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To evaluate the effectiveness of sustainable forest management (SFM) for wildlife conservation, we investigated the abundances of medium to large ground-dwelling vertebrates in a forest management unit in Borneo by camera trapping. The forest management unit (FMU), Deramakot Forest Reserve (55,083 ha), has applied SFM for the past 15 years. We established 15 plots in preharvested areas and five plots in postharvested areas over the FMU. Plots in the postharvested areas had been subject to reduced-impact logging from 2 to 13 years ago. We obtained photos of ground-dwelling vertebrates with infrared sensor cameras set at 12 random points in each plot. Based on the numbers of photos taken over 770 camera days in each plot, we calculated the mean trapping rate (MTR) of each species for each plot. Over the 20 plots, we obtained 5444 photos of 39 medium-to-large vertebrates (i.e., mammals, birds, and monitor lizards); these included many elusive and endangered species. Among the 39 species, no species showed a significant difference in MTR between the pre- and postharvested areas. Furthermore, species composition was not significantly different between the pre- and postharvested areas. Our results support the idea that implementation of SFM can be an effective investment in wildlife conservation in tropical rainforests.

In this paper previously unpublished field data from 25 ha of permanent sampling plots (PSPs) in Sabah, Malaysia, in four different forest reserves are analysed for mortality rates and basal area development. Field data of an observation length of 9 to 20 years were available. These data then form the basis of several benchmark tests for the evaluation of the individual-oriented tropical rain forest growth model formind . A new version of the formind is presented. The model in its version formind1.1 includes enhanced submodels for mortality and tree growth. The model evaluation is focused on the model components for tree growth, competition and mortality. Data for tree recruitment were not available. Results show a good agreement between simulation and field data for the main output variables basal area and stem number indicating a reasonable behaviour of the model components we focused on. Furthermore the results show that differences in site conditions influence tree growth and mortality. Site characteristics should be included in the model in the future.

We studied the effects of forest composition and structure, and related biotic and abiotic factors on soil respiration rates in a tropical logged forest in Malaysian Borneo. Forest stands were classified into gap, pioneer, non-pioneer and mixed (pioneer, non-pioneer and unclassified trees) based on the species composition of trees >10 cm diameter breast height. Soil respiration rates did not differ significantly between non-gap sites (1290 ± 210 mg CO2 m-2 h-1) but were double those in gap sites (640 ± 130 mg CO2 m-2 h-1). Post hoc analyses found that an increase in soil temperature and a decrease in litterfall and fine root biomass explained 72% of the difference between gap and non-gap sites. The significant decrease of soil respiration rates in gaps, irrespective of day or night time, suggests that autotrophic respiration may be an important contributor to total soil respiration in logged forests. We conclude that biosphere-atmosphere carbon exchange models in tropical systems should incorporate gap frequency and that future research in tropical forest should emphasize the contribution of autotrophic respiration to total soil respiration. © 2009 Elsevier B.V. All rights reserved.