Forest tree growth and dynamics at La Selva, Costa Rica (1969-1982)

Abstract

ABSTRACTPermanent plots totalling 12.4 hectares were established in 1969 in primary tropical wet forest at La Selva Biological Station, Costa Rica; all stems ≥10 cm diameter at breast height were tagged and measured. In 1982, the plots were again censused, and all live trees re-measured. Mortality over 13 years was 23.2%, or 2.03% per year based on a logarithmic mortality model. This suggests a stand half-life of around 34 years. Mortality was independent of size class in trees ≥10 cm diameter. Recruitment was equal to mortality. Tree growth curves and age-size relationships for 44 species were projected from 13-year diameter increments using a growth simulation procedure. Understorey trees grow slowly and consistently, and have short life spans; subcanopy trees also grow slowly, but live longer; shade-tolerant canopy trees show variable and often rapid growth and are long-lived; and shade-intolerant canopy trees grow rapidly, show little variation, and have short life spans. The longest imputed life span in our sample was around 440 years (years from 10 cm diameter to the maximum diameter); the shortest life span was around 50 years.