In 2010, dry-season rainfall was low across Amazonia, with apparent similarities to the major 2005 drought. We analyzed a decade of satellite-derived rainfall data to compare both events. Standardized anomalies of dry-season rainfall showed that 57% of Amazonia had low rainfall in 2010 as compared with 37% in 2005 (≤–1 standard deviation from long-term mean). By using relationships between drying and forest biomass responses measured for 2005, we predict the impact of the 2010 drought as 2.2 × 1015 grams of carbon [95% confidence intervals (CIs) are 1.2 and 3.4], largely longer-term committed emissions from drought-induced tree deaths, compared with 1.6 ×1015 grams of carbon (CIs 0.8 and 2.6) for the 2005 event.
Effects of partial throughfall exclusion on the phenology of Coussarea racemosa (Rubiaceae) in an east-central Amazon rainforest
Severe droughts may alter the reproductive phenology of tropical tree species, but our understanding of these effects has been hampered by confounded variation in drought, light and other factors during natural drought events. We used a large-scale experimental reduction of throughfall in an easterncentral Amazon forest to study the phenological response to drought of an abundant subcanopy tree, Coussarea racemosa. We hypothesized that drought would alter the production and the timing of reproduction, as well as the number of viable fruits.