Spotlight Series: Sisira Ediriweera & the Topographically Heterogeneous Sinharaja, Sri Lanka FDP
Sisira Ediriweera is a Professor in Ecology in the Department of Science and Technology at Uva Wellassa University in Badulla, Sri Lanka. He’s also the Principal Investigator of the 25-ha Sinharaja plot, a research site within a larger tract of forest that he first visited as an undergraduate student and then returned to for field work during his Masters of Philosophy. He has since earned a diploma in Plant Conservation Strategy from Kew Gardens, and in his spare time he enjoys cultivating orchids.
When did you realize you wanted to be a scientist/work in forest ecology? How did you decide to go down this career path?
There were two significant experiences where forest ecology began to take shape as a possible career path for me. In the first year of my undergraduate study we had a field visit to Sinharaja Forest (not the Sinharaja FDP, specifically, but the larger forest). It was a two-day field class, and during that time I met two postgraduate students who were doing fieldwork there. After discussing their experience researching in the plot, I started to think that a career where I could work outside would be an ideal one for me. Earlier I had wanted to find an administrative position in the Forest Department, however, later (after my field visits), I understood that doing forest research is ideal for me because I have a lot of opportunities to both learn and disseminate my findings.
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The second experience that affirmed my interest in forest ecology took place after I completed my undergraduate degree at University of Sri Jayewardenepura. I got an opportunity to return there as a teaching assistant in the Department of Forestry and Environmental Science, and in this role I was invited to assist a graduate student who was doing fieldwork in Sinharaja Forest. It was a seedling study, and I helped the student take measurements and record them. I enjoyed the opportunity to work with plants in the field, and it really motivated me to continue working in forest ecology. I both lived and worked at the field site during that time, and soon after returning to the University, I met the student’s advisor and pursued the possibility of joining their research programme. In the beginning, I volunteered to participate in their fieldwork, and later I was able to do my Master of Philosophy (MPhil) degree under supervision of Professor BMP Singhakumara (University of Sri Jayewardenepura) and Professor Mark Ashton (Yale University), who were the PIs of that research group.
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What led you down the path to your current job? What has been your biggest challenge in getting to this point in your career?
After completing my MPhil degree, finding a job in academia or in the research field was really challenging. Eventually I found work as a Field Assistant for a Habitat Mapping Project of the Department of Wildlife Conservation. It was a great opportunity to work in different national parks across the country, and I gained good experience in conducting field surveys on vegetation structure and composition. It was an opportunity that also helped me to practice plant identification and working on a team. Towards the latter part of this project, in 2005, I was able to earn a diploma in Plant Conservation Strategy at Kew Botanic Gardens. Soon after I returned home, I was lucky to receive a position as a Lecturer in Biology at the newly established Uva Wellassa University, where I am affiliated currently.
When did you first get involved in the ForestGEO network?
The second census of the Sinharaja FDP took place in 2001, and at that time I was in the Sinharaja plot doing field work for my MPhil. When I wasn’t doing field work for my research, I had a brilliant opportunity to work at the plot as a field assistant for the census. For approximately 10 months I worked there, and during this period I met Dr. I-Fang Sun (then coordinator of the CTFS [ForestGEO] Asian plots), who gave me lots of good advice on field methods for the census and some valuable comments for my MPhil research as well. Dr. Sun invited me and helped me to obtain funding to attend the first International Field Biology Course, which was organized in 2001 by CTFS (ForestGEO) at the Pasoh plot in Malaysia. It was my first overseas visit, and I met several scientists from other countries, including Dr. Stuart Davies and Prof. Takakazu Yumoto.
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What is the most interesting or unique aspect of your site?
The 25-ha Forest Dynamics Plot at Sinharaja is among the most topographically heterogeneous of ForestGEO plots. Additionally, while supporting a very large number of stems per unit area relative to the other large plots, the Sinharaja FDP also has several series of closely related congeneric, sympatric species. The majority of these are endemic to Sri Lanka.
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What questions are you currently addressing in your research/site?
I’m quite new as a PI of the plot. Until 2018 the plot was managed by University of Peradeniya (now it is coordinated by Uva Wellassa University), and Profs. Nimal and Savitri Gunatilleke (founders) were the PIs of the plot. My first order of business was to lead the plot’s fifth census, which began in January 2018. All fieldwork was completed by April 2019, and data entering and accuracy checking are currently in progress. I recently re-measured three sites (5-ha with minimum dbh of 10 cm) which were established in 1978 by Prof. Savitri Gunatilleke, and we published our findings on how structural characteristics, species composition, species richness and demographic rates change over time and among sites. Another recent project was an investigation of canopy dieback in Horton Plane National Park, a montane forest in Sri Lanka.
What kind of capacity building opportunities does your site provide for students, early-career researchers, and the local community?
Sinharaja FDP welcomes all. The project employs and trains members from the local community as field assistants. Undergraduate students, postgraduate students, and early-career researchers are welcome to use the plot for their research if their objectives are in line with the objectives of having a large forest permanent plot. Over the last 25 years local undergraduate and post graduate students, as well as several post graduate students from overseas (especially from Yale University-USA), conducted field work at Sinharaja FDP. Currently one PhD research project and four MPhils research projects are in progress in the plot.
What do you like to do when you’re not studying forest dynamics?
I spend my weekend and free time on gardening. I have an orchid collection.
Recent Publications
Ediriweera, S.; Bandara, C., Woodbury, D. J., Mi, X., Gunatilleke, I. A.U.N., Gunatilleke. C.V. S., Ashton, P.S., (2020) Changes in tree structure, composition, and diversity of a mixed-dipterocarp rainforest over a 40-year period. Forest Ecology and Management 458, 117764. doi: 10.1016/j.foreco.2019.117764
Bandara, C., Priyankara, T., Atthanagoda, A. G., Lakkana, T., Ediriweera, S. & Kumar, P (2020) Gastrodia gunatillekeorum (Gastrodieae, Epidendroideae, Orchidaceae), a new species from a lowland rainforest of Sri Lanka, Phytotaxa, 436 (8): 55–62. doi: 10.11646/phytotaxa.436.1.5
Ashton, M, Hooper, E., Singhakumara, B, Ediriweera, S. (2018) Regeneration recruitment and survival in a tropical rain forest: Implications for sustainable management. Ecosphere 9(2): 1-16. doi: 10.1002/ecs2.2098