All termite feeding groups were positively associated

All termite feeding groups were positively associated LEE011 in vivo with axis 1 (i.e. with low disturbance levels), with dead wood/leaf litter feeders (Group II) and organic soil feeders (Group III) being strongly so, dead wood/feeders (Group I) and fungus-growing termites (Group IIF) being more weakly associated, and true soil feeders (Group IV) having the weakest association of all (note, there

were very few Group IV occurrences) (Fig. 2b). Axis 2 accounted for only 2.5 % of assemblage variation. Group IIF and Group I showed stronger associations with axis 2 than axis 1, being positively and negatively associated with bare ground cover, respectively (Fig. 2b). Discussion Both ants and termites inhabiting soil and dead wood varied in occurrence and functional group composition with habitat disturbance. However, the results selleck chemical differed greatly between the two taxa. All termite feeding groups showed fewer occurrences in more disturbed sites, whereas ant functional groups showed more idiosyncratic patterns. Variation in functional group occurrence was related to habitat treatment for both ants and termites, but the strength of associations with other variables differed between the taxa. Ants were well

represented in disturbed habitats, with occurrences highest in logged forest. Studies in Amazonia have also found high ant abundances in moderately disturbed habitats such as re-growth forest and fragment edges (Didham 1997; Vasconcelos Oxymatrine 1999). Andersen (2000) considers low temperature, lack of nest sites (e.g. rotting logs), poor food supply, and high structural complexity of foraging surfaces to be the main stressors limiting ant populations. Logged forests may offer intermediate conditions that favour greater ant abundance, in which nest sites are available, but surfaces are not too complex to limit foraging, with temperatures slightly higher on average than in old growth forest. However, more highly disturbed forests, such as secondary regrowth following clearance, support fewer species due to differences in tree density, diversity and size distribution (Klimes et al. 2012). In contrast, termites

were more common in old growth forest than in the other two habitats. Many termites require a closed canopy to buffer microclimate and avoid desiccation, as well as relatively clayey soils rich in organic material for colony building and food (Eggleton et al. 1997, Hassall et al. 2006). Logging, habitat clearance and conversion to oil palm plantation lead to hotter and drier microclimate (Turner and Foster 2006), and the disruption of soil structure by logging tracks (Malmer and Grip 1990). These differences may have been accentuated by a drought that was just ending during the sampling period (see http://​www.​searrp.​org/​danum-valley/​the-conservation-area/​climate/​), because disturbed forests may be less able to buffer microclimate (Ewers and Banks-Leite 2013).

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