Vorkommen der Kleinen Teichrose Nuphar pumila und des Hybrids N. x intermedia in der Schweiz

Abstract

Kozlowski G. and Eggenberg S. 2005. Distribution of the least water-lily (Nuphar pumila) and the hybrid N. x intermedia in Switzerland. Bot. Helv. 115: 125-136.The least water-lily (N. pumila (TIMM.) DC) is very rare and endangered in Switzerland and Central Europe. To provide a basis for its conservation, we present a distribution map with all natural, re-introduced and extinct populations in Switzerland. Only four natural populations of N. pumila still exist in Switzerland: Lac de Lussy and Lac des Joncs (FR), Gräppelensee (SG), and Kämmoosteich (ZH). These populations and their sites (lakes) are described, and the co-occurring plant species are listed. Results suggest that the populations from Kämmoosteich and Lac de Lussy are affected by hybridisation and competition with N. lutea. In these two lakes, the hybrid N. x intermedia was very abundant. The presence of N. lutea and N. intermedia in Kämmoosteich and Lac de Lussy should be regarded as one of the most serious threats of pure N. pumila populations. To facilitate further investigation and conservation field work, a detailed morphological description of the two taxons is presented and illustrated by original drawings. To escape extinction in Switzerland, N. pumila needs further appropriate action plans for all natural and newly re-introduced sites as well as an improved knowledge of its genetic structure and habitat preferences.Key words: Conservation biology, distribution map, endangered plant species, hybridisation, Nupharetum pumili, Nympheaceae. EinleitungWährend des letzten Jahrhunderts hat sich unsere Landschaft in vielen Regionen stark verändert; damit wurde auch die Pflanzenwelt erheblich beeinträchtigt. Besonders bedroht sind Arten feuchter Standorte, deren natürliche Lebensgrundlagen durch Entwässerung, Torfausgrabungen und Intensivierung der Landwirtschaft weitgehend 1 Published in "Botanica Helvetica 115(2): 125 -136, 2005" which should be cited to refer to this work.

Hybridization as a threat in climate relict Nuphar pumila (Nymphaeaceae)

“…Several recent studies outlined the rapid decay of this species, with almost 20 stations that went extinct in Switzerland over the last century following human-mediated landscape alterations (Kozlowski and Eggenberg 2005). Consistent with these observations, our survey reveals alarmingly low diversity Fig.…”

“…Together with N. microphylla from North America it belongs to socalled Nuphar-dwarfs since they are much smaller in size and number of floral parts than the most common species N. lutea (Heslop-Harrison 1955;Meusel et al 1965;Padgett 1998Padgett , 2007. Most information on N. pumila in the Alps and surrounding area could be found in the publications of Kozlowski and Eggenberg (2005); Roweck and Reinöhl (1986);and Roweck (1988). Finally, the papers of Heslop-Harrison (1953, 1955 on the genus Nuphar in Great Britain, although published more than half a century ago, remain valuable.…”

“…Importantly, three populations (JON, GRA and HAL) occurred in ponds and lakes of high altitude; where the presence of N. lutea-a lowland species-has never been attested. Those three populations have been used as reservoirs of ''pure N. pumila'' genotypes for recent ex situ collections and re-introduction campaigns (Kozlowski and Eggenberg 2005) and were considered as the N. pumila reference pool in our analyses. Collections were made in 2014 at the height of the growing season (June/August).…”

Aquatic vegetation as an indicator of littoral habitats and various stages of lake aging in north-eastern Poland

“…Roelofs (1986a, 1986b) and Heegaard et al (2001) demonstrated that the phytocoenoses of M. spicatum have a broad ecological amplitude with respect to properties of water, and developed best in waters relatively rich in SO 4 2x . Our results also confirm the distinct character of the habitats of some floating-leaved plant communities, particularly the phytocoenoses of N. pumila, which are found in mostly nutrient-rich (Roweck, 1988;Kozlowski and Eggenberg, 2005) soft waters, poor in Ca 2+ (Kadono, 1982;Roweck, 1988;Kłosowski and Tomaszewicz, 1990;Doll, 1991). The results obtained by some authors confirm our findings for N. lutea (waters rich in Ca 2+ and NO 3 x -Wiegleb, 1978; hard alkaline watersDe Roelofs, 1986a, 1986b;Smits et al, 1988), N. candida (mesotrophic or slightly eutrophic waters Pietsch, 1982; narrow ecological amplitude with respect to Ca 2+ - Van der Velde et al, 1986) and P. amphibium (waters relatively poor in NH 4 + - Wiegleb, 1978).…”

“…In some phytosociological works, the relationship of C. demersum to organic substrates was also demonstrated (e.g., Doll, 1991), and in the case of N. alba confirmed by Rejewski (1981). Roweck (1988) and Kozlowski and Eggenberg (2005) indicated that the phytocoenoses of N. pumila were confined to organic substrates. The data obtained by other authors (e.g., Roelofs, 1986a, 1986b;Van Katwijk and Roelofs, 1988) show that the phytocoenoses dominated by species such as P. natans, P. lucens, N. lutea, M. spicatum and M. verticillatum have a wide ecological amplitude with respect to substrate properties.…”