IMPACT OF HURRICANE INIKI ON NATIVE HAWAIIAN ACACIA-KOA FORESTS - DAMAGE AND 2-YEAR RECOVERY

Damage to Hawaiian Acacia koa forest by Hurricane Iniki was assessed b y comparison with our previous measures of stand structure and leaf ar ea index (LAI) at sites along a precipitation/elevation gradient on we stern Kauai. Reductions in LAI ranged from 29 to 80% and were correlat ed with pre-hurricane LAI and canopy height. The canopy damage resulte d in a large pulse of litter, ranging from 4 to 19 t ha(-1) across our study sites. In the first year post-hurricane, LAI recovery and relat ive increase in stand basal area were negatively correlated with the f raction of canopy LAI lost. The two major overstorey species, A. koa a nd Metrosiderous polymorpha, were damaged less than the sub-canopy spe cies, Dodonaea viscosa and Psidium guajava. Although D. viscosa and P. guajava were both severely damaged in the hurricane, the alien specie s P. guajava had much higher survival than the native D. viscosa, both as adults and as seedlings. However, seedling density of P. guajava w as limited by low recruitment. At these sites, there was no drastic ch ange in species composition following hurricane disturbance, and fores t structure and productivity had recovered to a great degree within 2 y.