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- Herben, T, et al.
(författare)
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Longterm spatial dynamics of Succisa pratensis in a changing rural landscape : linking dynamical modelling with historical maps
- 2006
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Ingår i: Journal of Ecology. - : Wiley-Blackwell. - 0022-0477 .- 1365-2745. ; 94:1, s. 131-143
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Tidskriftsartikel (refereegranskat)abstract
- We attempt to explain the current distribution of a long-lived perennial plant, Succisa pratensis, in a rural landscape in southern Sweden by linking its population biology with documented changes in the landscape, using a dynamical, spatially explicit model incorporating population dynamics and spatial spreading of the plant. Changes in the landscape were inferred from historical maps (1850 and 1900) and aerial photographs (1945 and 2001). We tested whether predictions for the current species distribution are affected by assumptions about its early 19th century distribution, to determine whether recent history and current processes are dominant, and how past landscape changes determine current distributions. Initial conditions influence predictions of current distribution, suggesting that the current distribution still partly reflects the distribution of the species in the early 19th century. A period of 150 years is too short for Succisa to have spread extensively if dispersal parameters are given realistic values. Simulations in which present-day land-use patterns were imposed at earlier dates showed that changes in landscape structure over the past 175 years also had a strong effect on the present-day habitat occupancy and population sizes of Succisa. The dominant process for Succisanow is extinction from marginal habitats. It is therefore likely that the (relatively) high present-day occupation patterns are still due to much larger areas having been available in the past rather than to successful dispersal. Although the species has responded to landscape changes, there is little evidence of population sizes reaching equilibrium. Our approach shows that the wealth of landscape information available from historical maps can be linked with data on population biology by means of dynamical models that can make predictions about species dynamics.
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- Klimes, A., et al.
(författare)
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The ecological drivers of growth form evolution in flowering plants
- 2022
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Ingår i: Journal of Ecology. - : Wiley. - 0022-0477 .- 1365-2745. ; 10:7, s. 1525-36
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Tidskriftsartikel (refereegranskat)abstract
- In flowering plants (angiosperms), the herbaceous habit has evolved repeatedly from the ancestral woody state and herbs evolved repeatedly back to woody plants. Yet, how common these transitions were and which ecological conditions promote the herbaceous habit is poorly known. Several hypotheses exist, postulating an advantage of the herbaceous growth form to better cope with frost, drought, fire and shade and in allowing a fast life strategy, but their evaluation has been hitherto limited and support equivocal. We aim to evaluate these hypotheses by testing the difference between woody plants and herbs for a set of variables related to these hypotheses. We compiled and integrated data for up to 21,581 species representing 359 families from public databases. We estimated the minimum number of evolutionary transitions between both growth forms. We assembled data on frost, drought, fire and shade tolerances, clonality and specific leaf area and we tested individual hypotheses by comparing herbaceous and woody angiosperm growth forms globally and within selected biomes and clades using phylogenetic comparative analyses. We found 1656 evolutionary transitions from woody towards herbaceous growth form and 2111 transitions in the opposite direction. In agreement with our expectations, herbs were more tolerant to frost and shade than woody plants and had higher specific leaf area. However, the growth forms did not differ in their fire tolerance and clonality. Furthermore, contrary to our expectation, woody plants were more drought tolerant than herbs. The majority of the differences were robust to the choice of biome or clade. Synthesis. Both herbaceous and woody habits evolved many times making the evolution of growth forms a well-replicated event and suggesting that conditions favourable for either of the growth forms emerge often and plants respond to them. Apart from standard explanation by low temperatures, the success of herbs was likely enabled also by biotic interactions-by their fast life strategy, which is beneficial in seasonal and early successional habitats, and by their ability to tolerate shade.
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- Muenzbergova, Z., et al.
(författare)
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Historical habitat connectivity affects current genetic structure in a grassland species
- 2013
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Ingår i: Plant Biology. - : Wiley. - 1435-8603 .- 1438-8677. ; 15:1, s. 195-202
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Tidskriftsartikel (refereegranskat)abstract
- Many recent studies have explored the effects of present and past landscape structure on species distribution and diversity. However, we know little about the effects of past landscape structure on distribution of genetic diversity within and between populations of a single species. Here we describe the relationship between present and past landscape structure (landscape connectivity and habitat size estimated from historical maps) and current genetic structure in a perennial herb, Succisa pratensis. We used allozymes as co-dominant markers to estimate genetic diversity and deviation from HardyWeinberg equilibrium in 31 populations distributed within a 5 km(2) agricultural landscape. The results showed that current genetic diversity of populations was related to habitat suitability, habitat age, habitat size and habitat connectivity in the past. The effects of habitat age and past connectivity on genetic diversity were in most cases also significant after taking the current landscape structure into account. Moreover, current genetic similarity between populations was affected by past connectivity after accounting for current landscape structure. In both cases, the oldest time layer (1850) was the most informative. Most populations showed heterozygote excess, indicating disequilibrium due to recent gene flow or selection against homozygotes. These results suggest that habitat age and past connectivity are important determinants of distribution of genetic diversity between populations at a scale of a few kilometres. Landscape history may significantly contribute to our understanding of distribution of current genetic structure within species and the genetic structure may be used to better understand landscape history, even at a small scale.
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