Remote European mountain lake ecosystems: regionalisation and ecological status

Abstract

1. A survey of c. 350 remote high altitude and high latitude lakes from 12 different mountain regions across Europe was undertaken to explore ecosystem variability, climate forcing, environmental conditions and pollution threats at a scale not previously attempted. 2. Lakes were sampled for a range of contemporary and sub-fossil organisms including planktonic crustaceans, rotifers, littoral invertebrates, chironomids, diatoms and cladocerans. Survey and cartographic data were used to determine environmental characteristics at each site. Organic pollutants and trace metal concentrations were measured in the lake sediment. 3. A number of separate studies were undertaken which examined the environmental characteristics of the surveyed lakes (climate forcing and chemical composition), distribution of biota relative to local, regional and biogeographical factors and pollution threats (acidification, heavy metals and persistent organic pollutants) to these sensitive ecosystems. 4. There is a strong regional element to the way that environmental factors combine (including climate and pollution threats) and the biota responds in mountain lakes across Europe. From a management perspective it is clear that lake classification and the development of useful typologies and assessments of reference conditions should be undertaken at regional rather than pan-European scales. 5. There are some common features across lake districts related to the timing of industrialisation, but the studies carried out on metals, organic pollutants and nitrate deposition indicate that each lake district has distinct pollution threats. Climate warming already affects most of the lake districts and there are considerable uncertainties as to how this will modify conditions in remote European mountain systems. 6. The lake district concept goes beyond a geographical construct and merits further theoretical and experimental development as an ecological concept.

Limnological changes in South Carpathian glacier-formed lakes (Retezat Mountains, Romania) during the Late Glacial and the Holocene: A synthesis

“…Magyari et al, 2009a) and larger scale projects (e.g. Catalan et al, 2009;Heiri et al, 2014) started. Within the multiproxy paleoecological project PROLONG (Magyari et al, 2009a) several biotic and abiotic proxies have been studied on sediment cores of four mountain lakes including sediment organic matter (as loss on ignition) and biogenic silica content, geochemical element concentrations, diatoms, chrysophycean cysts, cladocera, ostracods and chironomids (Korponai et al, 2011;Braun et al, 2012;Buczkó et al, 2012;Iepure et al, 2012;Tóth et al, 2012;Buczkó et al, 2013;Soróczki-Pintér et al, 2014;Tóth et al, 2015).…”

Evidence of exotic trout mediated minnow invasion in Pyrenean high mountain lakes

“…2,400 m and are relatively small and deep (average surface area of 2 ha and average maximum depth of 17 m, with the largest of 54 ha and deepest 105 m). Due to their common origin, there is a close positive relationship between surface area and maximum depth (Catalan et al 2009). Most of the lakes are above the tree line with catchments partially covered by meadows, although some of them are within or below the tree line.…”

Aquatic beetles of the alpine lakes: diversity, ecology and small-scale population genetics

“…The proper understanding of, e.g., climate-driven processes on a pan-European, or even larger geographical scale is impossible without detailed knowledge of the local fauna and its ecological patterns within the particular mountain regions. It is also recommended to classify and assess the reference conditions of the lakes on regional scales for conservation and management purposes (Catalan et al, 2009). However, in most hydrobiological studies of alpine lakes, water beetles have been expressed as a negligible part of the macrozoobenthos in comparison with other, more numerous and diverse taxonomic groups (e.g.…”