| 1. |
- Ahlberg, Erik, et al.
(författare)
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"Vi klimatforskare stödjer Greta och skolungdomarna"
- 2019
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Ingår i: Dagens nyheter (DN debatt). - 1101-2447.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- DN DEBATT 15/3. Sedan industrialiseringens början har vi använt omkring fyra femtedelar av den mängd fossilt kol som får förbrännas för att vi ska klara Parisavtalet. Vi har bara en femtedel kvar och det är bråttom att kraftigt reducera utsläppen. Det har Greta Thunberg och de strejkande ungdomarna förstått. Därför stödjer vi deras krav, skriver 270 klimatforskare.
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| 2. |
- Ellstrand, Norman C., et al.
(författare)
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Gene flow and introgression from domesticated plants into their wild relatives
- 1999
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Ingår i: Annual Review of Ecology and Systematics. - : Annual Reviews. - 0066-4162. ; 30, s. 539-563
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Tidskriftsartikel (refereegranskat)abstract
- Domesticated plant taxa cannot be regarded as evolutionarily discrete from their wild relatives. Most domesticated plant taxa mate with wild relatives somewhere in the world, and gene flow from crop taxa may have a substantial impact on the evolution of wild populations. In a literature review of the world's 13 most important food crops, we show that 12 of these crops hybridize with wild relatives in some part of their agricultural distribution. We use population genetic theory to predict the evolutionary consequences of gene flow from crops to wild plants and discuss two applied consequences of crop-to-wild gene flow-the evolution of aggressive weeds and the extinction of rare species. We suggest ways of assessing the likelihood of hybridization, introgression, and the potential for undesirable gene flow from crops into weeds or rare species.
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| 3. |
- Li, Yuanzhi, et al.
(författare)
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Habitat filtering determines the functional niche occupancy of plant communities worldwide
- 2018
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Ingår i: Journal of Ecology. - : Wiley. - 0022-0477 .- 1365-2745. ; 106:3, s. 1001-1009
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Tidskriftsartikel (refereegranskat)abstract
- How the patterns of niche occupancy vary from species-poor to species-rich communities is a fundamental question in ecology that has a central bearing on the processes that drive patterns of biodiversity. As species richness increases, habitat filtering should constrain the expansion of total niche volume, while limiting similarity should restrict the degree of niche overlap between species. Here, by explicitly incorporating intraspecific trait variability, we investigate the relationship between functional niche occupancy and species richness at the global scale. We assembled 21 datasets worldwide, spanning tropical to temperate biomes and consisting of 313 plant communities representing different growth forms. We quantified three key niche occupancy components (the total functional volume, the functional overlap between species and the average functional volume per species) for each community, related each component to species richness, and compared each component to the null expectations. As species richness increased, communities were more functionally diverse (an increase in total functional volume), and species overlapped more within the community (an increase in functional overlap) but did not more finely divide the functional space (no decline in average functional volume). Null model analyses provided evidence for habitat filtering (smaller total functional volume than expectation), but not for limiting similarity (larger functional overlap and larger average functional volume than expectation) as a process driving the pattern of functional niche occupancy. Synthesis. Habitat filtering is a widespread process driving the pattern of functional niche occupancy across plant communities and coexisting species tend to be more functionally similar rather than more functionally specialized. Our results indicate that including intraspecific trait variability will contribute to a better understanding of the processes driving patterns of functional niche occupancy.
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| 4. |
- Löfgren, Oskar, et al.
(författare)
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Landscape history confounds the ability of the NDVI to detect fine-scale variation in grassland communities
- 2018
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Ingår i: Methods in Ecology and Evolution. - 2041-210X. ; 9:9, s. 2009-2018
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Tidskriftsartikel (refereegranskat)abstract
- The NDVI is a remotely sensed vegetation index that is frequently used in ecological studies. There is, however, a lack of studies that evaluate the ability of the NDVI to detect fine-scale variation in grassland plant community composition and species richness. Ellenberg indicators characterize the environmental preferences of plant species—and community-mean Ellenberg values have been used to explore the environmental drivers of community assembly. We used variation partitioning to test the ability of satellite-based NDVI to explain community-mean Ellenberg nutrient (mN) and moisture (mF) indices, and the richness of habitat-specialist species in dry grasslands of different ages. The grasslands represent a gradient of decreasing soil nutrient status. If community composition is determined by the responses of individual species to the underlying environmental conditions and if, at the same time, community composition determines the optical characteristics of the vegetation canopy, then positive relationships between the NDVI and mN and mF are expected. Many grassland specialists are intolerant of nutrient-rich soils. If specialist richness is negatively related to soil-nutrient levels, then a negative association between the NDVI and specialist richness is expected. However, because grassland community composition is not only influenced by abiotic variables but also by other spatial and temporal drivers, we included spatial variables and grassland age in the statistical analyses. The NDVI explained the majority of the variation in mF, and also contributed to a substantial proportion of the variation in mN. However, variation in specialist richness and the lowest values of mN were explained by grassland age and spatial variables—but were poorly explained by the NDVI. Synthesis and applications. The NDVI showed a good ability to detect variation in plant community composition, and should provide a valuable tool for assessing fine-scale environmental variation in grasslands or for monitoring changes in grassland habitat properties. However, because the concentration of grassland specialists not only depends on environmental variables but also on the age and spatial context of the grasslands, the NDVI is unlikely to allow the identification of grasslands with high numbers of specialist species.
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| 5. |
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| 6. |
- Schmid, Barbara C., et al.
(författare)
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The contribution of successional grasslands to the conservation of semi-natural grasslands species – A landscape perspective
- 2017
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Ingår i: Biological Conservation. - : Elsevier BV. - 0006-3207. ; 206, s. 112-119
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Tidskriftsartikel (refereegranskat)abstract
- Many species that are typical of calcareous, semi-natural grasslands (“typical grassland species”) are declining in Europe as a result of habitat-loss and -fragmentation. Whereas populations of these species are expected to be largest in old semi-natural grasslands, these species may also occur in successional grasslands on previously arable fields. We used a space-for-time approach to analyse changes in the frequencies of typical grassland species, and changes in soil properties, over a 280-year arable-to-grassland succession within a Swedish landscape. Our study revealed that a number of typical grassland species had higher frequencies in mid-successional (50–279 years) than in old (≥ 280 years) grasslands. Mid-successional grasslands also contained many of the typical grassland species that were present in old grasslands, but at lower frequencies, and had soil conditions similar to those of old grasslands. Early-successional (5–14 and 15–49 years) grasslands contained few typical grassland species. In highly fragmented landscapes, mid-successional grasslands provide additional habitat for many typical grassland species, and can function as temporary refugia (“substitute habitat”) for these species until old grasslands are “restored”. The overall population sizes of some typical grassland species and red-listed species are likely to be substantially increased by the presence of mid-successional grasslands within the landscape. Our study suggests that, rather than focussing solely on old grassland fragments, conservation strategies for typical grassland species should adopt a dynamic, landscape-based perspective that recognizes the role of successional grasslands. Ensuring a continuous development of mid-successional grasslands is expected to be beneficial for populations of many typical grassland species.
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| 7. |
- Andersson, Stefan, et al.
(författare)
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Paternal effects on seed germination: a barrier to the genetic assimilation of an endemic plant taxon?
- 2008
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Ingår i: Journal of evolutionary biology. - : Wiley. - 1420-9101 .- 1010-061X. ; 21:5, s. 1408-1417
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Tidskriftsartikel (refereegranskat)abstract
- We used a crossing experiment to investigate post-zygotic barriers that might limit introgression between a pair of closely-related, gynodioecious plant species - the widespread weed Silene vulgaris and the local Swedish endemic S. uniflora ssp. petraea. The study not only considered the effects of hybridization on conventionally-used (primary) fitness components such as seed set and progeny survival, but also provided a test for the effects of interspecific hybridization on characters with more subtle or habitat-specific effects on fitness. We detected highly significant paternal effects on seed germination properties, with the germination characteristics of hybrid seed resembling those of the species that served as the pollen donor. These paternal effects on germination represent a potentially strong barrier to interspecific introgression in the two species' natural habitats, where an inappropriate germination response in the habitat of the maternal parent may lead to the failure of seedling establishment. Interspecific crosses had weak or variable effects on progeny survival, flowering and sex ratio, but these effects could not be interpreted in terms of barriers to introgression. Our results indicate that nuclear restorers in S. vulgaris have the capacity to suppress cytoplasmic male-sterility genes in its endemic congener.
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| 8. |
- Backeus, Ingvar, et al.
(författare)
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Minnesord Eddy van der Maarel
- 2021
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Ingår i: Upsala Nya Tidning. - 1104-0173.
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 9. |
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| 10. |
- Biurrun, Idoia, et al.
(författare)
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Benchmarking plant diversity of Palaearctic grasslands and other open habitats
- 2021
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Ingår i: Journal of Vegetation Science. - Oxford : John Wiley & Sons. - 1100-9233 .- 1654-1103. ; 32:4
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Tidskriftsartikel (refereegranskat)abstract
- Journal of Vegetation Science published by John Wiley & Sons Ltd on behalf of International Association for Vegetation Science.Aims: Understanding fine-grain diversity patterns across large spatial extents is fundamental for macroecological research and biodiversity conservation. Using the GrassPlot database, we provide benchmarks of fine-grain richness values of Palaearctic open habitats for vascular plants, bryophytes, lichens and complete vegetation (i.e., the sum of the former three groups). Location: Palaearctic biogeographic realm. Methods: We used 126,524 plots of eight standard grain sizes from the GrassPlot database: 0.0001, 0.001, 0.01, 0.1, 1, 10, 100 and 1,000 m2 and calculated the mean richness and standard deviations, as well as maximum, minimum, median, and first and third quartiles for each combination of grain size, taxonomic group, biome, region, vegetation type and phytosociological class. Results: Patterns of plant diversity in vegetation types and biomes differ across grain sizes and taxonomic groups. Overall, secondary (mostly semi-natural) grasslands and natural grasslands are the richest vegetation type. The open-access file ”GrassPlot Diversity Benchmarks” and the web tool “GrassPlot Diversity Explorer” are now available online (https://edgg.org/databases/GrasslandDiversityExplorer) and provide more insights into species richness patterns in the Palaearctic open habitats. Conclusions: The GrassPlot Diversity Benchmarks provide high-quality data on species richness in open habitat types across the Palaearctic. These benchmark data can be used in vegetation ecology, macroecology, biodiversity conservation and data quality checking. While the amount of data in the underlying GrassPlot database and their spatial coverage are smaller than in other extensive vegetation-plot databases, species recordings in GrassPlot are on average more complete, making it a valuable complementary data source in macroecology. © 2021 The Authors.
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| 11. |
- Dalmayne, Jonas, et al.
(författare)
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Assessment of fine-scale plant species beta diversity using WorldView-2 satellite spectral dissimilarity
- 2013
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Ingår i: Ecological Informatics. - : Elsevier BV. - 1574-9541. ; 18:november, s. 1-9
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Tidskriftsartikel (refereegranskat)abstract
- Plant species beta diversity is influenced by spatial heterogeneity in the environment. This heterogeneity can potentially be characterised with the help of remote sensing. We used WorldView-2 satellite data acquired over semi-natural grasslands on The Baltic island of Öland (Sweden) to examine whether dissimilarities in remote sensing response were related to fine-scale, between-plot dissimilarity (beta diversity) in non-woody vascular plant species composition within the grasslands. Fieldwork, including the on-site description of a set of 30 2 m × 2 m plots and a set of 30 4 m × 4 m plots, was performed to record the species dissimilarity between pairs of same-sized plots. Spectral data were extracted by associating each plot with a suite of differently sized pixel windows, and spectral dissimilarity was calculated between pairs of same-sized pixel windows. Relationships between spectral dissimilarity and beta diversity were analysed using univariate regression and partial least squares regression. The study revealed significant positive relationships between spectral dissimilarity and fine-scale (2 m × 2 m and 4 m × 4 m) between-plot species dissimilarity. The correlation between the predicted and the observed species dissimilarity was stronger for the set of large plots (4 m × 4 m) than for the set of small plots (2 m × 2 m), and the association between spectral and species data at both plot scales decreased when pixel windows larger than 3 × 3 pixels were used. We suggest that the significant relationship between spectral dissimilarity and species dissimilarity is a reflection of between-plot environmental heterogeneity caused by differences in grazing intensity (which result in between-plot differences in field-layer height, and amounts of biomass and litter). This heterogeneity is reflected in dissimilarities in both the species composition and the spectral response of the grassland plots. Between-plot dissimilarities in both spectral response and species composition may also be caused by between-plot variations in edaphic conditions. Our results indicate that high spatial resolution satellite data may potentially be able to complement field-based recording in surveys of fine-scale species diversity in semi-natural grasslands.
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| 12. |
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| 13. |
- de Bello, Francesco, et al.
(författare)
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Evidence for scale- and disturbance-dependent trait assembly patterns in dry semi-natural grasslands
- 2013
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Ingår i: Journal of Ecology. - : Wiley. - 1365-2745 .- 0022-0477. ; 101:5, s. 1237-1244
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Tidskriftsartikel (refereegranskat)abstract
- 1. The mechanisms driving nonrandom assembly patterns in plant communities have long been of interest in ecological research. Competing ecological theories predict that coexisting species may either be more functionally dissimilar than expected by chance (with functional divergence' mainly reflecting niche differentiation) or be functionally more similar than expected (with functional convergence' reflecting either the outcome of environmental filtering or weaker-competitor exclusion effects). Assembly patterns are usually assessed at a single scale and disturbance regime, whereas considering different spatial scales and disturbance regimes may clarify the underlying assembly mechanisms. 2. We tested the prediction that convergence and divergence are scale- and disturbance- dependent in grazed and abandoned species-rich dry grasslands within a 22km(2) landscape in south-eastern Sweden. Convergence and divergence were tested for plant species' traits and phylogenetic relationships at three nested spatial scales: within 412 plots (50x50cm, divided into 10x10cm subplots), within 117 grassland patches (from 0.02 to 11.63ha) and within the whole landscape (across patches). 3. At the finest scale (10x10cm subplots within plots), coexisting species were more different than expected by chance (divergence), both functionally and phylogenetically, suggesting niche differentiation. At the intermediate scale (50x50cm plots within patches), coexisting species showed convergence, suggesting environmental filtering. No significant deviations from random expectations were detected at the broadest scale (patches within the 22km(2) landscape) - suggesting the prevalence of dispersal limitation at this scale. The fact that nonrandom patterns were particularly evident under grazed conditions is consistent with the prediction that assembly patterns are disturbance dependent. 4. Synthesis. This study shows that multiple trait-based assembly processes operate simultaneously in species-rich communities, across spatial scales and disturbance regimes. The results support earlier theoretical predictions that divergence between coexisting species may be an important driver of community assembly, particularly at finer spatial scales, where species compete for the same local resources. In contrast, environmental filtering is expected at broader spatial scales, where species growing in particular environmental conditions share traits that are adaptive under those conditions. Within given habitat types, dispersal limitation may, however, override environmental filtering at increasing spatial scales of observation.
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| 14. |
- Dengler, Juergen, et al.
(författare)
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GrassPlot - a database of multi-scale plant diversity in Palaearctic grasslands
- 2018
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Ingår i: Phytocoenologia. - : Schweizerbart. - 0340-269X. ; 48:3, s. 331-347
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Tidskriftsartikel (refereegranskat)abstract
- GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). GrassPlot collects plot records (releves) from grasslands and other open habitats of the Palaearctic biogeographic realm. It focuses on precisely delimited plots of eight standard grain sizes (0.0001; 0.001;... 1,000 m(2)) and on nested-plot series with at least four different grain sizes. The usage of GrassPlot is regulated through Bylaws that intend to balance the interests of data contributors and data users. The current version (v. 1.00) contains data for approximately 170,000 plots of different sizes and 2,800 nested-plot series. The key components are richness data and metadata. However, most included datasets also encompass compositional data. About 14,000 plots have near-complete records of terricolous bryophytes and lichens in addition to vascular plants. At present, GrassPlot contains data from 36 countries throughout the Palaearctic, spread across elevational gradients and major grassland types. GrassPlot with its multi-scale and multi-taxon focus complements the larger international vegetationplot databases, such as the European Vegetation Archive (EVA) and the global database " sPlot". Its main aim is to facilitate studies on the scale-and taxon-dependency of biodiversity patterns and drivers along macroecological gradients. GrassPlot is a dynamic database and will expand through new data collection coordinated by the elected Governing Board. We invite researchers with suitable data to join GrassPlot. Researchers with project ideas addressable with GrassPlot data are welcome to submit proposals to the Governing Board.
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| 15. |
- Ekroos, Johan, et al.
(författare)
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Sparing land for biodiversity at multiple spatial scales
- 2016
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Ingår i: Frontiers in Ecology and Evolution. - : Frontiers Media SA. - 2296-701X. ; 3
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Tidskriftsartikel (refereegranskat)abstract
- A common approach to the conservation of farmland biodiversity and the promotion of multifunctional landscapes, particularly in landscapes containing only small remnants of non-crop habitats, has been to maintain landscape heterogeneity and reduce land-use intensity. In contrast, it has recently been shown that devoting specific areas of non-crop habitats to conservation, segregated from high-yielding farmland (“land sparing”), can more effectively conserve biodiversity than promoting low-yielding, less intensively managed farmland occupying larger areas (“land sharing”). In the present paper we suggest that the debate over the relative merits of land sparing or land sharing is partly blurred by the differing spatial scales at which it is suggested that land sparing should be applied. We argue that there is no single correct spatial scale for segregating biodiversity protection and commodity production in multifunctional landscapes. Instead we propose an alternative conceptual construct, which we call “multiple-scale land sparing,” targeting biodiversity and ecosystem services in transformed landscapes. We discuss how multiple-scale land sparing may overcome the apparent dichotomy between land sharing and land sparing and help to find acceptable compromises that conserve biodiversity and landscape multifunctionality.
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| 16. |
- Ellmer, Maarten, et al.
(författare)
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The structuring of quantitative genetic variation in a fragmented population of Briza media (Poaceae)
- 2011
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Ingår i: Evolutionary Ecology. - : Springer Science and Business Media LLC. - 1573-8477 .- 0269-7653. ; 25:2, s. 509-523
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Tidskriftsartikel (refereegranskat)abstract
- The structuring of quantitative genetic variation can have a significant impact on the adaptive potential and long-term viability of species in changing landscapes. The present study of the grass Briza media investigated the relationships between patterns of heritable variation in phenotypic characters and descriptors of landscape structure, land-use history and local habitat conditions in a landscape known to have undergone a progressive and massive loss of semi-natural grassland habitat over the past 300 years. Our analyses revealed significant levels of heritable variation for characters related to overall plant size and spikelet size-number ratio, with estimates of broad-sense heritability ranging between 29 and 34%. Differences between demes accounted for a minor fraction of the total variation. In contrast to previous allozyme results from the same plant material, which suggest significant impacts of both neutral and selective processes, neither the deme-specific means nor the heritabilities for the phenotypic characters were consistently associated with landscape structure or land-use history. The results of the study indicate that the structuring of quantitative variation has been relatively insensitive to habitat fragmentation, at least over the time frame considered in this study system.
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| 17. |
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| 18. |
- Ericson, Lars, et al.
(författare)
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Bevara de värdefulla skogar som ännu finns kvar i Sverige
- 2017
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Ingår i: Dagens nyheter (DN debatt). - 1101-2447.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- DN Debatt: Sverige har åtagit sig att skydda 20 procent av landets land- och sötvattensområden till 2020. Men hittills har bara 4–5 procent av den omfattande produktiva skogen bevarats. För att nå de demokratiskt beslutade målen måste Skogsstyrelsens beslut om stopp för inventering av nyckelbiotoper hävas, skriver sju forskare.
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| 19. |
- Hall, Karin, et al.
(författare)
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Inventorying management status and plant species richness in semi-natural grasslands using high spatial resolution imagery
- 2010
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Ingår i: Applied Vegetation Science. - 1402-2001. ; 13:2, s. 221-233
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Tidskriftsartikel (refereegranskat)abstract
- Question Can we reliably estimate grazing intensity, indicators of grazing intensity (i.e. field-layer height and shrub-cover), and vascular plant species richness in semi-natural grasslands from high spatial resolution satellite data? Location The Baltic Island of Oland (Sweden). Methods Fieldwork included the on-site description of grazed and ungrazed areas and shrub-cover within 107 semi-natural grassland sites. Field-layer height and vascular plant species richness (total within-site and mean small-scale species richness) were recorded within the sites. Digital classification of QuickBird data was performed to identify grazed and ungrazed areas and shrub-cover. Vegetation indices were generated to analyze the performance of satellite data for estimating field-layer height, and the spectral heterogeneity was used to characterize the within-site environmental heterogeneity. Results The proportion of digitally classified grazed area explained 45% of the variation in field-layer height and 43% of the variation in shrub-cover. Field-layer height was significantly related to vegetation indices. A linear model with three explanatory variables (spectral richness(red), spectral richness(NIR), and shrub-cover) explained 47% of the variation in total within-site species richness. Conclusions High spatial resolution imagery may assist in the monitoring of the processes that follow the cessation of grazing, on the scale of individual grassland sites. Measures of spectral heterogeneity acquired by high spatial resolution imagery can be used in the assessment of total within-site vascular plant species richness in semi-natural grassland vegetation.
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| 20. |
- Hall, Karin, et al.
(författare)
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Spectral heterogeneity of QuickBird satellite data is related to fine-scale plant species spatial turnover in semi-natural grasslands
- 2012
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Ingår i: Applied Vegetation Science. - 1402-2001. ; 15:1, s. 145-157
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Tidskriftsartikel (refereegranskat)abstract
- Abstract Question: Can satellite data be related to fine-scale species diversity and does the integrated use of field and satellite data provide information that can be used in the estimation of fine-scale species diversity in semi-natural grassland sites? Location: The Baltic Island of Oland (Sweden). Methods: Field work including the on-site description of 62 semi-natural grassland sites (represented by three 0.5m0.5m plots per site) was performed to record response variables (total species richness, mean species richness and species spatial turnover) and field-measured explanatory variables (field-layer height and distance between plots). Within each site, QuickBird satellite data were extracted from a standardized sample area by associating each field plot with a 33 pixel window (1 pixel = 2.4m2.4 m). Explanatory variables (the normalized difference vegetation index and spectral heterogeneity) were generated from the satellite data. Correlation tests, univariate regressions, variance partitioning and multivariate linear regressions were used to analyse the associations between response and explanatory variables. Results: There was a significant association between the spectral heterogeneity of the near-infrared band and the field-measured spatial turnover of species. The most parsimonious explanatory model for each response variable included both field-measured and satellite-generated explanatory variables. The models explained 30–35% of the variation in species diversity (total richness 36%, mean richness 31%, species turnover 33%). Conclusions: High spatial resolution satellite data are capable of supplying fine-scale habitat information that is relevant for the monitoring and conservation management of fine-scale plant diversity in semi-natural grasslands.
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| 21. |
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| 22. |
- Hathaway, Louise, et al.
(författare)
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Experimental crosses within European Silene latifolia (Caryophyllaceae): intraspecific differentiation, distance effects, and sex ratio
- 2009
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Ingår i: Canadian Journal of Botany. - 0008-4026. ; 87:3, s. 231-240
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Tidskriftsartikel (refereegranskat)abstract
- The dioecious weed Silene latifolia Poiret is thought to have spread northwards through Europe from separate southern source populations and shows a pronounced east–west pattern of differentiation in seed morphology. We used crossing experiments to investigate whether patterns of interfertility in S. latifolia are consistent with a scenario of ongoing speciation (reflected by outbreeding depression in crosses between the seed races), a scenario involving local inbreeding (reflected by heterosis in interpopulations crosses), or a combination of both scenarios. The experiments involved three western and three eastern populations, which were crossed reciprocally in all possible inter- and intra-population combinations. Inter-race cross-progenies did not have lower fitness than those from intra-racial crosses, and the results are not consistent with a scenario of incipient speciation. A pattern of overall heterosis was found in three variables, indicating the expression of inbreeding depression in progeny from intrapopulation crosses. For two fitness variables, negative relationships between interpopulation distance and heterosis, together with signs of outbreeding depression in the longest-distance crosses, suggest that there may be significant levels of genetic differentiation between geographically distant populations. The sex ratio was female-biased in most progenies, especially in those from the longest-distance crosses.
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| 23. |
- Hathaway, Louise, et al.
(författare)
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Geographically congruent large-scale patterns of plastid haplotype variation in the European herbs Silene dioica and S-latifolia (Caryophyllaceae)
- 2009
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Ingår i: Botanical Journal of the Linnean Society. - 1095-8339. ; 161:2, s. 153-170
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Tidskriftsartikel (refereegranskat)abstract
- The closely related dioecious herbs Silene latifolia and Silene dioica are widespread and predominantly sympatric in Europe. The species are interfertile, but morphologically and ecologically distinct. A study of large-scale patterns of plastid DNA (polymerase chain reaction-restriction fragment length polymorphism) haplotypes in a sample of 198 populations from most of the European ranges of both species revealed extensive interspecific haplotype sharing. Four of the 28 detected haplotypes were frequent (found in > 40 populations) and widespread. Three of these frequent haplotypes occurred in both species and the geographic distribution of each haplotype was broadly congruent in both species. Each of these three, shared and widespread haplotypes is likely to have colonized central and/or northern Europe after the last glaciation from one or more of refugial areas in southern Europe. Interspecific hybridization and plastid introgression within refugial regions and/or during the early stages of postglacial expansion is the most plausible explanation for the broadly similar distribution patterns of the shared, frequent chloroplast haplotypes in the two species. The fourth frequent, widespread haplotype was absent from S. latifolia and almost entirely restricted to Nordic S. dioica. It is most likely that this haplotype spread into the Nordic countries from a central or northern European source or from a refugial area in Russia. (c) 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 161, 153-170.
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| 24. |
- Irminger Street, Therese, et al.
(författare)
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Predicted effects of management on vascular plant species in arable field margins
- 2010
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Ingår i: Aspects of Applied Biology. - 0265-1491. ; 100, s. 233-243
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Tidskriftsartikel (refereegranskat)abstract
- Many of Sweden’s red listed species are found in the agricultural landscape. Small biotopes (e.g. field margins and field islets) are important for the maintenance of biodiversity in agricultural landscapes, and agri-environmental support is paid to farmers who keep them open. However, a proper evaluation of the biodiversity-gains from this type of management is lacking. We examined the predicted response of vascular plant species in field margins in Scania, S. Sweden, to the removal of woody vegetation and found that more species are expected to show a positive than a negative response to this type of management. Comparison of present-day and historical (1940s) aerial photographs shows that field size and the amount of small biotopes have decreased while the cover of woody vegetation on many of the remaining small biotopes has increased. Changes are greater in the arable plains and in the mixed district than in the forest district.
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| 25. |
- Irminger Street, Therese, et al.
(författare)
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Removal of woody vegetation from uncultivated field margins is insufficient to promote non-woody vascular plant diversity
- 2015
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Ingår i: Agriculture, Ecosystems & Environment. - : Elsevier BV. - 1873-2305 .- 0167-8809. ; 201, s. 1-10
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Tidskriftsartikel (refereegranskat)abstract
- Uncultivated field margins are one of the most frequent non-crop habitat types in contemporary, highintensity agricultural landscapes and may therefore be important for the persistence of many farmland species. Managing field margins in a way that preserves, and preferably enhances, their value for biodiversity is therefore important. In the present study, we evaluate how the flora of uncultivated field margins is affected by the removal of woody vegetation as prescribed by an agri-environment scheme (AES) under the Swedish Rural Development Program 2007–2013. We used generalized linear mixed models and detrended correspondence analysis to compare the flora of open (cleared) and more overgrown field margins, located within agricultural landscapes of different complexity, in Scania, S. Sweden. As expected, there was a negative effect of management on woody species. However, the local (1m2) and transect (100 m) level richness of non-woody species did not differ significantly between management categories, and there were no differences in the within-transect variability of non-woody species (local b diversity) or the species composition (0.25m2 plots) in managed and unmanaged field margins. Our results show that the removal of woody vegetation from uncultivated field margins, as prescribed by the evaluated AES, is unlikely to benefit non-woody plant species. The species composition of the sampled field margins suggests that inclusion of appropriate field layer management alone is unlikely to be sufficient to improve habitat conditions for grassland species unless measures are taken to counteract eutrophication. Landscape type, on the other hand, influenced both the total richness and the richness of each of the species groups that were considered to be of particular conservation value in the present study: field margins in the complex agricultural landscapes were significantly richer than those in the simple ones. Maintaining non-crop habitat at the landscape scale is likely to be a necessary first step in the prevention of a further decline of farmland plants.
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| 26. |
- Jeliazkov, Alienor, et al.
(författare)
-
A global database for metacommunity ecology, integrating species, traits, environment and space
- 2020
-
Ingår i: Scientific Data. - : Springer Science and Business Media LLC. - 2052-4463. ; 7:1
-
Tidskriftsartikel (refereegranskat)abstract
- The use of functional information in the form of species traits plays an important role in explaining biodiversity patterns and responses to environmental changes. Although relationships between species composition, their traits, and the environment have been extensively studied on a case-by-case basis, results are variable, and it remains unclear how generalizable these relationships are across ecosystems, taxa and spatial scales. To address this gap, we collated 80 datasets from trait-based studies into a global database for metaCommunity Ecology: Species, Traits, Environment and Space; “CESTES”. Each dataset includes four matrices: species community abundances or presences/absences across multiple sites, species trait information, environmental variables and spatial coordinates of the sampling sites. The CESTES database is a live database: it will be maintained and expanded in the future as new datasets become available. By its harmonized structure, and the diversity of ecosystem types, taxonomic groups, and spatial scales it covers, the CESTES database provides an important opportunity for synthetic trait-based research in community ecology. © 2020, The Author(s).
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| 27. |
- Johansson, Lotten, et al.
(författare)
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Semi-natural grassland continuity, long-term land-use change and plant species richness in a local agricultural landscape on Öland, Sweden
- 2008
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Ingår i: Landscape and Urban Planning. - : Elsevier BV. - 0169-2046 .- 1872-6062. ; :84, s. 200-211
-
Tidskriftsartikel (refereegranskat)abstract
- The study characterizes historical land-use change and the development of semi-natural grassland habitats, over 274 years, within a mosaic agricultural landscape (22 km2) on the island of O¨ land (Sweden). We also explore the relationship between previous land-use, habitat continuity and present-day vascular plant species richness in grassland patches.Land-cover maps, based on cadastral maps and aerial photographs, wereproduced for six time-periods between 1723/1733 and 1994/1997. In 1723/1733, the landscape was dominated by grasslands, with arable land surrounding the villages. The grassland area decreased throughout the study period and grassland patches became progressively more fragmented.Present-day grasslands represent 18% of the grassland area in 1723/1733. The land-use structure of the early 18th century is still evident in the modern landscape. The majority of the present-day grasslands are situated on former common grazing land and have had a continuity of at least 274 years: the remaining grasslands are younger and developed during the 20th century on arable or forested land.The proportion of plant speciesthat depend on grazing and are characteristic of semi-natural grasslands significantly reflects the continuity and previous land-use of grassland sites. The study illustrates the way in which information on historical land-use and habitat continuity can help to explain the structuring of plant assemblages in semi-natural grasslands within the modern landscape.
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| 28. |
- Jonsell, Bengt, et al.
(författare)
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Silene uniflora Roth ssp. petaea (Hartm.)
- 1996
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Ingår i: Lectotypifications and new combinations for Flora Nordica vol 1(Lycopodiaceae - Papaveraceae). ; 16, s. 6-6
-
Bokkapitel (refereegranskat)
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| 29. |
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| 30. |
- Li, Yuan, et al.
(författare)
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Contrasting patterns of nucleotide polymorphism suggest different selective regimes within different parts of the PgiC1 gene in Festuca ovina L
- 2017
-
Ingår i: Hereditas. - : Springer Science and Business Media LLC. - 1601-5223. ; 154
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Phosphoglucose isomerase (PGI, EC 5.3.1.9) is an essential metabolic enzyme in all eukaryotes. An earlier study of the PgiC1 gene, which encodes cytosolic PGI in the grass Festuca ovina L., revealed a marked difference in the levels of nucleotide polymorphism between the 5' and 3' portions of the gene.METHODS: In the present study, we characterized the sequence polymorphism in F. ovina PgiC1 in more detail and examined possible explanations for the non-uniform pattern of nucleotide polymorphism across the gene.RESULTS: Our study confirms that the two portions of the PgiC1 gene show substantially different levels of DNA polymorphism and also suggests that the peptide encoded by the 3' portion of PgiC1 is functionally and structurally more important than that encoded by the 5' portion. Although there was some evidence of purifying selection (dN/dS test) on the 5' portion of the gene, the signature of purifying selection was considerably stronger on the 3' portion of the gene (dN/dS and McDonald-Kreitman tests). Several tests support the action of balancing selection within the 5' portion of the gene. Wall's B and Q tests were significant only for the 5' portion of the gene. There were also marked peaks of nucleotide diversity, Tajima's D and the dN/dS ratio at or around a PgiC1 codon site (within the 5' portion of the gene) that a previous study had suggested was subject to positive diversifying selection.CONCLUSIONS: Our results suggest that the two portions of the gene have been subject to different selective regimes. Purifying selection appears to have been the main force contributing to the relatively low level of polymorphism within the 3' portion of the sequence. In contrast, it is possible that balancing selection has contributed to the maintenance of the polymorphism within the 5' portion of the gene.
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| 31. |
- Li, Yuan, et al.
(författare)
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Evidence for Positive Selection within the PgiC1 Locus in the Grass Festuca ovina.
- 2015
-
Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 10:5
-
Tidskriftsartikel (refereegranskat)abstract
- The dimeric metabolic enzyme phosphoglucose isomerase (PGI, EC 5.3.1.9) plays an essential role in energy production. In the grass Festuca ovina, field surveys of enzyme variation suggest that genetic variation at cytosolic PGI (PGIC) may be adaptively important. In the present study, we investigated the molecular basis of the potential adaptive significance of PGIC in F. ovina by analyzing cDNA sequence variation within the PgiC1 gene. Two, complementary, types of selection test both identified PGIC1 codon (amino acid) sites 200 and 173 as candidate targets of positive selection. Both candidate sites involve charge-changing amino acid polymorphisms. On the homology-modeled F. ovina PGIC1 3-D protein structure, the two candidate sites are located on the edge of either the inter-monomer boundary or the inter-domain cleft; examination of the homology-modeled PGIC1 structure suggests that the amino acid changes at the two candidate sites are likely to influence the inter-monomer interaction or the domain-domain packing. Biochemical studies in humans have shown that mutations at several amino acid sites that are located close to the candidate sites in F. ovina, at the inter-monomer boundary or the inter-domain cleft, can significantly change the stability and/or kinetic properties of the PGI enzyme. Molecular evolutionary studies in a wide range of other organisms suggest that PGI amino acid sites with similar locations to those of the candidate sites in F. ovina may be the targets of positive/balancing selection. Candidate sites 200 and 173 are the only sites that appear to discriminate between the two most common PGIC enzyme electromorphs in F. ovina: earlier studies suggest that these electromorphs are implicated in local adaptation to different grassland microhabitats. Our results suggest that PGIC1 sites 200 and 173 are under positive selection in F. ovina.
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| 32. |
- Lindborg, Regina, et al.
(författare)
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Fel att offra betesmark i Sverige av klimatskäl
- 2019
-
Ingår i: Svenska Dagbladet, Stockholm. - 1101-2412.
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Ambitionen att minska köttkonsumtionen är lovvärd men riskerar att slå hårt mot den biologiska mångfalden och ekosystemtjänster. Om våra naturbetesmarker försvinner kan vi inte leva upp till FN:s internationella hållbarhetsmål och våra egna svenska miljömål som vi förbundit oss att jobba mot, skriver ett flertal forskare.
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| 33. |
- Lönn, Mikael, et al.
(författare)
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Gene diversity and demographic turnover in central and peripheral populations of the perennial herb, Gypsophila fastigiata
- 2002
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Ingår i: Oikos. - : Wiley. - 0030-1299 .- 1600-0706. ; 99:3, s. 489-498
-
Tidskriftsartikel (refereegranskat)abstract
- Within-population gene diversity (HS) was estimated (using allozyme markers) for 16 populations of the perennial, outcrossing plant, Gypsophila fastigiata, on the Baltic island of Öland. The populations were characterized by data on extent, density, life-stages, and habitat diversity. Populations were classed as central or peripheral in relation to the distribution of “alvar” (habitats with shallow, calcareous soils on limestone bedrock) on southern Öland. Three minimal adequate models were used to explain HS and the proportions of juveniles and dead adults. In the first model, HS was significantly lower in peripheral populations and there were no significant additional effects of other explanatory variables. The lower diversity in peripheral populations can be explained by a combination of genetic drift (in populations that vary in size in response to habitat fragmentation) and lower levels of interpopulation gene flow than in central populations. In the two life-stage models, peripheral populations had significantly larger proportions of both juveniles and dead adults – indicating a greater demographic turnover than in the central populations. There were also significant effects of HS and species diversity on the proportion of juveniles. The central or peripheral position of populations is the strongest predictor of both within-population gene diversity and life-stage dynamics in Öland G. fastigiata.
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| 34. |
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| 35. |
- Malm, J U, et al.
(författare)
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Chloroplast DNA haplotypes in Nordic Silene dioica: postglacial immigration from the east and the south
- 2005
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Ingår i: Plant Systematics and Evolution. - : Springer Science and Business Media LLC. - 1615-6110 .- 0378-2697. ; 250:1-2, s. 27-38
-
Tidskriftsartikel (refereegranskat)abstract
- Analysis of PCR/RFLP variation in 57 Nordic populations of the herb Silene dioica, revealed 13 composite chloroplast DNA (cpDNA) haplotypes. The geographic distribution of the haplotypes suggests that the postglacial colonization of Fennoscandia by S. dioica may have involved immigration of populations from two main directions. The commonest cpDNA haplotype dominates in populations throughout most of Finland and northern and central Sweden, but is absent from southern Sweden. The distribution of this haplotype is interpreted in terms of immigration from an eastern or northern direction. In contrast, eight haplotypes that are absent from northern Fennoscandia are represented in populations in southern Sweden and in Denmark, suggesting colonization by populations derived from one or several refugial areas further to the south in Europe. The overall NE-SW pattern of cpDNA haplotype variation is similar to, but less diffuse than, the pattern revealed by allozyme markers.
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| 36. |
- Malm, J U, et al.
(författare)
-
Immigration history and gene dispersal: allozyme variation in Nordic populations of the red campion, Silene dioica (Caryophyllaceae)
- 2002
-
Ingår i: Biological Journal of the Linnean Society. - : Oxford University Press (OUP). - 0024-4066 .- 1095-8312. ; 77:1, s. 23-34
-
Tidskriftsartikel (refereegranskat)abstract
- Most of the Nordic region was ice-covered during the last (Weichselian) glaciation. During the postglacial period, plant and animal species recolonized the region from several directions and the geographic structuring of genetic variation within Nordic species may still contain a historic component that reflects patterns of postglacial immigration. The present investigation of 69 populations of Silene dioica represents the first large-scale allozyme study of a widespread herbaceous plant in the Nordic region. Although the frequencies of individual alleles showed a range of different geographic patterns, mapping of the axis scores from an ordination of variation at eight polymorphic loci revealed a division into two main geographic groups of populations. The broadly south-western and northeastern distributions of these two groups of populations suggest that immigration into the region may have involved both eastern and southern geographic sources. However, the geographic boundaries between the two groups of populations are diffuse, and the relatively low between-population component of genetic diversity (G(ST) = 16.4%) suggests a history of extensive gene dispersal by pollen. (C) 2002 The Linnean Society of London, Biological Journal of the Linnean Society, 2002, 77, 23-34.
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| 37. |
- Moberg, Christina, et al.
(författare)
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De unga gör helt rätt när de stämmer staten
- 2022
-
Ingår i: Aftonbladet. - 1103-9000.
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- 1 620 forskare och lärare i forskarvärlden: Vi ställer oss bakom Auroras klimatkrav
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| 38. |
- Molau, U., et al.
(författare)
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Reproductive system and population structure in three arctic Saxifraga species
- 1992
-
Ingår i: Journal of Ecology. - : JSTOR. - 0022-0477. ; 80:1, s. 149-161
-
Tidskriftsartikel (refereegranskat)abstract
- Saxifraga cespitosa, S. tenuis and S. cernua were examined in the Abisko area, N Sweden. Populations of S. cespitosa were gynodioecious. Hermaphrodite individuals showed a high selfing efficiency and low pollen:ovule ratios, consistent with a lower outbreeding rate. Saxifraa tenuis was hermaphrodite with some indication of sexual asymmetry. Pollen:ovule ratios were low, but the ability to set seed by autodeposition was lower in S. tenuis than in S. cespitosa. Saxifraga cernua was androdioecious, with some populations that contained only female-sterile individuals and other populations with both female-sterile and hermaphrodite individuals. The higher production of bulbils by female-sterile individuals, coupled with self-incompatibility in hermaphrodites, suggests a means by which androdioecy may be maintained in S. cernua, in the absence of differences in male reproductive success between gender classes. Although all three species showed significant inter-population differentiation, the morphometric distances between populations were not related to the geographic distances between populations. Most of the total diversity in leaf shape was accounted for by inter-population differentiation in all three species, with <1% of the diversity due to variation within individuals. The mosaic pattern of variation in the three saxifrages is consistent with a scenario of localized founder effect and may still reflect patterns of recruitment after the deglaciation of the study area c8200BP. -from Authors
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| 39. |
- Möckel, Thomas, et al.
(författare)
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Airborne hyperspectral data predict Ellenberg indicator values for nutrient and moisture availability in dry grazed grasslands within a local agricultural landscape
- 2016
-
Ingår i: Ecological Indicators. - : Elsevier BV. - 1470-160X. ; 66, s. 503-516
-
Tidskriftsartikel (refereegranskat)abstract
- Species-based ecological indices, such as Ellenberg indicators, reflect plant habitat preferences and can be used to describe local environment conditions. One disadvantage of using vegetation data as a substitute for environmental data is the fact that extensive floristic sampling can usually only be carried out at a plot scale within limited geographical areas. Remotely sensed data have the potential to provide information on fine-scale vegetation properties over large areas. In the present study, we examine whether airborne hyperspectral remote sensing can be used to predict Ellenberg nutrient (N) and moisture (M) values in plots in dry grazed grasslands within a local agricultural landscape in southern Sweden. We compare the prediction accuracy of three categories of model: (I) models based on predefined vegetation indices (VIs), (II) models based on waveband-selected VIs, and (III) models based on the full set of hyperspectral wavebands. We also identify the optimal combination of wavebands for the prediction of Ellenberg values. The floristic composition of 104 (4 m × 4 m grassland) plots on the Baltic island of Öland was surveyed in the field, and the vascular plant species recorded in the plots were assigned Ellenberg indicator values for N and M. A community-weighted mean value was calculated for N (mN) and M (mM) within each plot. Hyperspectral data were extracted from an 8 m × 8 m pixel window centred on each plot. The relationship between field-observed and predicted mean Ellenberg values was significant for all three categories of prediction models. The performance of the category II and III models was comparable, and they gave lower prediction errors and higher R2 values than the category I models for both mN and mM. Visible and near-infrared wavebands were important for the prediction of both mN and mM, and shortwave infrared wavebands were also important for the prediction of mM. We conclude that airborne hyperspectral remote sensing can detect spectral differences in vegetation between grassland plots characterised by different mean Ellenberg N and M values, and that remote sensing technology can potentially be used to survey fine-scale variation in environmental conditions within a local agricultural landscape.
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| 40. |
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| 41. |
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| 42. |
- Möckel, Thomas, et al.
(författare)
-
Classification of grassland successional stages using airborne hyperspectral imagery
- 2014
-
Ingår i: Remote Sensing. - : MDPI AG. - 2072-4292. ; 6:8, s. 7732-7761
-
Tidskriftsartikel (refereegranskat)abstract
- Plant communities differ in their species composition, and, thus, also in their functional trait composition, at different stages in the succession from arable fields to grazed grassland. We examine whether aerial hyperspectral (414–2501 nm) remote sensing can be used to discriminate between grazed vegetation belonging to different grassland successional stages. Vascular plant species were recorded in 104.1 m2 plots on the island of Öland (Sweden) and the functional properties of the plant species recorded in the plots were characterized in terms of the ground-cover of grasses, specific leaf area and Ellenberg indicator values. Plots were assigned to three different grassland age-classes, representing 5–15, 16–50 and >50 years of grazing management. Partial least squares discriminant analysis models were used to compare classifications based on aerial hyperspectral data with the age-class classification. The remote sensing data successfully classified the plots into age-classes: the overall classification accuracy was higher for a model based on a pre-selected set of wavebands (85%, Kappa statistic value = 0.77) than one using the full set of wavebands (77%, Kappa statistic value = 0.65). Our results show that nutrient availability and grass cover differences between grassland age-classes are detectable by spectral imaging. These techniques may potentially be used for mapping the spatial distribution of grassland habitats at different successional stages.
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| 43. |
- Naciri, Yamama, et al.
(författare)
-
Convergent Morphological Evolution in Silene Sect. Italicae (Caryophyllaceae) in the Mediterranean Basin
- 2022
-
Ingår i: Frontiers in Plant Science. - : Frontiers Media SA. - 1664-462X. ; 13
-
Tidskriftsartikel (refereegranskat)abstract
- Recent divergence can obscure species boundaries among closely related taxa. Silene section Italicae (Caryophyllaceae) has been taxonomically controversial, with about 30 species described. We investigate species delimitation within this section using 500 specimens sequenced for one nuclear and two plastid markers. Despite the use of a small number of genes, the large number of sequenced samples allowed confident delimitation of 50% of the species. The delimitation of other species (e.g., Silene nemoralis, S. nodulosa and S. andryalifolia) was more challenging. We confirmed that seven of the ten chasmophyte species in the section are not related to each other but are, instead, genetically closer to geographically nearby species belonging to Italicae yet growing in open habitats. Adaptation to chasmophytic habitats therefore appears to have occurred independently, as a result of convergent evolution within the group. Species from the Western Mediterranean Basin showed more conflicting species boundaries than species from the Eastern Mediterranean Basin, where there are fewer but better-delimited species. Significant positive correlations were found between an estimation of the effective population size of the taxa and their extent of occurrence (EOO) or area of occupancy (AOO), and negative but non-significant correlations between the former and the posterior probability (PP) of the corresponding clades. These correlations might suggest a lower impact of incomplete lineage sorting in species with low effective population sizes and small distributional ranges compared with that in species inhabiting large areas. Finally, we confirmed that S. italica and S. nemoralis are distinct species, that S. nemoralis might furthermore include two different species and that S. velutina from Corsica and S. hicesiae from the Lipari Islands are sister species.
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| 44. |
- Olle, Jonsson B., et al.
(författare)
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Allozyme diversity and geographic variation in the widespread coastal sedge, Carex arenaria
- 2000
-
Ingår i: Diversity & distributions. - : Wiley. - 1366-9516 .- 1472-4642. ; 6:2, s. 65-80
-
Tidskriftsartikel (refereegranskat)abstract
- Allozyme electrophoresis was used to investigate the structure of genetic variation in the rhizomatous coastal sedge, Carex arenaria, throughout its European range - from the SW Iberian peninsula to the Baltic region. Material was sampled from 77 sites in five geographic regions. Nine of the 13 investigated loci were polymorphic in the total material and there were interregional differences in the number of polymorphic loci per site and the percentage of variable sites. In the Scandinavia/Baltic region only 61% of the sites contained at least one locus with more than one allele, whereas all the British and SW Iberian sites were variable. There was a general tendency for the regional frequencies of the less common alleles at individual loci to decline from SW to NE. The mean (over loci and sites) within-site gene diversity (H(site)) was 0.064 (in calculations based on the number of observed multilocus allozyme genotypes within each sampling site). Although there was considerable variation between geographically adjacent sites, within-site diversity showed a general decrease from SW to NE in Europe. There were significant differences in within-region gene diversity (H(reg)) for the four most variable loci between the five regions. H(reg) generally decreased from SW to NE Europe and most loci showed the highest diversity in the SW Iberian peninsula and the Bay of Biscay regions. The mean (over loci) gene diversity in the total material (H(tot)) was 0.070 and the levels of diversity in Carex arenaria are substantially lower than is usual in rhizomatous sedges. The within-site, between-site and between-regional components of the total diversity were 92.4%, 2.5% and 5.1%, respectively. The low levels of overall gene diversity in C. arenaria and the successive decrease in diversity from SW to NE are interpreted in terms of the species' history of post-glacial spread into northern Europe. Despite the overall northwards decrease in diversity, the widespread occurrence of less common alleles and the lack of regional deviations from Hardy-Weinberg genotype frequency expectations suggest that C. arenaria is not predominantly self-fertilized.
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| 45. |
- Olsson, A, et al.
(författare)
-
Morphometric diversity and geographic differentiation in six dogrose taxa (Rosa Sect. Caninae, Rosaceae) from the Nordic countries
- 2001
-
Ingår i: Nordic Journal of Botany. - 0107-055X. ; 21:3, s. 225-241
-
Tidskriftsartikel (refereegranskat)abstract
- The dogroses (Rosa Sect. Caninae) are characterized by a unique meiosis - the canina meiosis - that results in restricted recombination. In the present study, we investigate population differentiation and morphometric diversity within six taxa, of Nordic dogroses, with the help of automated image analysis of leaflet shape and manually-measured reproductive characters. The total morphometric diversity in each character type was partitioned into its hierarchical components. The within-taxon structure of diversity in leaflet shape is similar (in both rank and magnitude) to the within-taxon structure of reproductive character diversity in all the taxa, with the between-population component of diversity accounting for the majority of the total diversity. The within-taxon structuring of diversity in the dogroses is comparable to that found in selfers and in species characterized by restricted recombination (such as permanent translocation heterozygotes). The relatively high within- and between-family components of diversity in R. dumalis subsp. dumalis may be a reflection of a heterogeneous genome and/or of a higher degree of outcrossing than in the other dogrose taxa. Rosa rubiginosa is characterized by low overall levels of intraspecific variation. There is weak geographic differentiation between populations of R. dumalis subsp. dumalis (in leaflet shape) and R. rubiginosa (in reproductive characters). The study provides no support for the division of R. dumalis into subsp. dumalis and subsp. coriifolia but, in contrast, shows a clear separation between varieties umbelliflora and venusta within R. sherardii.
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| 46. |
- Olsson, Åsa, et al.
(författare)
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Relationships between Nordic dogroses (Rosa L. sect. Caninae, Rosaceae) assessed by RAPDs and elliptic Fourier analysis of leaflet shape
- 2000
-
Ingår i: Systematic Botany. - 0363-6445. ; 25:3, s. 511-521
-
Tidskriftsartikel (refereegranskat)abstract
- The taxonomy of the dogroses (Rosa sect. Caninae) is notoriously problematic and all the members of the section are characterized by a form of unbalanced meiosis (so-called "canina meiosis"). We used a novel combination of random amplified polymorphic DNA (RAPD) markers and elliptic Fourier analysis of leaflet shape to investigate relationships within and between the seven common dogrose tara in the Nordic countries. A between-individual genetic distance matrix calculated on the basis of the presence/absence of RAPD hands was used in a non-metric multidimensional scaling analysis. Population data from elliptic Fourier analysis of leaflet shape were analyzed with canonical variates analysis. Elliptic Fourier analysis of leaflet shape provided a valuable complement to traditional, often subjectively-assessed, morphological characters and detected subtle patterns of within- and between-taxon differentiation that are generally consistent with the relationships recognized in the current taxonomic treatments of the section. In contrast, RAPDs emphasize the discontinuities between three groups of taxa and suggest that R. canina and the two subspecies of X. dumalis, as well as the taxon-pair A, sherardii and X. villosa subsp. mollis, are more closely related than can be concluded on the basis of morphological characters.
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| 47. |
- Pettorelli, Nathalie, et al.
(författare)
-
Time to integrate global climate change and biodiversity science-policy agendas
- 2021
-
Ingår i: Journal of Applied Ecology. - : Wiley. - 0021-8901 .- 1365-2664. ; 58:11, s. 2384-2393
-
Tidskriftsartikel (refereegranskat)abstract
- There is an increasing recognition that, although the climate change and biodiversity crises are fundamentally connected, they have been primarily addressed independently and a more integrated global approach is essential to tackle these two global challenges. Nature-based Solutions (NbS) are hailed as a pathway for promoting synergies between the climate change and biodiversity agendas. There are, however, uncertainties and difficulties associated with the implementation of NbS, while the evidence regarding their benefits for biodiversity remains limited. We identify five key research areas where incomplete or poor information hinders the development of integrated biodiversity and climate solutions. These relate to refining our understanding of how climate change mitigation and adaptation approaches benefit biodiversity conservation; enhancing our ability to track and predict ecosystems on the move and/or facing collapse; improving our capacity to predict the impacts of climate change on the effectiveness of NbS; developing solutions that match the temporal, spatial and functional scale of the challenges; and developing a comprehensive and practical framework for assessing, and mitigating against, the risks posed by the implementation of NbS. Policy implications. The Conference of the Parties (COP) for the United Nations Framework Convention on Climate Change (COP26) and the Convention on Biological Diversity (COP15) present a clear policy window for developing coherent policy frameworks that align targets across the nexus of biodiversity and climate change. This window should (a) address the substantial and chronic underfunding of global biodiversity conservation, (b) remove financial incentives that negatively impact biodiversity and/or climate change, (c) develop higher levels of integration between the biodiversity and climate change agendas, (d) agree on a monitoring framework that enables the standardised quantification and comparison of biodiversity gains associated with NbS across ecosystems and over time and (e) rethink environmental legislation to better support biodiversity conservation in times of rapid climatic change.
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| 48. |
- Prentice, Honor C, et al.
(författare)
-
A horizontally transferred nuclear gene is associated with microhabitat variation in a natural plant population.
- 2015
-
Ingår i: Royal Society of London. Proceedings B. Biological Sciences. - : The Royal Society. - 1471-2954 .- 0962-8452. ; 282:1821
-
Tidskriftsartikel (refereegranskat)abstract
- Horizontal gene transfer involves the non-sexual interspecific transmission of genetic material. Even if they are initially functional, horizontally transferred genes are expected to deteriorate into non-expressed pseudogenes, unless they become adaptively relevant in the recipient organism. However, little is known about the distributions of natural transgenes within wild species or the adaptive significance of natural transgenes within wild populations. Here, we examine the distribution of a natural plant-to-plant nuclear transgene in relation to environmental variation within a wild population. Festuca ovina is polymorphic for an extra (second) expressed copy of the nuclear gene (PgiC) encoding cytosolic phosphoglucose isomerase, with the extra PgiC locus having been acquired horizontally from the distantly related grass genus Poa. We investigated variation at PgiC in samples of F. ovina from a fine-scale, repeating patchwork of grassland microhabitats, replicated within spatially separated sites. Even after accounting for spatial effects, the distributions of F. ovina individuals carrying the additional PgiC locus, and one of the enzyme products encoded by the locus, are significantly associated with fine-scale habitat variation. Our results suggest that the PgiC transgene contributes, together with the unlinked 'native' PgiC locus, to local adaptation to a fine-scale mosaic of edaphic and biotic grassland microhabitats.
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| 49. |
- Prentice, Honor C, et al.
(författare)
-
Allozyme and chloroplast DNA variation in island and mainland populations of the rare Spanish endemic, Silene hifacensis (Caryophyllaceae)
- 2003
-
Ingår i: Conservation Genetics. - 1566-0621. ; 4:5, s. 543-555
-
Tidskriftsartikel (refereegranskat)abstract
- Silene hifacensis is a narrowly endemic plant, restricted to a few small populations on limestone cliffs in the Spanish province of Alicante and on the Balearic island of Ibiza. The species was collected to extinction in its original mainland location by the early 20th century. Attempts have been made to reintroduce S. hifacensis to this area but conservation efforts are limited by a lack of information on the geographic structure of genetic variation in the species. We used nuclear (allozyme) and chloroplast DNA (cpDNA) PCR/RFLP markers to investigate the structure of genetic variation in 2 mainland and 6 Ibizan populations. Levels of allozyme variation were low, with a mean of 2 alleles per polymorphic locus. Mean (over polymorphic loci) total allozyme diversity (H-tot) was 0.203 and mean within-population diversity (H-pop) was 0.085. Most diversity was explained by the between-population diversity component (G(pop).reg = 57%). Both mainland populations showed allozyme fixation. Three composite cpDNA haplotypes were identified. The first is unique to a mainland population that is also allozymically distinct from all the other populations. The second haplotype is found in the other mainland population and one Ibizan population: these two populations are allozymically identical. The remaining Ibizan populations contain the third haplotype. The geographic distribution of allozymes and cpDNA haplotypes is discussed in terms of population history, dispersal and, speculatively, in terms of the possibility that there has been undocumented translocation of material between populations.
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- Prentice, Honor C, et al.
(författare)
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Changes in allozyme frequencies in Festuca ovina populations after a 9-year nutrient/water experiment
- 2000
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Ingår i: Journal of Ecology. - : Wiley. - 0022-0477 .- 1365-2745. ; 88:2, s. 331-347
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Tidskriftsartikel (refereegranskat)abstract
- 1 The grass Festuca ovina is an important constituent of the species-rich 'alvar' grasslands on the Baltic island of Oland. Levels of allozyme polymorphism are high and variation is known to be correlated with habitat variation (soil moisture, pH and depth). 2 A 9-year field experiment on species diversity provided replicate plots (in three sites) that had been subjected to six different experimental treatments (control; N + P + K; P + K; N + K; K; water). 3 Samples of F. ovina were collected and analyses of deviance were used to investigate associations between allele frequencies, at each of four polymorphic loci, and the nutrient/water treatments. We also used the models to estimate predicted values for the alleles in different nutrient/water treatments and in interactions involving the nutrient/water treatments and additional explanatory variables (vegetation height and clipping). 4 There were significant allozyme frequency differences between samples of F. ovina from the six different nutrient/water treatments in the grassland experiment. Frequencies in the fertilized or watered plots had diverged from those in the control plots. There were also significant allele-habitat associations (after the removal of site effects), especially at the Pgi-2 locus. 5 Soil moisture was the only variable that was common to this study and an earlier study of variation in F. ovina in natural habitats. In natural populations, the Pgi-2-2 allele was significantly associated with soil moisture and was more common in dry habitats. Our findings that the frequency of the Pgi-2-2 allele was significantly affected by the nutrient/water treatments, and that it was rarest in the treatment that involved the addition of extra water, were therefore as predicted. 6 The study supports the conclusion, from an earlier study of populations in unmanipulated grassland habitats, that selection is contributing to the fine-scale patterning of genetic variation in the alvar populations of F. ovina.
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