Floristic evidence for alternative biome states in tropical Africa.

Autor:	Aleman JC; Gembloux Agro-Bio Tech, Université de Liège, 5030 Gembloux, Belgium.; Département de Géographie, Université de Montréal, Montréal, QC H2V 0B3, Canada., Fayolle A; Gembloux Agro-Bio Tech, Université de Liège, 5030 Gembloux, Belgium; adeline.fayolle@uliege.be., Favier C; Institut des Sciences de l'Evolution-Montpellier, CNRS, Ecole Pratique des Hautes Etudes, Institut de Recherche pour le Développement, Université de Montpellier, 34000 Montpellier, France., Staver AC; Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06520., Dexter KG; School of GeoSciences, University of Edinburgh, EH8 9YL Edinburgh, United Kingdom.; Tropical Diversity Section, Royal Botanic Garden Edinburgh, EH3 5LR Edinburgh, United Kingdom., Ryan CM; School of GeoSciences, University of Edinburgh, EH8 9YL Edinburgh, United Kingdom., Azihou AF; Laboratory of Applied Ecology, Faculty of Agronomic Sciences, University of Abomey-Calavi, 01 BP 526 Cotonou, Benin., Bauman D; Environmental Change Institute, School of Geography and the Environment, University of Oxford, OX1 3QY Oxford, United Kingdom.; Plant Ecology and Biogeochemistry, Université Libre de Bruxelles, 1050 Bruxelles, Belgium., Te Beest M; Copernicus Institute of Sustainable Development, Utrecht University, 3584 CS Utrecht, The Netherlands.; Centre for African Conservation Ecology, Nelson Mandela University, 6031 Port Elizabeth, South Africa.; Grasslands-Forests-Wetlands Node, South African Environmental Observation Network, 3201 Pietermaritzburg, South Africa., Chidumayo EN; Makeni Savanna Research Project, Ridgeway, 1001 Lusaka, Zambia., Comiskey JA; Inventory and Monitoring Program, National Park Service, Fredericksburg, VA 22405.; Smithsonian Institution, Washington, DC 20002., Cromsigt JPGM; Copernicus Institute of Sustainable Development, Utrecht University, 3584 CS Utrecht, The Netherlands.; Centre for African Conservation Ecology, Nelson Mandela University, 6031 Port Elizabeth, South Africa.; Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden., Dessard H; Forêts et Sociétés, Centre de Coopération Internationale en Recherche Agronomique Pour le Développement, Université de Montpellier, 34000 Montpellier, France.; Centre de Coopération Internationale en Recherche Agronomique Pour le Développement, Forêts et Sociétés, 34398 Montpellier, France., Doucet JL; Gembloux Agro-Bio Tech, Université de Liège, 5030 Gembloux, Belgium., Finckh M; Biodiversity, Evolution and Ecology of Plants, Institute of Plant Science and Microbiology, University of Hamburg, 22609 Hamburg, Germany., Gillet JF; Gembloux Agro-Bio Tech, Université de Liège, 5030 Gembloux, Belgium., Gourlet-Fleury S; Forêts et Sociétés, Centre de Coopération Internationale en Recherche Agronomique Pour le Développement, Université de Montpellier, 34000 Montpellier, France.; Centre de Coopération Internationale en Recherche Agronomique Pour le Développement, Forêts et Sociétés, 34398 Montpellier, France., Hempson GP; Centre for African Ecology, School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, 2000 Johannesburg, South Africa., Holdo RM; Odum School of Ecology, University of Georgia, Athens, GA 30602., Kirunda B; Wildlife Conservation Society, Kampala, Uganda., Kouame FN; Nature Sciences Unit, University Nangui Abrogoua, 31 BP 165 Abidjan, Côte d'Ivoire., Mahy G; Gembloux Agro-Bio Tech, Université de Liège, 5030 Gembloux, Belgium., Gonçalves FMP; Herbário do Lubango, Instituto Superior de Ciências da Educação da Huíla, C.P. 230 Lubango, Angola., McNicol I; School of GeoSciences, University of Edinburgh, EH8 9YL Edinburgh, United Kingdom., Quintano PN; School of GeoSciences, University of Edinburgh, EH8 9YL Edinburgh, United Kingdom., Plumptre AJ; Wildlife Conservation Society, Kampala, Uganda.; Head Key Biodiversity Area Secretariat, c/c BirdLife International, CB2 3QZ Cambridge, United Kingdom.; Conservation Science Group, Zoology Department, Cambridge University, CB2 3EJ Cambridge, United Kingdom., Pritchard RC; School of GeoSciences, University of Edinburgh, EH8 9YL Edinburgh, United Kingdom.; Global Development Institute, University of Manchester, M13 9PL Manchester, United Kingdom., Revermann R; Biodiversity, Evolution and Ecology of Plants, Institute of Plant Science and Microbiology, University of Hamburg, 22609 Hamburg, Germany.; Faculty of Natural Resources and Spatial Sciences, Namibia University of Science and Technology, Windhoek, Namibia., Schmitt CB; Center for Development Research, University of Bonn, 53113 Bonn, Germany.; Nature Conservation and Landscape Ecology, University of Freiburg, 79106 Freiburg, Germany., Swemmer AM; South African Environmental Observation Network, SAEON Ndlovu Node, Phalaborwa, 1390, South Africa., Talila H; Department of Ecotourism and Biodiversity Conservation, College of Agriculture and Natural Resource, Madda Walabu University, Bale Robe, Ethiopia., Woollen E; School of GeoSciences, University of Edinburgh, EH8 9YL Edinburgh, United Kingdom., Swaine MD; Institute of Biological and Environmental Sciences, University of Aberdeen, AB24 3FX Aberdeen, United Kingdom.
Jazyk:	angličtina
Zdroj:	Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2020 Nov 10; Vol. 117 (45), pp. 28183-28190. Date of Electronic Publication: 2020 Oct 27.
DOI:	10.1073/pnas.2011515117
Abstrakt:	The idea that tropical forest and savanna are alternative states is crucial to how we manage these biomes and predict their future under global change. Large-scale empirical evidence for alternative stable states is limited, however, and comes mostly from the multimodal distribution of structural aspects of vegetation. These approaches have been criticized, as structure alone cannot separate out wetter savannas from drier forests for example, and there are also technical challenges to mapping vegetation structure in unbiased ways. Here, we develop an alternative approach to delimit the climatic envelope of the two biomes in Africa using tree species lists gathered for a large number of forest and savanna sites distributed across the continent. Our analyses confirm extensive climatic overlap of forest and savanna, supporting the alternative stable states hypothesis for Africa, and this result is corroborated by paleoecological evidence. Further, we find the two biomes to have highly divergent tree species compositions and to represent alternative compositional states. This allowed us to classify tree species as forest vs. savanna specialists, with some generalist species that span both biomes. In conjunction with georeferenced herbarium records, we mapped the forest and savanna distributions across Africa and quantified their environmental limits, which are primarily related to precipitation and seasonality, with a secondary contribution of fire. These results are important for the ongoing efforts to restore African ecosystems, which depend on accurate biome maps to set appropriate targets for the restored states but also provide empirical evidence for broad-scale bistability. Competing Interests: The authors declare no competing interest.
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu