Carbon storage values in the Amazon basin have been studied through different approaches in the last decades in order to clarify whether the rainforest ecosystem is likely to act as a sink or source for carbon in the near future. This water balance, dissolved organic carbon (DOC) and nutrient export study were carried out in a micro-scale heath forest (Campina) catchment in central Amazonia, Brazil. For a 1-year study period (18 March 2007 until 19 March 2008), rainfall amounted to 3054mm; of which, 1532mm was evaporated by the forest (4.1mmday-1). Rainfall interception loss amounted to 15.6% of gross rainfall. Surface runoff amounted to 485mm, whereas another 1071mm was discharged as regional groundwater outflow. Accumulated DOC exports in surface runoff amounted to 15.3gm-2year-1, whereas the total carbon exported was 55.9gm-2. This is much higher than that observed for a nearby tall rainforest catchment in central Amazonia (DOC export<20gm-2). As Campina heath forest areas cover a significant proportion of the Amazon Basin, these differences in ecosystem hydrological carbon exports should be taken into account in future studies assessing the carbon budget for the Amazon Basin. Macro-nutrient exports were low, but those of calcium and potassium were higher than those observed for tall rainforest in the Amazon, which may be caused by a lower retention capacity of the heath forest ecosystem. © 2015 John Wiley & Sons, Ltd.
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