Reproductive phenology, pollination and seed dispersal syndromes on sandstone outcrop vegetation in the "Chapada Diamantina", northeastern Brazil: population and community analyses

Abstract

-(Reproductive phenology, pollination and seed dispersal syndromes on sandstone outcrop vegetation in the "Chapada Diamantina", northeastern Brazil: population and community analyses). Vegetation on rock outcrops in the "Chapada Diamantina" (soil islands) is often aggregated and surrounded by nude rock surfaces, thus creating natural units with well defined limits. The flowering and fruiting cycles of plants on 58 soil islands at altitudes between 1,100 and 1,140 meters above sea leavel were analyzed at Mãe Inácia Peak (12°27' S and 41°28' W) in the "Chapada Diamantina", Bahia, Brazil. The presence/ absence of flowering and fruiting species on each soil island, and their respective cover areas were analyzed at both the population and community levels, and the phenophases of flowering and fruiting were observed during 24 successive months. The analyses of pollination and seed dispersal syndromes indicated that animals are more important in pollination than in seed dispersal (which is predominantly by anemochory and autochory). The flowering and fruiting of plants with animal pollination syndromes were correlated with rainfall and temperature. The flowering season varied during the year according to the pollination syndrome involved: entomophily was predominant from summer through autumn, ornithophily was predominant during winter, and anemophily in the spring. The staggered timing of flowering and fruiting among different species provides a nearly continuous supply of resources for the local fauna.

Massive post-fire flowering events in a tropical mountain region of Brazil: high episodic supply of floral resources

“…This pattern differs from the annual or continuous patterns of other species of Velloziaceae studied in the Chapada Diamantina region (Conceição et al 2007b). The two post-fire flowering events evaluated in the present study occurred during two different seasons, the first occurring during the wet season (138.8 mm total rainfall in the 42 days between the fire and the flowering event) and the second occurring during the dry season (only 22.2 mm total rainfall in the 35 days between the fire and the flowering event).…”

“…The monocot family Velloziaceae is dominant on sandstones summits in the Chapada Diamantina region (Conceição et al 2007a). The reproductive phenology of Velloziaceae responds to rainfall (Ayensu 1973;Conceição et al 2007b) and to fire (Conceição & Orr 2012), producing flowers that represent resources to many kinds of animals in rocky grassland communities in tropical montane regions (Ayensu 1973;Laudau et al 1998;Jacobi & Sarto 2007;Conceição & Orr 2012). Here, we report the massive blooming of Vellozia sincorana L.B.Sm.…”

Life-forms, pollination and seed dispersal syndromes in plant communities on ironstone outcrops, SE Brazil

“…Life-forms and syndromes of each species were assigned by examining voucher specimens, through extensive use of literature which included community-level studies (e.g. Buzato et al 2000;Griz & Machado 2001;Batalha & Martins 2002;Freitas & Sazima 2006;Kinoshita et al 2006;Martins & Batalha 2006;Conceição et al 2007), and from direct fi eld observations, particularly those of Jacobi et al (2007).…”

Fenologia de três espécies de Myrsine l. em floresta secundária semidecídua no Sul do Brasil

“…As espécies de Myrsine são pioneiras em áreas de regeneração, e seus frutos necessitam ser ingeridos por aves para viabilizar a germinação (PINESCHI, 1990;SIQUEIRA, 1993). A produção contínua de frutos dispersos por animais tem sido associada frequentemente a uma estratégia para a manutenção de recursos aos animais dispersores de sementes (SNOW, 1965;HILTY, 1980;CONCEIÇÃO et al, 2007).…”