Above-ground phytomass of a site disturbed by selective logging in north Queensland wet tropical rainforest

Species composition and phytomass were determined for the vegetation recolonising a disturbed site in the wet tropical rainforest of the Mt. Spec State Forest, Queensland, Australia. Construction of a log loading ramp in 1963/64 resulted in the formation of a gap of approximately 900 m2, and compaction of the soil. Soil bulk density is still 45 % higher, compared to the surrounding undisturbed forest, 27 years after the construction of the ramp. Twenty-four years after disturbance, the gap was dominated by the pioneer species Alphitonia petrei Braid and C. T. White, Alphitonia whitei Braid and Polyscias australiana (F. Muell.) Philipson. Secondary species, Cardwellia sublimis (F. Muell.) and Darlingia darlingiana (F. Muell.) L. Johnson were also abundant. The mean canopy height and total basal area were 15.5 m and 17.5 m2 ha-1, respectively. An above-ground phytomass of 52 t ha-1 was found for this site; foliage comprising 6.4%, stems and branches 93.2 %, and reproductive structures 0.4%. The phytomass was substantially lower than that predicted from published phytomass data for tropical rainforests subjected to moderate disturbances.