7 Jul (Wed): Talk on "Tree vs. Tide - How mangroves colonise bare mudflats"

Colonization of a bare tidal flat by Avicennia spp. is an important and critical phase in the development of a mangrove forest. Early establishment success is determined by a strategy to quickly anchor the buoyant propagule in the soil to resist hydrodynamic forcing.

By flume and growth experiments we show that early establishment success of Avicennia propagules is depending on pre-establishment time with freedom from inundation and hydrodynamic forcing by waves during the first days. Once seedlings are anchored to withstand daily hydrodynamic forcing, dislodgement can only be caused by sheet erosion.

Present findings elucidate tipping points in mangrove colonization. The results of combined growth and flume experiments offer insight in natural mangrove colonization or regeneration and success of mangrove restoration projects.

About the speaker: Thorsten Balke is specialising in landscape evolution of the intertidal coastal zone due to interactions between hydrological and geomorphological processes with living organisms like salt marsh vegetation or mangrove trees. This is often called biogeomorphology or ecosystem engineering. For his PhD research (2009-2013) he is looking at biogeomorphic succesion of mangroves. He want to elucidate the biophysical processes and tipping points during colonisation of a bare tidal flat and furthermore the impact of established vegetation on sedimentation and stabilisation. To achieve this I will carry out flume studies, growth experiments in hydrodynamic mesocosms and a wide range of field methods. He studied physical geography in Hanover (Germany) and Salford (UK) in 2004-2009. He wrote his final thesis at the Netherlands Institute of Ecology (NIOO-CEME) in Yerseke with the title: Biogeomorphology of Spartina anglica tussocks - A GIS comparison of contrasting sites at the Westerschelde and Blackwater estuary.

More about the Singapore Delft Water Alliance.

Time: 3-4pm
Venue: E1-08-25 SDWA Conference Room National University of Singapore
Website and contact: http://www.sdwa.nus.edu.sg/