The presence of peat and variation in tree species composition are under different hydrological controls in Amazonian wetland forests

The peat-forming wetland forests of Amazonia are characterized by high below-carbon stocks and supply fruit, fibres timber to local communities. Predicting the future these ecosystem services requires understanding how hydrological conditions related tree species composition presence, or absence, peat. Here, we use continuous measurements water table depth over 2.5 years manual pore-water pH electrical conductivity understand ecohydrological controls variables across large peatland complex in northern Peruvian Amazonia. Measurements were taken permanent forest plots four palm swamps, seasonally flooded pole forests. All trees ≥10 cm diameter also measured identified assess floristic composition. Peat occurs eight twelve sites; three one swamp not associated with Variation among types was linked flood levels (maximum flooding height) pH: experience (up 3.66 m from ground surface) have values (6–7), swamps intermediate 1.34 m) shallow 0.28 low (4). In contrast, presence peat variation maximum (i.e. which drops below surface). Surface is found all where does fall >0.55 surface at any time. formation therefore different controls. Predicted increases frequency strength events may alter patterns composition, whereas drought severity declines minimum river pose a greater risk belowground carbon stores ecosystems.