1,721,071 research outputs found
Plant functional traits and diversity in sand dune ecosystems across different biogeographic regions
No full textPlant species of a functional group respond similarly to environmental pressures and may be expected to act similarly on ecosystem processes and habitat properties. However, feasibility and applicability of functional groups in ecosystems across very different climatic regions have not yet been studied. In our approach we specified the functional groups in sand dune ecosystems of the Mediterranean, Hyrcanian and Irano-Turanian phytogeographic regions. We examined whether functional groups are more influenced by region or rather by habitat characteristics, and identified trait syndromes associated with common habitat types in sand dunes (mobile dunes, stabilized dunes, salt marshes, semi-wet sands, disturbed habitats). A database of 14 traits, 309 species and 314 releves was examined and trait-species, trait-plot and species-plot matrices were built. Cluster analysis revealed similar plant functional groups in sand dune ecosystems across regions of very different species composition and climate. Specifically, our study showed that plant traits in sand dune ecosystems are grouped reflecting habitat affiliation rather than region and species pool. Environmental factors and constraints such as sand mobility, soil salinity, water availability, nutrient status and disturbance are more important for the occurrence and distribution of plant functional groups than regional belonging. Each habitat is shown to be equipped with specific functional groups and can be described by specific sets of traits. In restoration ecology the completeness of functional groups and traits in a site may serve as a guideline for maintaining or restoring the habitat. (C) 2016 Elsevier Masson SAS. All rights reserved.Reinhold-und-Johanna-Tuxen-Stiftung Ira
Identifying plant communities of thermophilous deciduous forest in Greece: Species composition, distribution, ecology and syntaxonomy
No full textThermophilous deciduous forest is widespread in northern mainland Greece and extends in patches further south to Peloponnisos and the bigger islands. In this paper, we provide a phytosociological survey of the plant communities of deciduous oak and mixed forest throughout Greece, based on about 370 releves from the literature and more than 300 personal unpublished ones. Assocation names of the thermophilous deciduous forest are re-evaluated, and syntaxonomic conclusions added. The releves are classified, and 13 associations and several additional subtypes described and presented in synoptic constancy tables. The following associations were recognized, and characterized by species composition, ecology and distribution: 1. Phillyreo-Carpinetum orientalis, 2. Dryopterido pallidae-Ostryetum carpinifoliae, 3. Tilio tomentosae-Castanetum; 4. Genisto carinalis-Quercetum petraeae, 5. Querco frainetto-Castanetum, 6. Cytiso villosi-Castanetum; 7. Lathyro laxiflori-Castanetum; 8. Symphyto ottomani-Quercetum frainetto, 9. Verbasco glabrati-Quercetum frainetto; 10. Huetio cynapioidis-Quercetum frainetto; 11. Digitali viridiflorae-Quercetum frainetto; 12. Geranio asphodeloidis-Quercetum frainetto; 13. Oenantho pimpinelloidis-Quercetum frainetto. Associations 1-2 are assigned to the alliance Fraxino orni-Ostryion, 4-6 and 8-13 to the Quercion frainetto (both Quercetalia pubescentis), 3 interim to the Tilio-Acerion, and 7 to the Quercetalia ilicis. The two Quercetalia pubescentis alliances co-occur in northern Greece; their habitats differ chiefly in terms of soil conditions, bedrock and topography, rather than in overall climatic character
Arzneipflanzenflora im ehemaligen Königreich Hannover laut G.F.W. Meyer (Stand: 1836–1849) und heute
No full textReciprocal extrapolation of species distribution models between two islands – Specialists perform better than generalists and geological data reduces prediction accuracy
No full textThis study aims to test the extrapolation effects of species distribution models (SDM) using three groups of predictor variables: climate, relief and geology (bedrock type). We highlight potential ecological differences for selected taxa, regarding both generalists and specialists in terms of edaphic conditions. We used distributional data of 12 woody species shared by two large Mediterranean islands (Crete and Sicily) to calibrate Maxent models of their potential distribution. We trained models with data from Crete and extrapolated to Sicily and vice versa. We tested ten proxies for the three variable groups and compared AUC values as a measure of model performance. Extrapolation of SDMs worked fairly well across species and islands for those models including climatic and relief data, while those including geological information performed worse for the tested species. Edaphic generalists performed less well compared to edaphic specialists. The latter performed best with climate data included in models and more poorly with only geological data. This may be due to differences in bedrock type affinities of species between the two islands
Effektivität der Förderprogramme für Ackerwildkräuter in Südniedersachsen seit den 1980er-Jahren
No full textEffektivität der Förderprogramme für Ackerwildkräuter in Südniedersachsen seit den 1980er-Jahren
No full text
The diversity of woodland vegetation in Central Albania along an altitudinal gradient of 1300 m
No full textThe woodland vegetation of Central Albania is studied and discussed along an altitudinal gradient in the Dajti National Park (DNP). The plant species combinations recorded in 168 plots were classified and subjected to indirect gradient analysis using environmental variables of geology, soil, topography, disturbance and grazing impact. The transect over more than 1300 m reflects the biogeographically intermediate paramediterranean vegetation zonation and the relatively humid Mediterranean "hygric series" at its eastern margins. It reveals the total range of woodland types known to occur in Central Albania, thus stressing the representativity of the area regarding biodiversity and biogeography, and its importance for nature conservation. Along the elevation gradient, we found three plant communities of the mesomediterranean Quercetalia ilicis, five of the supramediterranean Quercetalia pubescentis and five of the montane or oromediterranean Fagetalia sylvaticae.DAA
- …
