Reviews and syntheses: <sup>210</sup>Pb-derived sediment and carbon accumulation rates in vegetated coastal ecosystems: setting the record straight

Abstract

Abstract. Vegetated coastal ecosystems, including tidal marsh, mangrove and seagrass, are being increasingly assessed for their potential in carbon dioxide sequestration worldwide. However, there is a paucity of studies that have effectively estimated the accumulation rates of sediment organic carbon (C org ) beyond the mere quantification of C org stocks. Here, we discuss the use of the 210 Pb dating technique as a practical tool to measure the rate of C org accumulation in vegetated coastal ecosystems. We critically review the status of

Controls on Sediment Accretion and Blue Carbon Burial in Tidal Saline Wetlands: Insights From the Oregon Coast, USA

“…The CIC method was chosen over other models for analyzing excess 210 Pb‐derived accumulation rates, specifically the constant‐flux‐constant sedimentation or constant rate of supply models, as it is a straightforward and widely used model (e.g., Callaway et al, ; Mudd et al, ). Based on the downcore profiles of excess 210 Pb decay (Figure S2), it seems that the assumptions of the CIC model, specifically that the initial excess 210 Pb activity at the sediment surface is constant and that excess 210 Pb activity monotonically decreases with depth (Arias‐Ortiz et al, ), are met.…”

Evaluating the historical sedimentation patterns in two different Mediterranean deep environments (Sardinia and Sicily Channels)

“…3). Indeed, the percentage of sandy particles in the upmost layer of the SC-1 core is 50% versus 30% in the SC-2 core, which could result in enhancing 210 Pb content due to its high affinity to finer particles (Mejjad et al, 2016;Arias-Ortiz et al, 2018;Fontela et al, 2019). The vertical profiles shown in Figure 3 indicate a predominance of mud content and some degree of fluctuations in the upper layers, in particular in the SC-1 core.…”

serac: an R package for ShortlivEd RAdionuclide chronology of recent sediment cores

“…The 210 Pbex activity follows an exponential decay (characterised by its half-life t1/2= 22.3 years) from which it is possible to calculate the sedimentation rate for the past 100 to 150 years (~5 x t1/2). Several models to infer ages from 210 Pbex decay have been recently proposed (Appleby, 2008(Appleby, , 2001Appleby and Oldfield, 1992;Arias-Ortiz et al, 2018;Sanchez-Cabeza and Ruiz-Fernández, 2012) and several limitations have been described (Baskaran et al, 2014;Binford, 1990;Cooke et al, 2010;Kirchner, 2011). These isotopes are also used in chronologies from corals (Andrews et al, 2009;Druffel et al, 1990;Moore and Krishnaswami, 1972;Sabatier et al, 2012) and speleothems (Baskaran and Iliffe, 1993;Condomines and Rihs, 2006) through excess or ingrowth methods.…”