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Rare fish species in European lakes – patterns and processesNARA Subscribed
According to differences in life history and species niches, community assembly processes are predicted to differ between common and rare species. While neutral processes, in particular dispersal, should contribute strongly to assembly of rare species, environmental filtering (species sorting) should dominate the community assembly of common species. We analysed commonness and rarity by occurrence, abundance and geographic ran...
Are global forests performing in sync? The need to account for spatiotemporal biases in tree‐ring recordsNARA Subscribed
Populations whose dynamics are driven by correlated environmental stochasticity face increased risk of extinction. Forests in particular are being pushed to their physiological limits under global change; hence, the analysis of common patterns of tree performance across scales becomes crucial to discern early warning signals and tipping points. Here, we critically evaluate customary and recent approaches for the analysis of ti...
Aim We tested whether there is a strong effect of species interactions on assembly of local lake fish communities, in addition to environmental filters and dispersal. Location Seven hundred and seventy‐two European lakes and reservoirs. Time period 1993–2012. Major taxa studied Nineteen species of freshwater fishes. Methods We applied a latent variable approach using Bayesian Markov chain Monte Carlo algorithms (R package “BOR...
Climate warming can restructure lake food webs if trophic levels differ in their thermal responses, but evidence for these changes and their underlying mechanisms remain scarce in nature. Here we document how warming lake temperatures by up to 2°C, rather than changes in trophic state or fishing effort, have restructured the pelagic food web of a large European lake (Lake Maggiore, Italy). Our approach exploited abundance and...
Fish community feeding and production rates may differ between lakes despite similar fish biomass levels because of differences in size structure and local temperature. Therefore, across‐lake comparisons of the strength and direction of top‐down and bottom‐up fish–phytoplankton relationships should consider these factors. We used the metabolic theory of ecology to calculate size‐ and temperature‐corrected community energy dema...
Spatio‐temporal patterns of tree growth as related to carbon isotope fractionation in European forests under changing climateNARA Subscribed
Aim The aim was to decipher Europe‐wide spatio‐temporal patterns of forest growth dynamics and their associations with carbon isotope fractionation processes inferred from tree rings as modulated by climate warming. Location Europe and North Africa (30‒70° N, 10° W‒35° E). Time period 1901‒2003. Major taxa studied Temperate and Euro‐Siberian trees. Methods We characterize changes in the relationship between tree growth and car...
Geographical patterns in the body‐size structure of European lake fish assemblages along abiotic and biotic gradientsNARA Subscribed
Aim Our aim was to document geographical patterns of variation in the body‐size structure of European lake fish assemblages along abiotic gradients, and any differences in fish assemblage structure. We hypothesized that patterns in the body‐size structure of entire lake fish assemblages are primarily temperature driven and consistent with the dominant pattern of the temperature–size rule, which suggests a decrease in adult bod...
Precipitation has been of utmost importance in shaping the evolution of landscapes and human settlements in the Mediterranean. However, information on seasonal precipitation patterns through the Holocene is scarce. This study attempts to quantify the evolution of seasonal precipitation in the East Iberian Peninsula (5000 BC to AD 600) based on the carbon isotope composition (δ 13 C) of archaeobotanical remains. Data on Holm oa...
Carbon isotope composition of fossil charcoal reveals aridity changes in the NW Mediterranean BasinNARA Subscribed
Although several proxies for the inference of precipitation have been proposed, evidence of changes in aridity during the Holocene is scarce, and most is only qualitative. Moreover, precipitation regimes show relatively poor spatial correlations and can exhibit contrasting responses to global climate trends in different areas. Thus, there is a need to concentrate efforts at the local scale in order to increase the spatial reso...
The analysis of carbon isotope discrimination (Δ) in crop plant remains from archaeological sites may help to assess water availability for early agriculture. This study presents the analysis of Δ in seeds of naked wheat ( Triticum aestivum/durum ), lentil ( Lens orientalis/culinaris ), and flax ( Linum sp.) found at the archaeological site of Tell Halula in the valley of the Middle Euphrates (Syria). This Neolithic site is th...
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