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Biodiversity conservation in cities: Defining habitat analogues for plant species of conservation interest / M. Itani in Plos one, vol 15 n° 6 (June 2020)
Titre : Biodiversity conservation in cities: Defining habitat analogues for plant species of conservation interest Type de document : Article/Communication Auteurs : M. Itani, Auteur Année de publication : 2020 Article en page(s) : n° 0220355 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Ecologie
[Termes IGN] Beyrouth
[Termes IGN] conservation de la flore
[Termes IGN] espèce exotique envahissante
[Termes IGN] habitat (nature)
[Termes IGN] habitat d'espèce
[Termes IGN] Matthiola (genre)
[Termes IGN] TWINSPAN
Résumé : (auteur) Urban green spaces, both unmanaged and managed, include novel ecosystems that may be suitable habitat analogues for native plant species of conservation interest. The objective of this study was to define habitat analogues in the Mediterranean city of Beirut for Matthiola crassifolia, a Lebanese steno-endemic only present in urban habitats. We adopted a stepwise method that integrates two vegetation assessments, floristics, and life form. We placed seventy-eight quadrats (1m x 1m) in 12 study sites following a deliberate biased approach to capture habitat diversity. In every quadrat, we performed taxonomic identification and recorded life forms of each species. We pooled species that shared the same life form and estimated area cover for each life form accordingly. We performed TWINSPAN analyses on both floristic and life form data, then combined these findings to generate a description of habitat analogues suitable for M. crassifolia. TWINSPAN analysis of floristic data clustered the 78 quadrats under 17 quadrat groups, while life form data assembled the quadrats under 11 quadrat groups. The integration of floristic and life-form classification results into one matrix generated 30 quadrat groups, 8, which were highly favorable to M. crassifolia, and 12, which excluded it. The stepwise method unveiled similarities between vegetation assemblages, which appeared distinct due to the high presence of ruderals. We found that habitat analogues favorable to M. crassifolia include green spaces dominated by palms, low-lying succulents, or shrubs with scale-like leaves. In contrast, areas dominated by turf grass, canopy trees, or vegetation that produces significant litter were not favorable to M. crassifolia’s persistence. Based on these findings, we generated a plant palette of life forms which guides designs of urban habitats favorable to M. crassifolia. Numéro de notice : A2020-831 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article DOI : 10.1371/journal.pone.0220355 date de publication en ligne : 09/06/2020 En ligne : https://doi.org/10.1371/journal.pone.0220355 Format de la ressource électronique : URL article Permalink :
in Plos one > vol 15 n° 6 (June 2020) . - n° 0220355[article]Classification of European beech forests: a Gordian Knot? / Wolfgang Willner in Applied Vegetation Science, vol 20 n° 3 (July 2017)
Titre : Classification of European beech forests: a Gordian Knot? Type de document : Article/Communication Auteurs : Wolfgang Willner, Auteur ; Borja Jimenez-Alfaro, Auteur ; Emiliano Agrillo, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 494 - 512 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Asie mineure
[Termes IGN] Europe (géographie politique)
[Termes IGN] Fagus orientalis
[Termes IGN] Fagus sylvatica
[Termes IGN] phytosociologie
[Termes IGN] Turquie
[Termes IGN] TWINSPAN
[Termes IGN] unité phytosociologique
[Vedettes matières IGN] Ecologie forestière
Résumé : (auteur) Questions : What are the main floristic patterns in European beech forests? Which classification at the alliance and suballiance level is the most convincing?
Location : Europe and Asia Minor.
Methods : We applied a TWINSPAN classification to a data set of 24 605 relevés covering the whole range of Fagus sylvatica forests and the western part of Fagus orientalis forests. We identified 24 ‘operational phytosociological units’ (OPUs), which were used for further analysis. The position of each OPU along the soil pH and temperature gradient was evaluated using Ellenberg Indicator Values. Fidelity of species to OPUs was calculated using the phi coefficient and constancy ratio. We compared alternative alliance concepts, corresponding to groups of OPUs, in terms of number and frequency of diagnostic species. We also established formal definitions for the various alliance concepts based on comparison of the total cover of the diagnostic species groups, and evaluated alternative geographical subdivisions of beech forests.
Results : The first and second division levels of TWINSPAN followed the temperature and soil pH gradients, while lower divisions were mainly geographical. We grouped the 22 OPUs of Fagus sylvatica forests into acidophytic, meso-basiphytic and thermo-basiphytic beech forests, and separated two OPUs of F. orientalis forests. However, a solution with only two ecologically defined alliances of F. sylvatica forests (acidophytic vs basiphytic) was clearly superior with regard to number and frequency of diagnostic species. In contrast, when comparing groupings with three to six geographical alliances of basiphytic beech forests, respectively, we did not find a strongly superior solution.
Conclusions : We propose to classify F. sylvatica forests into 15 suballiances – three acidophytic and 12 basiphytic ones. Separating these two groups at alliance or order level was clearly supported by our results. Concerning the grouping of the 12 basiphytic suballiances into ecological or geographical alliances, as advocated by many authors, we failed to find an optimal solution. Therefore, we propose a multi-dimensional classification of basiphytic beech forests, including both ecological and geographical groups as equally valid concepts which may be used alternatively depending on the purpose and context of the classification.
Numéro de notice : A2017-661 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1111/avsc.12299 En ligne : http://doi.org/10.1111/avsc.12299 Format de la ressource électronique : URL article Permalink :
in Applied Vegetation Science > vol 20 n° 3 (July 2017) . - pp 494 - 512[article]