Responses of ground-active beetle assemblages to different styles of reforestation on cleared rainforest land

Abstract

Despite increasing eVorts to re-establish forest cover in landscapes that have been previously cleared, the relative ability of diVerent styles of reforestation to contribute to conservation and support forest biota is poorly known, particularly for invertebrates. We investigated the use of diVerent types of reforested habitat by ground-active rainforest beetle assemblages on land, which had been previously cleared of rainforest, in the tropics and subtropics of eastern Australia. Between Wve and ten replicate sites within each of Wve reforestation styles were selected in each region: un-managed regrowth, young mono-species timber plantations, young mixed-species timber plantations, ecological restoration plantings, and old monospecies timber plantations, together with reference sites in pasture and in intact rainforest. Ground-active beetles were sampled using pitfall traps, and assemblages were compared among site-types. In both regions, beetle assemblages in all styles of reforestation were intermediate in species composition between pasture and rainforest. The similarity of beetle assemblages to intact rainforest increased with the age and structural complexity of reforested sites. The most rainforest-like beetle assemblages were from older reforestation sites (38-70 year plantations in tropics, and 30-40 year regrowth in subtropics) and in younger (6-22 years) but Xoristically and structurally diverse ecological restoration plantings in both regions.Assemblages in younger (5-20 year) sites of regrowth, mono-species timber plantations, and mixed-species timber plantations were more similar to pasture than rainforest. We conclude that achieving high canopy cover and suYcient structural complexity are important factors associated with the restoration of rainforest-like beetle assemblages to reforested sites.

Arthropod recolonization in the restoration of a semideciduous forest in southeastern Brazil

“…Species accumulation curves of arthropods in the tropics and subtropics generally do not reach an asymptote due to the large set of rare species which accumulate with increasing sample size (Price et al 1995, Novotný & Basset 2000, Santos et al 2006, Grimbacher et al 2007. For such groups, more intensive sampling typically never generates curves that completely fl atten out and reach a plateau (Fisher 1999).…”

“…We did not actually intend to compile a species inventory but to achieve adequate spatial replication (Grimbacher et al 2007). Also, sampling was not seasonal, i.e.…”

“…Even though species richness is considered to be the most easily restored component of biodiversity, recovery of species richness usually takes longer periods, e.g., around 20-40 years for several animal taxa (Dunn 2004) or up to 5-15 years for ground-active beetles in rainforest restoration (Grimbacher et al 2007).…”

“…△= forest remnant, ▲ = REV1, ▽ = REV2, ▼ = REV3; ◇ = REV4 (all morphospecies included in the analysis). Burger et al 2003, Grimbacher et al 2007. One of the few exceptions seems to be a rehabilitation site in Australia, which grouped with reference sites in multivariate analysis of ant assemblage (Andersen et al 2003).…”

Effects of aspect and type of competition on the early performance of Nothofagus dombeyi and Nothofagus nervosa in a mixed plantation

“…This design can be effective in preventing early interspecific competition and in ensuring maintenance of the initial diversity in terms of species and area occupied by them (Scherer-Lorenzen et al 2005). If successful, this type of plantation should have a greater diversity (Montagnini 2001;Díaz et al 2005;Grimbacher et al 2007;Piotto 2008) and increased productivity or value compared with a pure plantation, the latter especially due to a greater quality of individual trees (Kelty et al 1992;Donoso et al 1999). In this context, we sought to compare the performance of two Nothofagus species in a young mixed plantation with a checkerboard design on a favorable site for both species.…”