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  • Author or Editor: J. Reif x
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Climatically induced shifts of species’ geographic ranges can provide important information about the potential future assembly of ecological communities. Surprisingly, interspecific variability in the magnitude and direction of these range shifts in birds has been the subject of few scientific studies, and a more detailed examination of species’ ecological traits related to this variability is needed. Using maps in the Climatic Atlas of European Breeding Birds (Huntley et al. 2007) we calculated the potential shifts of European breeding ranges in 298 bird species, and explored their relationships with breeding habitat, dietary niche, migration strategy, life history and geographic position of the current breeding range. Breeding habitat type showed the strongest relationship with the potential range shifts, with forest and wetland species showing the largest magnitude of shift. At the same time, ecological specialists showed a larger magnitude of shifts than generalists. In addition, we found that species with current ranges situated near continental borders and species with lower migratory capacity are more limited in their potential to shift due to climate change. Our analyses thus indicate which ecological groups of birds will be most likely forced to move their ranges under predicted climate change. This knowledge can help to adopt proper conservation actions. These actions will be particularly important in the case of specialist species, which have been shown to be the most sensitive to climate change impacts.

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It has been claimed that the system that delivers the products of plant breeding reduces the diversity of cultivated varieties, leading to increased genetic vulnerability. The objective of our study was to monitor the temporal trends in genetic diversity over the past five decades among maize cultivars with the largest acreage in Central Europe. Thirty individuals of five prominent open-pollinated varieties (OPVs) from Central Europe, 85 maize hybrids of economic importance, and their dent and flint parental components were examined with 55 SSRs. The genetic variation within and among varieties decreased significantly during the five decades. The five OPVs contain numerous unique alleles that were absent from the elite flint pool. Consequently, OPVs could represent useful sources for broadening the genetic base of elite maize breeding germplasm.

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Today, native vegetation in the Valdivian Coastal Range (VCR) is restricted to areas where small-scale land use dominates resulting in a vegetation mosaic. This study (1) provides a description of the vegetation types (VT) within the vegetation mosaic, (2) identifies land use drivers that lead to either degradation or recovery processes and, (3) attempts to provide an explanation for the vegetation mosaic with a conceptual model. In two regions of the VCR we sampled 102 plots for composition of vegetation and indicators of livestock browsing, timber cutting and coppice forestry. We classified the vegetation using a flexible beta method and Bray-Curtis distance. Diagnostic species were identified by an extended indicator species analysis. The clustering results were visualized in NMDS and recursive partitioning was used to explain variations in the VTs as a function of the land use variables. Differentiating effects were tested using PERMANOVA and a conceptual model for the vegetation dynamics was developed from the results. Four VTs such as (1) extensively grazed non-native grasslands (EGN); (2), closed and semi-closed grazed Ugni and Berberis shrublands; (3) severely impacted evergreen forests; and (4) sparsely disturbed evergreen forests were recognized. The browsing indicators were important for differentiating the VTs. The EGN grasslands were differentiated by having more than 0.075 dung piles/m2. Areas with fewer dung piles but direct browsing effects had the greatest impact on vegetation. Forests were preserved when the mean browsing index was equal to or lower than 0.5. The cutting frequency was significant in determining overall floristic composition. We showed that shrublands and evergreen forests within the vegetation mosaic and the result of small-scale farming led to high native forest species richness. This makes the vegetation mosaic especially valuable in a landscape dominated by exotic tree monocultures.

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The optimum allocation of breeding resources is crucial for the efficiency of breeding programmes. The objectives were to (i) compare selection gain ΔG k for finite and infinite sample sizes, (ii) compare ΔG k and the probability of identifying superior hybrids (P k), and (iii) determine the optimum allocation of the number of hybrids and test locations in hybrid maize breeding using doubled haploids. Infinite compared to finite sample sizes led to almost identical optimum allocation of test resources, but to an inflation of ΔG k. This inflation decreased as the budget and the number of finally selected hybrids increased. A reasonable P k was reached for hybrids belonging to the q = 1% best of the population. The optimum allocations for P k (q) and ΔG k were similar, indicating that P k (q) is promising for optimizing breeding programmes.

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