Atmospheric pollen was investigated using the Lanzoni VPSS 2000 (Lanzoni, Bologna- Italy) device for 2 years between 2012 and 2013 in the Sarıkamış district of Kars province, one of the highest regions of Türkiye. A total of 37,909 pollen grains were collected: 15,298 pollen grains in 2012 and 22,611 pollen grains in 2013. Out of 43 identified taxa, 21 were arboreal, and 22 were non-arboreal. Pollen from arboreal plants accounted for 36.34% (13,778 pollen grains) of the total, while pollen from non-arboreal plants accounted for 63.56% (24,095 pollen grains). Additionally, 0.10% (36 pollen grains) belonged to unidentified pollen. The most frequent arboreal plant pollen in the Sarıkamış atmosphere were Pinaceae (29.79%), Cupressaceae/Taxaceae (2.54%), and Morus (1.30%). The main non-arboreal plant pollen in the atmosphere of Sarıkamış were Poaceae (44.60%), Artemisia (2.98%), Amaranthaceae (2.79%), Rumex (2.41%), Urticaceae (2.33%), Plantago (2.19%), and Boraginaceae (1.40%). The maximum pollen concentration was observed in June and was associated with the pollination of Pinaceae and Poaceae.

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Alpine wetlands on the Qinghai-Tibetan Plateau are undergoing degradation. However, little is known regarding the response of soil nematodes to this degradation. We conducted investigations in a wet meadow (WM), a grassland meadow (GM), a moderately degraded meadow (MDM) and a severely degraded meadow (SDM) from April to October 2011. The nematode community taxonomic composition was similar in the WM, GM and MDM and differed from that in the SDM. The abundance declined significantly from the WM to the SDM. The taxonomic richness and Shannon index were comparable between the WM and MDM but were significantly lower in the SDM, and the Pielou evenness showed the opposite pattern. The composition, abundance and diversity in the WM and SDM were relatively stable over time compared with other habitats. The abundances of all trophic groups, aside from predators, decreased with degradation. The relative abundances of herbivores, bacterivores, predators and fungivores were stable, while those of omnivores and algivores responded negatively to degradation. Changes in the nematode community were mainly driven by plant species richness and soil available N. Our results demonstrate that alpine wetland degradation significantly affects the soil nematode communities, suppressing but not shifting the main energy pathways through the soil nematode communities.

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QUESTIONS: Humans are altering land use and impacting grazing intensities worldwide in alpine and sub‐alpine grasslands, and functional diversity (FD) is a useful tool for predicting changes in these grassland communities and for improving biodiversity conservation. We asked: (1) how does functional richness (FRic) differ between the five predominant grassland types in Andorra (2) of these five grassland types, which plant communities are subject to high habitat filtering and which are driven primarily by competitive interactions; (3) are certain grassland communities more prone to degradation than others; and (4) how do grazing intensity and elevation influence variations in FD indices? LOCATIONS: Five types of sub‐alpine and alpine grassland communities dominated by Festuca airoides, F. eskia, F. gautieri, F. paniculata and Nardus stricta in Andorra, at various elevations and with differing grazing intensities within a grassland type. METHODS: We used multiple functional diversity indices and structural equation modelling (SEM) to determine how grazing intensity, elevation, species richness and productivity affect functional diversity in 222 vegetation transects. RESULTS: Both plant diversity and functional richness were higher at higher grazing intensities, with the highest values found in the F. gautieri and F. paniculata grasslands and lowest in the Nardus stricta, F. airoides and F. eskia grasslands. Habitat filtering was observed in F. airoides grasslands. There was a general tendency for higher competitive interactions among plants at higher elevations and/or when species diversity increased. None of the five grassland communities considered appears disturbed, and all present similar functional attributes between dominant species. CONCLUSIONS: Our results highlight the fact that grazing is an integral part of Andorran mountain grasslands, acting as a structural component and providing higher functional richness in the most grazed communities.

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Temperate montane grasslands and their unique biotas are declining worldwide as they are increasingly being invaded by forests. The origin and persistence of these landscapes have been the focus of such controversy that in many areas their conservation is in doubt. In the USA some biologists have largely dismissed the grass balds of the Southern Appalachians as human artifacts or anomalous and transitory elements of regional geography, worthy of only limited preservation efforts. On the basis of information from biogeography, community ecology, regional history and palaeontology and from consideration of two other montane grassland ecosystems-East Carpathian poloninas and Oregon Coast Range grass balds-we hypothesize that these landscapes are more widespread than was formerly recognized; they are, in many cases, natural and ancient and largely owe their origin and persistence to past climatic extremes and the activities of large mammalian herbivores.

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Background and aims The amount of DNA in an unreplicated gametic chromosome complement is known as the C-value and is a key biodiversity character of fundamental significance with many practical and predictive uses. Since 1976, Bennett and colleagues have assembled eight compilations of angiosperm C-values for reference purposes and subsequently these have been pooled into the Angiosperm DNA C-values Database (http://data.kew.org/cvalues/). Since the last compilation was published in 2005, a large amount of data on angiosperm genome size has been published. It is therefore timely to bring these data together into a ninth compilation of DNA amounts. Scope The present work lists DNA C-values for 2221 species from 151 original sources (including first values for 1860 species not listed in previous compilations). Combining these data with those published previously shows that C-values are now available for 6287 angiosperm species. Key findings Analysis of the dataset, which is by far the largest of the nine compilations published since 1976, shows that angiosperm C-values are now being generated at the highest rate since the first genome sizes were estimated in the 1950s. The compilation includes new record holders for the smallest (1C = 0·0648 pg in Genlisea margaretae) and largest (1C = 152·23 pg in Paris japonica) genome sizes so far reported, extending the range encountered in angiosperms to nearly 2400-fold. A review of progress in meeting targets set at the Plant Genome Size meetings shows that although representation for genera, geographical regions and some plant life forms (e.g. island floras and parasitic plants) has improved, progress to increase familial representation is still slow. In terms of technique it is now clear that flow cytometry is soon likely to become the only method available for plant genome size estimations. Fortunately, this has been accompanied by numerous careful studies to improve the quality of data generated using this technique (e.g. design of new buffers, increased awareness and understanding of problems caused by cytosolic inhibitors). It is also clear that although the speed of DNA sequencing continues to rise dramatically with the advent of next-generation and third-generation sequencing technologies, 'complete genome sequencing' projects are still unable to generate accurate plant genome size estimates.

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