The Quantity, Temporal Distribution and Mineral-Element Content of Litterfall in Two Forest Types at Two Sites in Tropical Australia

Publisher Website
Google Scholar
Abstract
Litterfall in a plantation of Araucaria cunninghamii and in an adjacent rain forest was compared at 2 sites in northeastern Australia over 3 and 4 yr, respectively, for quantity, temporal distribution, and the content of N, P, Na, K, Ca and Mg. The average litterfall for the 4 plots was 9.25 t/h per yr, a result comparable with values from similar studies on other tropical forests. There were no consistently significant differences in the quantity of litterfall between forest types or sites, or between years for the rain forest plots. Litter from the rain forest plots at both sites had significantly higher concentrations of N and K than litter from the Araucaria plots. Litter from both forest plots at the site where the soil was more fertile was significantly higher in concentrations of N, P, K and Ca than litter from the less fertile site. For N, the differences between plots in the 2 forest types were greater than the differences between sites. The Ca content of Araucaria litter during the period of heavy seed production in Dec.-Jan. of the 2nd study yr was lower than at all other times. Na was the only one of the mineral elements studied to show a regular seasonal pattern of concentration, with lower concentrations in the wet season than during the dry season. In spite of the significant differences in the mineral-element concentrations of litter both between forest types and between sites, there were no significant differences in annual mineral-element accessions to the soil. There appears to have been little effect on the annual accession to the soil of litter and the associated mineral elements as a result of the conversion of rain forest to Araucaria plantation at each site; differences between sites in properties such as soil fertility and rainfall also had little effect.