A mathematical analysis on the dependence of extinction probability on life history characteristics in plant populations

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We have monitored the fate (growth, survival and death) of individuals of four woodland herbaceous species with different life histories in their permanent plots. We also conducted a research to measure fruit and/or seed set in each species at the fruiting period and collected the information on fecundity. Furthermore, as for Trillium camschatcense, we measured the light intensity and soil moisture from the edge to inside of fragmented forests with various sizes in Tokachi area of Hokkaido, and evaluated the effect of the gradient of physical environment on Trillium camschatcense population.In theoretical analysis, we explored a method to evaluate the sensitivity and elasticity of population growth rate in density-dependent matrix model, which is the quantities to estimate the effect of the change of life history parameters on population growth rate. Two papers on the results are submitted and accepted in academic journals (see `References` on back page). We also conducted a statistical analysis of the census data already obtained in order to employ in simulation programs to calculate extinction probability of populations. Consequently, we obtained the correlation between fecundity and mortality rate, and the dependence rate of seed reproduction and vegetative reproduction in each species. Utilizing those obtained results, we constructed a simulation program to calculate the extinction probability of populations after 100 years. The calculated results are written in the English papers and they are submitted to academic journal and in review now.