Carbon sequestration and geochronology in Southern England’s seagrass meadows

Abstract

The aim of this study was to provide an evaluation of the current methods used to assess carbon sequestration (C_seq) rates from intertidal Zostera spp. meadows in central Southern England. This study evaluated the use of ²¹⁰Pb dating methods to calculate sediment accretion rates from four intertidal seagrass meadows along the southern central coast of England. Results obtained were then used to determine C_seq rates, following different models. The mean rate of C_seq calculated in this study using the CRS model was 75.12 g m^-2 year^-1, comparable to other global regions and within the estimated global range. However, results revealed that other, conservative methods, provide much lower C_seq rates, highlighting the need for caution when choosing appropriate methods and reporting results related to seagrass carbon sequestration potential. Moreover, these results highlight the importance of local assessments of C_seq, and the need to create robust models that include the effects of mixing, erosion, and disturbance, to better understand the possible effects of extreme climate events and anthropogenic impacts on seagrass ecosystems' carbon sequestration potential.

Keywords

Seagrass / blue carbon / carbon sequestration / sediment accretion / ²¹⁰Pb

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