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Anne Jäkäläniemi - One of the best experts on this subject based on the ideXlab platform.
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Local genetic population structure in an Endangered Plant Species, Silene tatarica (Caryophyllaceae)
Heredity, 2005Co-Authors: N. Tero, Jouni Aspi, Pirkko Siikamäki, Anne JäkäläniemiAbstract:Genetic substructuring in Plant populations may evolve as a consequence of sampling events that occur when the population is founded or regenerated, or if gene dispersal by pollen and seeds is restricted within a population . Silene tatarica is an Endangered, perennial Plant Species growing along periodically disturbed riverbanks in northern Finland. We investigated the mechanism behind the microspatial genetic structure of S. tatarica in four subpopulations using amplified fragment length polymorphism markers. Spatial autocorrelation revealed clear spatial genetic structure in each subpopulation, even though the pattern diminished in older subpopulations. Parentage analysis in an isolated island subpopulation indicated a very low level of selfing and avoidance of breeding between close relatives. The mean estimated pollen dispersal distance (24.10 m; SD=10.5) was significantly longer and the mean seed dispersal distance (9.07 m; SD=9.23) was considerably shorter than the mean distance between the individuals (19.20 m; SD=13.80). The estimated indirect and direct estimates of neighbourhood sizes in this subpopulation were very similar, 32.1 and 37.6, respectively. Our results suggested that the local spatial genetic structure in S. tatarica was attributed merely to the isolation-by-distance process rather than founder effect, and despite free pollen movement across population, restricted seed dispersal maintains local genetic structure in this Species.
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Local genetic population structure in an Endangered Plant Species, Silene tatarica (Caryophyllaceae).
Heredity, 2005Co-Authors: N. Tero, Jouni Aspi, Pirkko Siikamäki, Anne JäkäläniemiAbstract:Local genetic population structure in an Endangered Plant Species, Silene tatarica (Caryophyllaceae)
Christoph Reisch - One of the best experts on this subject based on the ideXlab platform.
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Population size and land use affect the genetic variation and performance of the Endangered Plant Species Dianthus seguieri ssp. glaber
Conservation Genetics, 2016Co-Authors: Verena Busch, Christoph ReischAbstract:Human activity and land use changes in the past decades have led to landscape homogenization and small-scale fragmentation of grassland habitats in most regions of central Europe. As a result, populations of many grassland Species are small and strongly fragmented, facing extinction due to genetic depauperation and local maladaptation in remnant habitats. In this study, remaining populations of the strongly Endangered grassland Species Dianthus seguieri ssp. glaber (“Ragged Pink”) in Bavaria were investigated in order to evaluate the environmental factors influencing its genetic variation and performance. We first evaluated habitat, vegetation and population structure. Species performance was then studied by assessing the number of generative shoots, flowers and fertile capsules; and evaluating seed weight and seed viability. Finally, genetic variation was analyzed using molecular markers (AFLPs). Our analyses revealed that population size and land use abandonment have the strongest impact on genetic variation and Species’ performance. Large and extended populations were most variable. 72 % of overall genetic variability of Dianthus seguieri ssp. glaber was found to be within populations, whereas 28 % remained between populations. Increased vegetation height and coverage, and a high proportion of gramineous Species resulting from the lack of land use, reduced genetic variation, effective fruit and seed set. Our study shows that both population size and land use abandonment need to be considered to ensure the long term protection of Endangered Plant Species. Maintaining an open habitat structure and adequate soil nutrient conditions through targeted annual mowing regime, over-storey vegetation trimming and green waste removal and the establishment of vegetation buffer strips will allow this Species’ persistence and continuous recruitment.
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Living in isolation – population structure, reproduction, and genetic variation of the Endangered Plant Species Dianthus gratianopolitanus (Cheddar pink)
Ecology and evolution, 2015Co-Authors: Christina M. Putz, Christoph Schmid, Christoph ReischAbstract:The Endangered Plant Species Dianthus gratianopolitanus exhibits a highly fragmented distribution range comprising many isolated populations. Based upon this pattern of distribution, we selected a study region in Switzerland with a lower magnitude of isolation (Swiss Jura) and another study region in Germany with a higher degree of isolation (Franconian Jura). In each region, we chose ten populations to analyze population structure, reproduction, and genetic variation in a comparative approach. Therefore, we determined population density, cushion size, and cushion density to analyze population structure, investigated reproductive traits, including number of flowers, capsules, and germination rate, and analyzed amplified fragment length polymorphisms to study genetic variation. Population and cushion density were credibly higher in German than in Swiss populations, whereas reproductive traits and genetic variation within populations were similar in both study regions. However, genetic variation among populations and isolation by distance were stronger in Germany than in Switzerland. Generally, cushion size and density as well as flower and capsule production increased with population size and density, whereas genetic variation decreased with population density. In contrast to our assumptions, we observed denser populations and cushions in the region with the higher magnitude of isolation, whereas reproductive traits and genetic variation within populations were comparable in both regions. This corroborates the assumption that stronger isolation must not necessarily result in the loss of fitness and genetic variation. Furthermore, it supports our conclusion that the protection of strongly isolated populations contributes essentially to the conservation of a Species' full evolutionary potential.
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living in isolation population structure reproduction and genetic variation of the Endangered Plant Species dianthus gratianopolitanus cheddar pink
Ecology and Evolution, 2015Co-Authors: Christina Putz, Christoph Schmid, Christoph ReischAbstract:The Endangered Plant Species Dianthus gratianopolitanus exhibits a highly fragmented distribution range comprising many isolated populations. Based upon this pattern of distribution, we selected a study region in Switzerland with a lower magnitude of isolation (Swiss Jura) and another study region in Germany with a higher degree of isolation (Franconian Jura). In each region, we chose ten populations to analyze population structure, reproduction, and genetic variation in a comparative approach. Therefore, we determined population density, cushion size, and cushion density to analyze population structure, investigated reproductive traits, including number of flowers, capsules, and germination rate, and analyzed amplified fragment length polymorphisms to study genetic variation. Population and cushion density were credibly higher in German than in Swiss populations, whereas reproductive traits and genetic variation within populations were similar in both study regions. However, genetic variation among populations and isolation by distance were stronger in Germany than in Switzerland. Generally, cushion size and density as well as flower and capsule production increased with population size and density, whereas genetic variation decreased with population density. In contrast to our assumptions, we observed denser populations and cushions in the region with the higher magnitude of isolation, whereas reproductive traits and genetic variation within populations were comparable in both regions. This corroborates the assumption that stronger isolation must not necessarily result in the loss of fitness and genetic variation. Furthermore, it supports our conclusion that the protection of strongly isolated populations contributes essentially to the conservation of a Species' full evolutionary potential.
N. Tero - One of the best experts on this subject based on the ideXlab platform.
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Local genetic population structure in an Endangered Plant Species, Silene tatarica (Caryophyllaceae)
Heredity, 2005Co-Authors: N. Tero, Jouni Aspi, Pirkko Siikamäki, Anne JäkäläniemiAbstract:Genetic substructuring in Plant populations may evolve as a consequence of sampling events that occur when the population is founded or regenerated, or if gene dispersal by pollen and seeds is restricted within a population . Silene tatarica is an Endangered, perennial Plant Species growing along periodically disturbed riverbanks in northern Finland. We investigated the mechanism behind the microspatial genetic structure of S. tatarica in four subpopulations using amplified fragment length polymorphism markers. Spatial autocorrelation revealed clear spatial genetic structure in each subpopulation, even though the pattern diminished in older subpopulations. Parentage analysis in an isolated island subpopulation indicated a very low level of selfing and avoidance of breeding between close relatives. The mean estimated pollen dispersal distance (24.10 m; SD=10.5) was significantly longer and the mean seed dispersal distance (9.07 m; SD=9.23) was considerably shorter than the mean distance between the individuals (19.20 m; SD=13.80). The estimated indirect and direct estimates of neighbourhood sizes in this subpopulation were very similar, 32.1 and 37.6, respectively. Our results suggested that the local spatial genetic structure in S. tatarica was attributed merely to the isolation-by-distance process rather than founder effect, and despite free pollen movement across population, restricted seed dispersal maintains local genetic structure in this Species.
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Local genetic population structure in an Endangered Plant Species, Silene tatarica (Caryophyllaceae).
Heredity, 2005Co-Authors: N. Tero, Jouni Aspi, Pirkko Siikamäki, Anne JäkäläniemiAbstract:Local genetic population structure in an Endangered Plant Species, Silene tatarica (Caryophyllaceae)
Pirkko Siikamäki - One of the best experts on this subject based on the ideXlab platform.
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Management of three Endangered Plant Species in dynamic Baltic seashore meadows
Applied Vegetation Science, 2007Co-Authors: Pirjo Rautiainen, Pirkko Siikamäki, Taina Björnström, Marika Niemelä, Pia Arvola, Aija Degerman, Lauri Erävuori, Annamari Markkola, Juha Tuomi, Marko HyvärinenAbstract:Question: Arctophila fulva var. pendulina, Primula nutans var. jokelae and Puccinellia phryganodes are threatened early successional Species growing in the seashore meadows of the northern Baltic Sea. Patches formed by these Species are destined to be replaced by other Species during primary succession and in order to persist in the area they have to continuously colonize new areas. We studied whether the displacement of the Species could be slowed down and their sexual and/or vegetative reproduction enhanced by management targeted to surrounding vegetation. Location: Bothnian Bay, Baltic Sea, W Finland. Methods: Vegetation surrounding patches of all study Species was mown in four successional growing seasons. Moreover, the impact of additional soil turning on creating new favourable growing sites was tested for A. fulva. Results: Deterioration of suitable habitats of A. fulva and P. nutans was markedly slowed down by management and the vegetative and/or sexual reproduction of these Species was enhanced. In the case of P. phryganodes, however, no positive response to management was obtained. Conclusions: In order to improve the long-term persistence of these three Species successional vegetation changes should be slowed down and their dispersal and colonization success improved by continuous management of the populations. We further suggest that the colonization of new areas should be aided by transPlantations to the non-vegetated islets, which have recently risen from the sea and cannot be reached by means of dispersal.
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Local genetic population structure in an Endangered Plant Species, Silene tatarica (Caryophyllaceae)
Heredity, 2005Co-Authors: N. Tero, Jouni Aspi, Pirkko Siikamäki, Anne JäkäläniemiAbstract:Genetic substructuring in Plant populations may evolve as a consequence of sampling events that occur when the population is founded or regenerated, or if gene dispersal by pollen and seeds is restricted within a population . Silene tatarica is an Endangered, perennial Plant Species growing along periodically disturbed riverbanks in northern Finland. We investigated the mechanism behind the microspatial genetic structure of S. tatarica in four subpopulations using amplified fragment length polymorphism markers. Spatial autocorrelation revealed clear spatial genetic structure in each subpopulation, even though the pattern diminished in older subpopulations. Parentage analysis in an isolated island subpopulation indicated a very low level of selfing and avoidance of breeding between close relatives. The mean estimated pollen dispersal distance (24.10 m; SD=10.5) was significantly longer and the mean seed dispersal distance (9.07 m; SD=9.23) was considerably shorter than the mean distance between the individuals (19.20 m; SD=13.80). The estimated indirect and direct estimates of neighbourhood sizes in this subpopulation were very similar, 32.1 and 37.6, respectively. Our results suggested that the local spatial genetic structure in S. tatarica was attributed merely to the isolation-by-distance process rather than founder effect, and despite free pollen movement across population, restricted seed dispersal maintains local genetic structure in this Species.
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Local genetic population structure in an Endangered Plant Species, Silene tatarica (Caryophyllaceae).
Heredity, 2005Co-Authors: N. Tero, Jouni Aspi, Pirkko Siikamäki, Anne JäkäläniemiAbstract:Local genetic population structure in an Endangered Plant Species, Silene tatarica (Caryophyllaceae)
Rien Aerts - One of the best experts on this subject based on the ideXlab platform.
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climate change threatens Endangered Plant Species by stronger and interacting water related stresses
Journal of Geophysical Research, 2011Co-Authors: Ruud P. Bartholomeus, Jan-philip M. Witte, Peter M. Van Bodegom, Jos Van Dam, Rien AertsAbstract:[1] Atmospheric CO2-concentration, temperature and rainfall variability are all expected to increase in the near future. The resulting increased dynamics of soil moisture contents, together with increased Plant physiological demands for both oxygen and water, will lead to an increased occurrence of wet and dry extremes of Plant stresses, i.e., of oxygen and drought stress, respectively, alone and in interaction. The use of indirect environmental variables in previous studies and a focus on individual stresses rather than their combined effects has hampered understanding of the causal impact of climate change on Plant Species composition through changes in abiotic site conditions. Here, we use process-based simulations of oxygen and drought stresses in conjunction with a downscaled national version of IPCC scenarios in order to show that these stresses will increase (on average by ∼20% at sites where both stresses occur) in a warmer and more variable future (2050) climate. These two types of stresses will increasingly coincide, i.e. both stresses will occur more often (but not at the same time) within a single vegetation plot. We further show that this increased coincidence of water-related stresses will negatively affect the future occurrence of currently Endangered Plant Species (causing a reduction of ∼16%), while apparently no such decrease will occur among common Species. Individual stresses did not appear to affect the occurrence of Endangered Plant Species. Consequently, our study demonstrates that Species that are already threatened under the current climate will suffer most from the effects of climate change.
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Climate change threatens Endangered Plant Species by stronger and interacting water‐related stresses
Journal of Geophysical Research, 2011Co-Authors: Ruud P. Bartholomeus, Jan-philip M. Witte, Peter M. Van Bodegom, Jos Van Dam, Rien AertsAbstract:[1] Atmospheric CO2-concentration, temperature and rainfall variability are all expected to increase in the near future. The resulting increased dynamics of soil moisture contents, together with increased Plant physiological demands for both oxygen and water, will lead to an increased occurrence of wet and dry extremes of Plant stresses, i.e., of oxygen and drought stress, respectively, alone and in interaction. The use of indirect environmental variables in previous studies and a focus on individual stresses rather than their combined effects has hampered understanding of the causal impact of climate change on Plant Species composition through changes in abiotic site conditions. Here, we use process-based simulations of oxygen and drought stresses in conjunction with a downscaled national version of IPCC scenarios in order to show that these stresses will increase (on average by ∼20% at sites where both stresses occur) in a warmer and more variable future (2050) climate. These two types of stresses will increasingly coincide, i.e. both stresses will occur more often (but not at the same time) within a single vegetation plot. We further show that this increased coincidence of water-related stresses will negatively affect the future occurrence of currently Endangered Plant Species (causing a reduction of ∼16%), while apparently no such decrease will occur among common Species. Individual stresses did not appear to affect the occurrence of Endangered Plant Species. Consequently, our study demonstrates that Species that are already threatened under the current climate will suffer most from the effects of climate change.