FORUM Limnological Research in the Swiss National Park Research has been conducted in the Swiss National Park for over 80 years. Botanists and zoologists have been particularly inter- ested in this area because of minimal human impact. It was not until the construction of hydroelectric power plants on the Spöl, creating the Lago di Livigno, that limnologists appeared on the scene. The current project is a “first” worldwide, where artificial flood events are being used in an attempt to revitalize the Spöl. The goal is to optimize the rest water regime and to restore the Spöl to its original condition as closely as possible. Streams and lakes in Switzerland are highly lated Spöl and for the two natural tribu- the construction of the hydroelectric power used and their natural flow regimes are taries, Ova Fuorn and Ova Cluozza. plants on the Spöl could not be prevented. altered to a large degree. Nature reserves It would have been up to the scientific are, therefore, especially important, both for Severe Impact: Construction community to investigate the ecology of studying natural processes and for assess- and Operation of the Spöl the Spöl before construction of the power ing background impacts of regional and Hydroelectic Power Plants plants and to establish a long-term moni- global environmental change (see box). The Despite strong opposition from environ- toring program; unfortunately, this was not Swiss National Park, established in 1914, mental organizations and the National Park, realized. Research at the time was limited has only gradually assumed the role of a reference area. Limnological Research Gained Scuol in Intensity after 1950 Lavin During the first few decades following establishment of the Park, limnological research was mostly limited to hydrobiol- Piz Pisoc ogists who investigated the algal communi- 3173 m ties of springs and streams [1]. Limnological M r a c è u n g i n research within the National Park increased Susch M S-charl l a V z Munt Baselgia a around 1950 with the onset of the planning r 2945 m o Mot Tavrü F 2420 m l a process for hyrdroelectric power plants on V the Spöl – water protection paradoxically Zernez being the trigger for more intensive limno- r h u Piz dal Fuorn c d V t s o F 2906 m t h a c Ova o l logical research even within the National l l B e a C l b Spin V a V l a t a u d S l Park. In 1952, a hydrobiological subcom- o Piz Terza l a N z a z d 2682 m V ü a l g a l V i mission was formed within the Science a z I o l F Commission of the National Park. After this u o m r n r a Munt la Schera e t Pass dal Fuorn t t 2587 m n e l point in time, extensive chemical/physical a l T a l V Buffalora Val Müstair a V investigations were conducted, resulting V a S-chanf s a s l a S d a l Tschierv in the compilation of an inventory of ap- l a V D Valchava i Piz Quattervals a Piz d’Esan v Piz dal Diavel Sta.Maria proximately 100 springs in the Fuorn area 3165 m e 3127 m l 3062 m a u n Müstair c h s and the determination of the water quality ü M l a of these springs [2]. Three hydrological V V a l T r u p gauging stations were established within c h u the Park in connection with the planning n process for the hydroelectric power plants. These gauging stations are still in operation today and provide runoff data for the regu- Map of the Swiss National Park. EAWAG news 54 30 FORUM P. Rey, HYDRA Rey, P. to a few sporadic measurements before construction and only a few checks during the construction phase between 1960 and 1970. However, scientists did succeed in gaining a relatively generous rest water regime for the Spöl, providing 35 Million m3 water per year. Even after the power plants started operations in 1970, research was limited to occasional studies (for example, a limnological study at the Livigno reservoir) and to checks on the biological condition of fisheries. Dynamic Flow Regime for the Spöl In 1990, the Engadin Power Plants released deep water from the Livigno reservoir, which provided an opportunity for scientific stud- ies covering a wide range of disciplines. These studies revealed that the section of the Spöl within the National Park below the dam had gradually turned into a series of pools with fairly stagnant water. This devel- opment did not appear to be prevented even by occasional flushing events and The heavily impacted Spöl under resiual flow conditions. draining of the reservoir. In addition, it was discovered that the smaller retaining reser- voirs within the National Park functionally p. 27). The purpose of these preliminary ex- The flooding experiments primarily use the turned into additional wastewater treatment periments is to optimize the environmental monitoring system which was installed in basins for the Upper Engadin since they benefit, i.e., to achieve the highest ecologi- 1996 and provide data for the heavily im- received water from the Inn. After extensive cal gain with the least amount of water [3]. pacted Spöl and the relatively pristine Ova discussions, the Science Commission for the National Park decided to revert this stream system, which is significantly im- Why and What Kind of Research in the National Park? pacted by sediment transport and deposi- Research gave the impetus for creating the National Park: a piece of pristine nature was to be tion, back to its original condition as far as protected from human activity to serve as a study object for natural processes. The National this is possible under the current condi- Park has, therefore, a research mandate in addition to the environmental preservation mandate, tions. The primary tool available for achiev- a charge that was passed to the Research Council of the National Park (currently called FoK- SNP) by the Swiss Academy of Sciences (SAS). ing this are artificial flood events. Due to good relationships between the board of Important research goals were and still are: Ⅲ Comprehensive inventory of “nature” within the Park directors for the EKW and the administration Ⅲ Observation of natural evolution or regeneration in the Park (long-term research, monitoring) of the Canton Grisons, the first flooding Ⅲ Comparison with utilized areas outside the Park (reference area) experiments were conducted in 2000. Until Ⅲ Recognition of interdependencies between ecosystems (ecosystem research) 2002, three annual high water events are Within this general framework, there are currently several interdisciplinary research foci: planned for the period between June and Ⅲ The future of the National Park in times of global climate change Ⅲ The importance of disturbances in ecosystem development August. These experimental floods are Ⅲ Hooved animals (Ungulates) in alpine habitats accompanied by interdisciplinary research, Ⅲ Interactions between society and the National Park with intensive collaboration by the Limnol- Further information under: www.nationalpark.ch ogy Department of EAWAG (see also article 31 EAWAG news 54 Fuorn. The monitoring efforts since 1996 these lakes, which is situated at an eleva- tative environmental and water protection. provide the baseline information against tion of 2500 m. The Limnology Department For the most part, we are dealing with ques- which the effects of the artificial flood of EAWAG will also participate in the devel- tions that can only be answered by long- events will be evaluated. To our knowledge, opment of this monitoring program. term investigations or monitoring programs. this is the first time such an experiment has In addition, preparations have been started With respect to the research in the National ever been conducted. The National Park for a systematic repetition of the measure- Park, we hope that EAWAG will continue provides an ideal setting for such an exper- ments conducted in the 1950s, where the the current engagement in limnological iment, since hydroelectric power generation water quality of springs was investigated. research in the Park and will contribute to and environmental protection are the only This is a first step in assessing to what de- understanding long-term processes. two interests that have to be considered. gree atmospheric changes, e.g., increased Initial results indicate that one or two small- nitrogen emissions, have an effect on water er flooding events per year, lasting one day below the ground. Another question will be, and providing flows of 10–30 m3/s, yield whether and how global warming affects significant environmental improvements. the overall moisture content of mountain Thomas Scheurer is executive We can only hope that artificial flooding ranges. director of the Research Council of the Swiss National Park events will soon be an integral part of rest (a council of the Swiss Academy water management in all of Switzerland. Opportunity National Park: of Sciences SAS). Reveal Long-term Processes Impulses from Acid Rain and As the example of the National Park demon- Global Climate Change strates, conflicts over water use and atmos- Apart from hydroelectric power plant opera- pheric impacts do not stop at the boundary tions, an additional impetus for limnological of nature reserves. Limnological research is [1] Nadig A. (1942): Hydrobiologische Untersuchungen in research was provided after approximately a crucial part of research in protected areas Quellen. Ergebnisse der wissenschaftlichen Untersu- 1970 by indications that atmospheric con- in at least two ways: first, long-term envi- chungen im Schweizerischen Nationalpark Zernez, 9. [2] Nold H., Schmassmann W. (1954): Chemische Unter- ditions are changing. Emerging evidence of ronmental changes impact aquatic eco- suchungen in der Ova da Val Ftur.