- Environmental conditions - Plant communities on inselbergs - Adaptive strategies

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1 Tropical rock outcrops (inselbergs): their importance as habitat islands Stefan Porembski, University of Rostock, Institute of Biosciences, Dept.. of Botany,, Wismarsche Str. 8, D Rostock, Germany - Environmental conditions - Plant communities on inselbergs - Adaptive strategies

2 Habitat islands as model systems for biodiversity research ceanic islands The evolution of species (Darwin 1859) Theory of island biogeography (MacArthur & Wilson 1967) errestrial habitat islands Forest fragments (e.g. BDFFP near Manaus) Rock outcrops

3 Inselbergs are old habitat islands - Geomorphology well known - Biology largely neglected Geomorphol. bekannt Biologie unbekannt

4 Koppje Inselberg types Shield inselberg Bornhardt

5 Study sites: pantropical

6 Inselbergs: terrestrial habitat islands -Sizespectrum from square meters to square kilometers

7 Granitic and Gneissic Inselbergs - Environmental conditions extreme Air Temperature ( C) rel. Humidity (%) Microclimatically extreme: elevated temperatures and high insolation rates Edaphically dry: : lack of soil cover m 0

8 Granitic and gneissic inselbergs - Habitat types

9 Lichens and cyanobacteria on inselbergs Cyanobacteria-inselberg inselberg Lichen-inselberg inselberg Peltula

10 Lichens and cyanobacteria on inselbergs Cyanobacteria-inselberg inselberg Drainage channels Lichen-inselberg inselberg Peltula

11 Wet flush vegetation on exposed rock in seasonal streams colonizing cyanobacterial mats

12 Wet flush vegetation dominant families Lentibulariaceae, Xyridaceae, Eriocaulaceae Utricularia rigida Utricularia subulata

13 Seasonally water-filled rock pools

14 Dopatrium longidens Seasonally water-filled rock pools

15 Rock pools grinding holes

16 - Spatial species turnover in rock pools

17 Inselbergs: habitat types Monocotyledonous mats West Africa frotrilepis pilosa

18 Inselbergs: habitat types Monocotyledonous mats East Africa/Madagascar Coleochloa setifera erophyta spp. yrothamnus flabellifolius/ oschatus

19 itcairnia geyskesii Inselbergs: habitat types Encholirium spec. Monocotyledonous mats Neotropics

20 Desiccation-tolerant tolerant vascular plants - Adaptations to unpredictable water scarcity dry wet dry Microdracoides squamosus Drying without dying: Desiccation-tolerant vascular plants: resurrection plants dry wet dry Myrothamnus moschatus

21 Ephemeral flush vegetation Granitic and Gneissic Inselbergs - Habitat types

22 Ephemeral flush vegetation Downslope fringes of monocot-mats Floristically exceptionally rich with spp./m 2

23 Ecological attributes of EFV Highly seasonal plant community Small habitat size Annuals dominating Small size of plants High species richness Shallow substrate Lack of nutrients High percentage of carnivorous plants dry season aspect

24 Floristic composition of EFV Australia Typical throughout most regions: Cyperaceae Poaceae Lentibulariaceae Eriocaulaceae Xyridaceae Gentianaceae Droseraceae India

25 Phylogeny and ecology of Lentibulariaceae Lamiales/Lentibulariaceae: Pinguicula, Genlisea, Utricularia

26 Tropical rock outcrops - Inselbergs - Sandstone table mountains - Ferricretes

27 Eisenlateritkrusten (ferricretes, cuirasses ferralitiques) Western Ghats

28 Eisenlateritkrusten (ferricretes, cuirasses ferralitiques) Utricularia purpurascens Mass flowering of terrestrial Utricularia-species

29 Eisenlateritkrusten (ferricretes, cuirasses ferralitiques)

30 Inselbergs and Man Tourism......and Leisure

31 Invasive species on inselbergs - Habitat fragmentation increases the percentage of exotic weeds on inselbergs - Inselbergs are evolutionary springboards of invasive species

32 Granitic and Gneissic Inselbergs - Inselbergs as refugia for maintaing biodiversity Rio de Janeiro

33 A threatened paradise of rare plants: vegetation of tropical inselbergs Conclusions: - Rock outcrops form centers of diversity for plants typical for nutrient poor and seasonally wet sites - Habitat specialists dominate (e.g. carnivorous species, resurrection plants) Major risks: quarrying, fire grazing, outdoor activities (e.g. rock climbing)

34 Acknowledgements - Funding: DAAD, DFG, ECOFAC, Smithonian Institution, Studienstiftung des deutschen Volkes - Cooperation: L. Aké Assi (Abidjan), W. Barthlott (Bonn), F. Franca (Feira( de Santana), P. Goetghe- beur (Gent), S. D. Hopper (Perth), J. Lejoly (Bruxelles), G. Martinelli (Rio de Janeiro), M. F. de Sales (Recife), F. R. Scarano (Rio de Janeiro), B. Sinsin (Cotonou), M. Ndangha (Limbe), Z. Tuba (Gödöll( llö), A. Watve (Pune( Pune)