Regional wetland distributions and methane emissions in the Amazon basin John Melack and Laura Hess University of California, Santa Barbara Bruce Forsberg and Lauren Belger INPA

Amazon Basin below 500m: wetlands 17%, uplands 83%

high-water 48°W 16°S 4°N4°N 78°W Water Bare or herbaceous, non-flooded Herbaceous, flooded Shrub, non-flooded Shrub, flooded Woodland, flooded Forest, non-flooded Forest, flooded

low-water 48°W 16°S 4°N4°N 78°W Water Bare or herbaceous, non-flooded Herbaceous, flooded Shrub, non-flooded Shrub, flooded Woodland, flooded Forest, non-flooded Forest, flooded

Flooded forest, woodland and shrubs Upper and lower left: high water Lower right: low water

Aquatic macrophytes Upper and lower left: high water Lower center and right: low water

Wetlands Mapping: Thematic Accuracy Zones I I I II III IV

Wetlands Mapping: Thematic Accuracy Zones I I I II III IV For wetland vs. non-wetland mapping, primary validation dataset is 1999 videography (timed to high-water stage for central Amazon) Zone 1 is a 500 km buffer centered along 1999 video flightlines Within Zone 1, we assume video-based accuracy statistics are valid  To what extent can these results be extended beyond Zone 1?

Wetlands Mapping: Thematic Accuracy Zones I I I II III IV Zone II: vegetation structure and flood timing are represented within video transects Zone III: flood timing not well represented within video transects Zone IV: neither vegetation nor flood timing well represented within video transects

Amazon basin Major river channels derived from Coe, et al Rivers above 500m elevation or outside study area excluded 4°N4°N 78°W 48°W 16°S

4°N4°N 78°W 48°W 16°S Red: more flooding in October Cyan: more flooding in March White: same flooding in October and March 1996 Michael Coe 2008 unpublished modeled inundation

4°N4°N 78°W 48°W 16°S Red: more flooding in September Cyan: more flooding in June White: same flooding in September and June 1996 Michael Coe 2008 unpublished modeled inundation

Habitat areas Lowland basin BasinwideNegroMadeiraMojos savanna River channel3% Open water5%8%6%5% Herbaceous13%7%34%43% Forest/Shrubs79%85%61%52%

Evasion of methane Melack et al Global Change Biology 10: Remotely-sensed estimates of seasonally of inundation and wetland vegetation Measurements of methane emission from wetland habitats (open water, flooded forests and floating macrophytes)

Uncertainty Analysis Uncertainties in the regional emission rates were determined by Monte Carlo error analyses that combined error estimates for the measurements of emission and for calculations of inundation and habitat areas.

Mean Area uncertainty Methane emission from Solimoes-Amazon floodplain Minimum, mean and maximum inundation (Sippel et al. 1998) with one standard error in methane emission from Devol et al. (1990)

Methane emission for lowland basin Gg C day -1 Low-waterHigh-water mean  stdev mean  stdev River channel Open water floodplain Flooded herbaceous Flooded woody Un-flooded, any habitat 00 Total 2466

Basinwide annual total = 16 Tg C Tg C Basinwide monthly methane emissions

Negro River basin Water Bare or herbaceous, non-flooded Herbaceous, flooded Shrub, non-flooded Shrub, flooded Woodland, flooded Forest, non-flooded Forest, flooded 78°W, 4°N 60°W, 3°S

Upper Negro savannas

Upper Negro (RNL)

Methane emission for Rio Negro basin Gg C day -1 Basin averageRioNegro LowHighLowHigh River channel Open water floodplain Flooded herbaceous Flooded woody Un-flooded, any habitat 0000 Total

Research Needs Process-based models Ecological studies and methane emission measurements Seasonally flooded savannas Floodplains in eastern Peru Freshwater wetlands in Amazon delta Riparian zones of streams