Termite assemblages, forest disturbance and greenhouse gas fluxes in Sabah, East Malaysia

A synthesis is presented of sampling work conducted under a UK government-f unded Darwin Initiative grant undertaken predominantly within the Danum Val ley Conservation Area (DVCA), Sabah, East Malaysia. The project concerned t he assemblage structure, gas physiology and landscape gas fluxes of termite s in pristine and two ages of secondary, dipterocarp forest. The DVCA termi te fauna is typical of the Sunda region, dominated by Termes-group soil-fee ders and Nasutitermitinae. Selective logging appears to have relatively lit tle effect on termite assemblages, although soil-feeding termites may be mo derately affected by this level of disturbance. Species composition changes , but to a small extent when considered against the background level of com positional differences within the Sunda region. Physiologically the assembl age is very like others that have been studied, although there are some spe cies that do not fit on the expected body size-metabolic rate curve. As els ewhere, soil-feeders and soil-wood interface-feeders tend to produce more m ethane. As with the termite assemblage characteristics, gross gas and energ y fluxes do not differ significantly between logged and unlogged sites. Alt hough gross methane fluxes are high, all the soils at DVCA were methane sin ks, suggesting that methane oxidation by methanotrophic bacteria was a more important process than methane production by gut archaea. This implies tha t methane production by termites in South-East Asia is not contributing sig nificantly to the observed increase in levels of methane production worldwi de. Biomass density species richness, clade complement and energy flow were much lower at DVCA than at a directly comparable site in southern Cameroon . This is probably due to the different biogeographical histories of the ar eas.