| 要旨トップ | 本企画の概要 | | 日本生態学会第56回全国大会 (2009年3月,盛岡) 講演要旨 |
企画集会 T01-3
Using the data from 11 dipterocarp species in the Pasoh 50-ha plot, we examined relationships between mortality rate, growth rate, habitat association, and spatial patterns of three growth stages for these tree species. Mortality rates for these species were positively correlated with RGRs although the correlation was significant only at the smallest size stage. Seven species with the high growth and mortality rates exhibited peaks in spatial aggregation at small distances (< 100 m) during the smallest stage, but this aggregation disappeared at the larger two growth stages. In contrast, the other four species with low growth and mortality rates aggregated at large distances (> 200 m) throughout three growth stages in all but one species. Negative associations between different growth stages were observed only for high-mortality species, suggesting density-dependent mortality. High-mortality species showed habitat associations with topography and soil type, whereas most of low-mortality species exhibited no habitat association. A randomization procedure revealed that these habitat associations explained little of their spatial aggregation patterns. Our results suggest that the growth strategy has a large effect on structuring the spatial distribution of tree species through mortality processes.