Preliminary account of litter production in a New Zealand lowland podocarp-rata-broadleaf forest

Abstract

Litter-fall was collected in 69 traps at monthly intervals for 2 years (1971–73) and macro-litter on four 100 m² plots for 1 year on 2.25 ha of lowland evergreen forest near Wellington, North Island. Litter fell throughout the year, with marked peaks of leaf-fall in summer and of other litter (mainly fruits and twigs) in winter. Mean percentages by weight of leaf litter originating from the three forest strata and from epiphytic vegetation were: tall emergent stratum 14%, tall canopy 37%, low canopy and shrubs 33%, and epiphytes 16%. Mean total litter-fall was 6 865 kg (dry weight) /ha/annum, leaves constituting 3 229 kg/ha/annum (47%), and the estimated calorific content of total litter was 32 × 10⁶ kcal/ha/annum. This is greater than the litter-fall recorded for New Zealand Nothofagus forest but is only about half that reported for tropical rain forest with which New Zealand podocarp-rata-broadleaf forest has many structural and floristic similarities.