Hometown:Sri Lanka, Colombo
Advisor: Graeme Berlyn
All life on earth is maintained by the flow of energy radiated by the sun that enters the biosphere. This energy, in the form of light, is the most important physical factor that controls the development of tree seedlings in tropical rainforests. The overall objective of my study is to investigate the ecophysiology of pioneer tree seedlings in relation to light and their ability to acclimate to change in light. Ecophysiology refers to the study of an organism's interaction with its environment nd the causal analysis of the corresponding ecologically dependant physiological mechanisms involved. Phenotypic plasticity refers to the ability of an organism to express different morphological, anatomical, and physiological traits in response to environmental conditions. Being modular organims, plants change their phenotypic expression in relation to change in environmental conditions. this is known as acclimation. Thus the study of ecophysiology and phenotypic plasticity of these pioneer species in response to light as well as the acclimation to change in light are directly linked to understanding their habitat preference and adaptability to the vast changes that occur during canopy opening and closing. I hypothesize that the variation in plasticity and acclimation in response to light between the pioneer species determines which gap conditions they are able to colonize most successfully. The species studied will include Macaranga peltata, Macaranga indica, Dillenia triquetra, Schumacheria castaneifolia, Wendlandia bicuspidata, and orientalis. I will conduct controlled shade house experiments at the research station of the Sinharaja World Heritage Site in Sri Lanka and complement the shade house investigation with field studies at the Sinharaja fores. Plasticity in response to light and acclimation in response to change in light environment will be assessed by integrating various levels of plant organization; from leaf based morphological, anatomical, physiological, and biochemical characteristics to whole plant level characteristics such as biomass allocation and growth rate. This research will improve our understanding of how plasticity varies among species of the pioneer guild. It can also shed light on interspecific mechanisms involved in forest stand development at the early successional stage. Further, pioneer trees species play an important role in forest regeneration following disturbance, and may be useful in restoring degraded land. Pioneer species could be used in reforestaion and restoration is to facilitate the growth of late-successional native species. The different leaf and crown characteristics of the pioneer species could be manipulated using specific planting designs to create microclimatic conditions that are conducive to the growth of the late successional species. Therefore, this study could provide information to assess the feasibility of using pioneers for reforestaion and the sustainable management of marginal land in the tropical forests.
Uromi and her husband Eben both do their
research
at the Sinharaja Rain Forest.
Uromi is building her greenhouses and
Eben is off to record birds
Uromi and Eben with their field assistants and
their families celebrating their anniversary
in 2002