Remarks on the species composition of ephemeral flush communities on paleotropical rock outcrops
Porembski, Stefan; Watve, Aparna
Granitic and gneissic inselbergs and ferricretes are characterized by extreme environmental conditions (e.g. lack of soil, high temperatures, limited water availability) and are widespread in many tropical regions. Due to their character as edaphic islands there are significant differences in comparison to the surrounding vegetation. These rock outcrops form azonal habitat complexes that harbour a number of different plant communities. Among the latter ephemeral flush vegetation (EFV) is a prominent example of a highly seasonal community that is characterized by the prevalence of specialized annual species. Throughout the tropics EFV is constituted by taxa that are indicative for nutrientpoor and seasonally wet localities. Amongst the latter Eriocaulaceae, Xyridaceae and carnivorous Lentibulariaceae and Droseraceae are of frequent occurrence with Poaceae, Cyperaceae and Commelinaceae being likewise well represented. Phytosociologically EFV belongs to the class Drosero-Xyridetea that is widespread on tropical rock outcrops.