Phylogenetic and functional distinctiveness explain alien plant population responses to competition.

Several invasion hypotheses predict a positive association between phylogenetic and functional distinctiveness of aliens and their performance, leading to the idea that distinct aliens compete less with their resident communities. However, synthetic pattern relationships between distinctiveness and alien performance and direct tests of competition as the driving mechanism have not been forthcoming. This is likely because different patterns are observed at different spatial grains, because functional trait and phylogenetic information are often incomplete, and because of the need for competition experiments that measure demographic responses across a variety of alien species that vary in their distinctiveness.

Reduction of urban traffic-related particulate matter-leaf trait matters.

Particulate matter in European cities, especially in urban areas, is mainly from urban road traffic and constitutes a great threat to the health of inhabitants. Therefore, understanding of the role of common urban roadside plant plays for particulate matter (PM) reduction would have important meaning for the mitigation of urban air pollution. The leaf surface PM capturing capacity of 12 representative urban plants (five shrubs and seven trees) alongside one main street in Hanover Germany was explored in this study.

Glacial refugia and speciation in a group of wind-pollinated and -dispersed, endemic Alpine species of Helictotrichon (Poaceae).

In the Alps phylogeographic studies indicate for small insect-pollinated herbs that climatic fluctuations caused significant population migrations and fragmentations into glacial refugia at the periphery of the Alps. Here we investigate whether this holds also for wind-pollinated and -dispersed species. We therefore analysed the phylogeographic pattern (nuclear and chloroplast dataset) of a clade of the four species of the Helictotrichon parlatorei species group (Poaceae) endemic to the Alps.

Ecosystem functions including soil organic carbon, total nitrogen and available potassium are crucial for vegetation recovery.

The effects of biodiversity on ecosystem functions have been extensively studied, but little is known about the effects of ecosystem functions on biodiversity. This knowledge is important for understanding biodiversity-ecosystem functioning relationships. Desertification reversal is a significant global challenge, but the factors that play key roles in this process remain unclear.

Genetic structure of Galitzkya macrocarpa and G. potaninii, two closely related endemics of central Asian mountain ranges.

Unlabelled: BACKGROUND AND AIMS Habitats in mountains are often isolated. Plants growing in these sites face severe dispersal limitations, but also difficulties for recruitment. The focus was laid on the magnitude of genetic differences among populations but also on the size of potentially occurring clones.

Species groups can be transferred across different scales.

To test whether species groups (i.e. assemblages of species co-occurring in nature) that are statistically derived at one scale (broad, medium, or fine scale) can be transferred to another scale, and to identify the driving forces that determine species groups at the various scales.

Evolution of the realized climatic niche in the genus Arabidopsis (Brassicaceae).

The evolution of the realized climatic niche in the genus Arabidopsis was studied using an almost complete phylogenetic tree based on DNA sequences of the ribosomal internal transcribed spacers. The realized climatic niche (climate space) was determined by the intersections of the distribution ranges of the taxa with climate data and is presented in temperature/precipitation diagrams. A positive correlation exists between the climate spaces of the taxa and their range sizes.

Effects of range position, inter-annual variation and density on demographic transition rates of Hornungia petraea populations.

The central-marginal model assumes unfavourable and more variable environmental conditions at the periphery of a species' distribution range to negatively affect demographic transition rates, finally resulting in reduced population sizes and densities. Previous studies on density-dependence as a crucial factor regulating plant population growth have mainly focussed on fecundity and survival. Our objective is to analyse density-dependence in combination with the effect of inter-annual variation and range position on all life stages of an annual plant species, Hornungia petraea, including germination and seed incorporation into the seed bank.

An ecological 'footprint' of climate change.

Recently, there has been increasing evidence of species' range shifts due to changes in climate. Whereas most of these shifts relate ground truth biogeographic data to a general warming trend in regional or global climate data, we here present a reanalysis of both biogeographic and bioclimatic data of equal spatio-temporal resolution, covering a time span of more than 50 years. Our results reveal a coherent and synchronous shift in both species' distribution and climate.

The impact of altitude and simulated herbivory on the growth and carbohydrate storage of Petasites albus.

We tested the hypothesis that higher respiratory losses caused by higher temperatures in the lowlands, compared to montane sites, prevent growth of the montane hemicryptophyte Petasites albus (Asteraceae). In addition, we tested whether increased levels of herbivory enhanced carbon losses at lower elevations. Rhizomes of Petasites albus were transplanted to a montane and a lowland site.

Ecological responses to recent climate change.

There is now ample evidence of the ecological impacts of recent climate change, from polar terrestrial to tropical marine environments. The responses of both flora and fauna span an array of ecosystems and organizational hierarchies, from the species to the community levels. Despite continued uncertainty as to community and ecosystem trajectories under global change, our review exposes a coherent pattern of ecological change across systems.

Molecular diversity and physical mapping of 5S rDNA in wild and cultivated oat grasses (Poaceae: Aveneae).

5S rDNA repeats studied in five genera of Aveneae have lengths between 285 and 329 bp (Avena sativa, Avena macrostachya, 26 species of Helictotrichon, Pseudarrhenatherum longifolium, Lagurus ovatus, and Trisetum spicatum). In only a single species (Helictotrichon aetolicum) an additional repeat of 456 bp occurs infrequently. Variation is largely due to insertions or deletions in the nontranscribed spacer as determined from sequences of 163 independent clones.