Low carbon accumulation in a macro‐tidal mangrove forest on the Amazon coast

The important role mangrove forests play in sequestering organic carbon is well known, yet rates of accumulation macro-tidal ecosystems are poorly resolved. Here we use 210Pb dating to present a 125-yr record carbon, nutrient and trace metal sediments from an Amazon forest. We find that the rate ranged 23.7 74.7 g m−2 yr−1 (average 38 ± 13.5 yr−1), significantly lower than global averages for forests. These low may be associated with sediment grain-size sediment–water interface processes drive matter oxidation reduce stocks these highly dynamic Total nitrogen 1.4 5.1 2.7 0.9 yr−1) phosphorus 1.5 8.4 yr−1(average 4.3 1.9 yr−1). Trace (As, Pb, Cr, Cu, Mn, Ni, Zn, Hg, Bo, V, Co, Mo, S, Ba) were also other tropical globally, but more recent As, Hg elevated, likely reflecting human footprint region since early 20th century. ability accurately quantify critical climate change mitigation strategies implementation offset schemes globally.