Abstract booklet - gtö – Society for Tropical Ecology

218 SCIENTIFIC POSTER SESSION | FOYERSCIENTIFIC POSTER SESSION | FOYER219Topic: Tropical aquatic ecosystems: diversity, ecophysiological processesconservationFree contributionFLORISTIC ASSESSMENT OF 10 HECTARES OF BLACK-WATERINUNDATION FOREST (IGAPÓ) ACROSS THE NEGRO RIVER,CENTRAL AMAZONIA.RESPONSE OF COCOA TREES (THEOBROMA CACAO) TO A13-MONTH DESICCATION PERIOD IN SULAWESI, INDONESIAJuan Carlos Montero 1 , Florian Wittmann 2 , Maria Teresa FernandezPiedade 3 , Albert Reif 4Gerald Moser 1 , Dietrich Hertel 2 , Christoph Leuschner 2 , Erma Prihastani 3 ,Daniela Leitner 2 , Beate Michalzik 41University of Freiburg, Plön, DE, carlos.montero@waldbau.uni-freiburg.de, 2 MaxPlanck Institute for Chemistry Biogeochemistry INPA/Max Planck Project, Manaus,BR, 3 Instituto Nacional de Pesquisas da Amazônia INPA/Max Planck Project,Manaus, BR, 4 Insitute of Silviculture, University of Freiburg, Germany, Freiburg, DE1Giessen University, Gießen, DE, Gerald.Moser@bio.uni-giessen.de, 2 GöttingenUniversity, , De, 3 Faculty of Mathematics and Natural Sciences, DiponegoroUniversity, Semarang, Indonesia, , Indonesia, 4 Jena University, Jena, DEWEDNESDAY | FOYERThe majority of floodplain research concentrates on white water forests, whileigapó forests were scarcely inventoried. Little information is available about theflora of the igapó and most floristic inventories concentrated on the lower NegroRiver, near the city of Manaus. Based on a botanical inventory of 10 ha (160 x625m2) in late-successional igapó forests along the upper, middle and lowersections of the Negro River, we examined phytosociological parameters andspecies composition for all plots combined and for each river section by meansof ecological indices (IVI and FIV). Similarly, we evaluated species richness anddiversity using various measures and estimators. Overall, we registered 6126individuals of 244 species distributed in 136 genera and 51 families. The 30 mostimportant species accounted for 58.43% of the importance value; in which theemergent legume Aldina heterophylla (Fabaceae) presented the highest valuewith 6.80% followed by Gustavia augusta (Lecythidaceae) and Heterostemonmimosoides (Caesalpinaceae) with 3.61% and 3.59% respectively. More than 50% of family importance value is represented by only 5 families such as Fabaceae(16.93%), Caesalpinaceae (10.02), Euphorbiaceae (9.61%), Lecythidaceae(9.10%) and Chrysobalanaceae (6.84%). The present study contributes basicfloristic data and forms the basis of several to be done aiming to provideknowledge and understand the relationship between the igapó forests andthe flooding and edaphic gradients, in particular, the floristic and structuralvariation across the course of the river. These results also contribute essentialdata for the management and conservation of black water systems.Cacao is a major cash crop and driver of deforestation in Sulawesi. In thisecosystem experiment we studied if shaded cacao trees are vulnerable to ENSOdroughts. We installed 3 sub-canopy roofs and 3 control plots (each 35mx35m) ina cacao plantation in the Kulawi Valley in direct vicinity to the Lore Lindu NationalPark, Central Sulawesi. The roofs were closed from March 2007 until April 2008.During the first months ofdesiccation roof cover wasincreased from 60 to 80% ofthe plot area.During several monthscocoa trees were exposedto soil water contentsclose to the conventionalwilting point, but showedno significant decreasesin leaf biomass, stem andbranch wood production orfine root biomass. Possiblecauses are active osmoticadjustment in roots,mitigation of drought stressby shading from Gliricidiatrees, root space partitioning or missing atmospheric drought conditions.Production of cocoa beans was significantly reduced in the roof plots. We concludethat cacao bean yield appears to be particularly drought sensitive, and that cropfailure potentially accelerates forest transformation.Wednesday WEDNESDAY 16:00 | FOYER | FoyergtöSociety for Tropical Ecology | Gesellschaft für Tropenökologie e.V. Status and future of tropical biodiversity | Frankfurt, 21 - 24 February 2011gtö