The tropical peat swamp forests of Indonesia and Malaysia are unusual ecosystems that are rich in endemic species of Xora, fauna and microbes despite their extreme acidic, anaerobic, nutrient poor conditions. They are an important refuge for many endangered species including orang utans. Ecosystem functioning is unusual: microbial decomposition is inhibited because the leaves are sclerophyllous and toxic to deter herbivory in the nutrient poor environment, yet bacteria are abundant and active in the surface layers of the peat, where they respire DOC leached from newly fallen leaves. The bacteria are subsequently consumed by aquatic invertebrates that are eaten by Wsh, and bacterially respired CO 2 is assimilated by algae, so bacteria are thus vital to carbon and nutrient cycling. Peat swamp forests are highly sensitive to the impacts of logging, drainage and Wre, due to the interdependence of the vegetation with the peat substrate, which relies on the maintenance of adequate water, canopy cover and leaf litter inputs. Even minor disturbances can increase the likelihood of Wre, which is the major cause of CO 2 emissions from regional peat swamp forests and which impact ecosystems worldwide by contributing to climate change. Indo-Malayan peat swamps aVect the hydrology of surrounding ecosystems due to their large water storage capacity which slows the passage of Xoodwaters in wet seasons and maintains stream base Xows during dry seasons. These forests are of global importance yet they are inadequately protected and vanishing rapidly, particularly due to agricultural conversion to oil palm, logging, drainage and annual Wres.