Search results for "Nymphaea"
showing 6 items of 6 documents
Revision of Nymphaea candida range – new data on the distribution and habitat preferences of the species in south Poland
2010
The paper presents results of geobotanical and taxonomic studies on the distribution and habitat requirements of Nymphaea candida in southern Poland. The researches were conducted in southern Poland in 2003-2009, in the provinces of Lower Silesia, Lublin, Małopolska, Opole, Silesian province as well as, in southern parts of Mazowieckie and Lubuskie. Flowers, leaves and fruits of Nymphaea species were collected from 27 locations. Altogether pollens from 73 populations of N. candida and 18 of N. alba from all the researched area were measured. The trophic level of an ecosystem was evaluated according to the results of the total nitrogen, total phosphorus, chlorophyll a, transparency and biolo…
Revision of Nymphaea candida range - New DATA on the distribution and habitat preferences of the species in Southern Poland
2011
The paper presents results of geobotanical and taxonomic studies on the distribution and habitat requirements of <em>Nymphaea candida</em> in southern Poland. The researches were conducted in southern Poland in 2003-2009, in the provinces of Lower Silesia, Lublin, Małopolska, Opole, Silesian province as well as, in southern parts of Mazowieckie and Lubuskie. Flowers, leaves and fruits of <em>Nymphaea</em> species were collected from 27 locations. Altogether pollens from 73 populations of <em>N. candida</em> and 18 of <em>N. alba</em> from all the researched area were measured. The trophic level of an ecosystem was evaluated according to the re…
Response of the aquatic plants and mollusc communities in Lake Kojle (central Europe) to climatic changes between 250 BCE and 1550 CE
2018
Abstract Sediments of Lake Kojle, located in the transition zone between the nemoral and boreal biogeographic zones in NE Poland, were analysed to verify the response of the aquatic ecosystem to major environmental changes. High-resolution plant macrofossil, mollusc and pollen data were derived from two replicate parallel cores and revealed several shifts in the biota composition within the littoral zone between 250 BCE and 1550 CE. The reaction of the aquatic ecosystem to temperature changes was found to be minor, which is ascribed to the mitigating influence of water and the wide ecological tolerance of most of the taxa. Najas marina, considered as an indicator of warmer conditions, was t…
Breeding system and pollination of Nuphar luteum (L.) Smith (Nymphaeaceae) in Norway
1995
Summary Insects visiting Nuphar luteum in southern Norway were caught and identified and their role as pollinators was evaluated by observations of their behaviour. Nuphar luteum is mainly pollinated by Apis mellifera and Bombus spp. Moreover syrphid flies are efficient pollinators. The chrysomelid beetle Donacia crassipes , although sometimes present, plays but a minor role as pollinator. By bagging and emasculating flowers the breeding system was shown to be one of mixed mating. Nuphar luteum is protogynous and primarily cross-pollinated, but because male and female stages overlap during the second day of flowering, and because it is self-compatible, self-fertilization is possible. Agamos…
Do female leaf beetles Galerucella nymphaeae choose their mates and does it matter?
1998
The role of active female choice in sexual selection is frequently difficult to ascertain, and this is particularly the case for many insect species. Also, it is uncertain whether choosing between males would affect offspring viability. We designed an experiment to investigate the presence of female choice in a Coleoptera species (Galerucella nymphaeae). We also estimated whether mate choice would have any effect on offspring performance. Females were first placed with two males in a test arena to see which of the males copulated with the virgin female, and how quickly. Subsequently the loser male was offered a new virgin female to test for any change in latency time until mating. The two-m…
Egg and larval load assessment and its influence on oviposition behaviour of the leaf beetle Galerucella nymphaeae
1993
The oviposition behaviour of the water-lily beetle Galerucella nymphaeae was examined. This species is a specialist herbivore on the floating leaves of nymphaeids Nymphaeaceae and especially on the yellow water-lily, Nuphar lutea. Females lay their eggs in clutches on the leaves, and after hatching, the larvae feed on the leaves. The quality of the leaves decreases quickly after the larvae hatch, and eventually the leaves will sink below the water surface, whereupon the eggs, 1st-instar larvae and pupae are killed by drowning. The influence of conspecific eggs, larvae and feeding tracks on the oviposition preferences of the beetles was tested. Females were allowed to choose between fresh le…