In situ and Ex situ Conservation of Commercial Tropical Trees - ITTO

367and one site of Silvagama in Kuamang Kuning, in Jambi Province. Forestfragmentation in Jambi Province and on the entire island of Sumatra is mainlydue to land clearing for settlement and transmigration, as well as to landconversion for agriculture, and it has to be controlled. Further research involvingmore species, various histories, and various physical conditions is needed tocontribute in formulating conservation action plans in Sumatra and in Indonesia.One factor to consider in decision making for genetic conservation ishow effective the plan for management might be. The management optionsmay involve only locking up the resource in some kind of reserve, or leaving italone. The decision is to create a reserve or not, and the problem for theconservationist is to estimate the relative probability of sufficient survival of theresource with and without the reserve. For other conservation programs, moreoptions may be available, but each has its own cost and probability for achievingthe desired results and values. The benefit of each option may then be estimatedfor both present and future values to society.AcknowledgementsThese studies were partly supported by ODA Grant (R6403H), Center forInternational Forestry Research (CIFOR), and IPGRI (International PlantGenetic Resources Institute). The authors are grateful to Dr. T.J.B. Boyle forfacilitating some of the studies and to Faculty of Forestry, Gajah Mada Universityand PT. IFA-Barito Pacific Timber Group-SEAMEO BIOTROP for providingassistance and facilities during the fragmentation study.ReferencesAckerly, D.D., Rankin-de-Merona, J.M. & Rodriques,W.A. 1990. Tree densities and sex ratiosin breeding populations of dioecious Central Amazonian Myristiceae. J. Trop. Ecol. 6: 239-248.Ayres, D.R. & Ryan, F.J. 1997. The clonal and population structure of a rare endemic plant,Wyethia reticulata (Asteraceae) : allozyme and RAPD analysis. Molecular Ecology 6: 761-771.Baruffi, L., Damiani, G. & Guglielmino,C.R. 1995. Polymorphism within and betweenpopulations of Ceratitis capitata: comparison between RAPD and multilocus enzymeelectrophoresis data. Heredity 74: 425-437.Beismann, H., Barker, J.H.A.. Karp, A., & Speck, T. 1997. AFLP analysis sheds light ondistribution of two Salix species and their hybrid along a natural gradient. Mol. Ecol. 6: 989-993.Gaiotto, F.A., Bramucci, M. & Grattapaglia, D. 1997. Estimation of outcrossing rate in a breedingpopulation of Eucalyptus urophylla with dominant RAPD and AFLP markers. Theor. &Appl. Genet. 95: 842-849.Gratapaglia, D., & Sederoff, R. 1994. Genetic linkage maps of Eucalyptus grandis and Eucalyptusurophylla using a pseudo-testcross: mapping strategy and RAPD markers. Genetics 137: