts involved in the national mire conservation scheme it is important to detect advantages and disadvantages of the different implementation procedures as early as possible. A step-wise procedure has been recommended to achieve this, starting with evaluation of the implementation of the regulations and measures by the cantons and ending up with monitoring of their effects on mire habitats. Therefore, in 1993, the Advisory Service for Mire Conservation was commissioned by the Federal Office of Environment, Forests and Landscape to develop a sensitive nationwide long-term mire monitoring strategy in order to reveal discrepancies between targets and reality. It was also directed to provide scientific results that would enable the authorities to evaluate and revise their protection policies. The basic problem of any nature conservation monitoring scheme is to answer the following questions: "How is it possible to get precise information from vague estimates?" and "Which is the most efficient method to detect changes in space and time?" Thus, to develop a successful monitoring approach it is absolutely vital to set clear objectives, have an appropriate sampling design and conduct a professional baseline assessment of the target sites. The Advisory Service for Mire Conservation has developed and tested several methods to assess both the quantitative and qualitative aspects o f mire change. The pilot survey of "Gross Moos" in Schwändital (canton of Glaris) is presented as an example.