Seasonal and spatial patterns of seed dissemination of the canopy tree Cornus controversa were studied over two fruiting seasons in a temperate deciduous forest in Japan. Seedfall was monitored every 2 wk in seed traps (N = 221) distributed over a 1-ha study plot that included 12 mature Cornus. Estimated annual seed production was 1.57 x 10 6 seeds/ha. In both years, the peak of fruit ripening had already ended before migratory frugivorous birds entered the area and only 17% of the seeds were disseminated by birds. Directly fallen seeds were deposited close to the parent trees (usually within 10m, infrequently as far as 35 m from parent trees). In contrast, bird-disseminated seeds showed a markedly scattered distribution; the birds deposited more than half of the seeds they ate > 5 m from the crown edge, and density ofbird-disseminated seeds exceeded that of directly fallen seeds at distances > 15 m, with some found > 40 m from the nearest mature Cornus.In addition, birds seemed to selectively eat fruits that contained viable seeds. The density of bird-disseminated seed decreased significantly with increasing distance from fruiting trees, both conspecific and heterospecific. Distance to the nearest edge of canopy gaps that were several years old had little effect on the spatial pattern ofbird-disseminated seeds. This means that seeds of C. controversa were not directionally dispersed into canopy gaps by birds.

Questions: 1. Is there a trade-off between gap dependency and shade tolerance in each of the life-history stages of three closely related, coexisting species, Acer amoenum (Aa), A. mono (Am) and A. rufinerve (Ar)? 2. If not, what differences in life-history traits contribute to the coexistence of these non-pioneer species? Location: Ogawa Forest Reserve, a remnant (98 ha), speciesrich, temperate deciduous forest in central Japan (36°56' N, 140°35' E, 600 -660 m a.s.l.). Methods: We estimated the demographic parameters (survival, growth rate and fecundity) by stage of each species growing in gaps and under closed canopy through observations of a 6-ha permanent plot over 12 years. Population dynamics were analysed with stage-based matrix models including gap dynamics. Results: All of the species showed high seedling and sapling survival rates under closed canopies. However, demographic parameters for each growth stage in gaps and under closed canopies revealed inter-specific differences and ontogenetic shifts. The trade-off between survival in the shade and growth in gaps was detected only at the small sapling stage (height < 30 cm), and Ar had the highest growth rate both in the shade and in the gaps at most life stages. Conclusions: Inter-specific differences and ontogenetic shifts in light requirements with life-form differences may contribute to the coexistence of the Acer species in old-growth forests, with Aa considered a long-lived sub-canopy tree, Am a long-lived canopy tree, and Ar a short-lived, 'gap-phase' sub-canopy tree.Nomenclature: Satake et al. (1989).Abbreviations: Aa = Acer amoenum; Adt1/Adt2 = Adult stages 1 & 2; Am = A. mono; Ar = A. rufinerve; Fadt1/2 = Female stages 1, 2; Juv1/2 = Juvenile stages 1, 2; Madt1/2 = Male stages 1, 2; Sapl = Large sapling; Saps = Small sapling; Sdl = Seedling.

No abstract

This study quantitatively clarifies the life history of a shrub, Sambucus racemosa ssp. sieboldiana, in an old-growth forest, the Ogawa Forest Reserve, Japan, by a demographic approach using a projection matrix model that incorporates interactions between demographic parameters and canopy height dynamics. S. racemosa is a common deciduous shrub in central Japan and is known to grow predominantly at forest edges or roadsides. This indicates that it is a highly light-demanding species, and occurrence in gaps in old-growth stands suggests its "fugitive," gap-dependent life history in old-growth forests. We found that one distinctive feature of this species was that its seedlings can survive well in shaded conditions by alternating stems every year like perennial herb species. Matrix model analyses demonstrated that S. racemosa can continuously regenerate under the present disturbance regime of this forest and is highly adaptable to the structural dynamics of the old-growth forest. The maturity of S. racemosa shrubs depends on their size, and nearly all (>90%) of the mature (reproducing) individuals were found in gaps or near gaps. But wide seed dispersal by birds and the ability to form both seed banks and seedling banks, the latter of which has been regarded as a common characteristic of shade-tolerant climax species, probably increase the species' chances to encounter canopy gaps. Dynamic-canopied matrix models showed that the greatest elasticity is with shaded seedling survival. The frequent stem alternation of shaded seedlings often makes the growth rate negative, but the survival rate of seedlings in low light awaiting new gap creation is remarkably high (0.93 yr(-1)). The lower survival rate of the larger individuals and smaller minimum size to start reproduction than other canopy or subcanopy shade-tolerant species indicate that S. racemosa has the potential to reproduce before the closure of the encountered gaps and to complete its life history rapidly.

We examined fine litterfall fluctuations on a seasonal and annual scale for 14 years (1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005) in a 1.2-ha plot in an old-growth lucidophyllous (evergreen broad-leaved) forest within the Aya Research Site, southwestern Japan. The average total litterfall input was 6.32 Mg ha -1 , of which leaf litter accounted for 60% of the total. Two high-impact typhoons struck the study area in 1993 (T9313) and 2004 (T0416) during the observation period; however, the subsequent pattern of litterfall after disturbance was different between the two typhoons. T9313 disturbance caused a reduction of biomass (ca. 10% of basal area (BA)) and a sharp decrease in litterfall input following a massive input in 1993. On the other hand, T0416 caused a minor decline in litterfall input, accompanied by a relatively small reduction of BA (5.2% of the 2001 BA). In spite of large fluctuations, litterfall input increased year by year after the T9313 disturbance. In 2000, 7 years after T9313, leaf input showed no significant differences and recorded more than 90% of pre-T9313 levels. Re-leafing from typhoon survivors may play an important role in the recovery of litterfall input in this forest. This study demonstrated how one highimpact typhoon can alter the temporal fluctuations in fine litterfall in lucidophyllous forest ecosystems.