Four decades' dynamics of coastal blue carbon storage driven by land use/land cover transformation under natural and anthropogenic processes in the Yellow River Delta, China

Land reclamation can impact a variety of ecosystem services provided by coastal wetlands. The dynamics of coastal blue carbon storage (CBCS) altered by land use/land cover (LULC) transformation and its linkage with natural and anthropogenic driving processes was analyzed in the Yellow River Delta (YRD), China. Using LULC data in the YRD during 1970-2010, the LULC transformation in four periods (i.e., 1970-1980, 1980-1990, 1990-2000 and 2000-2010) and their cumulative conversions within coastal wetlands were tracked to investigate the flow of LULC transformation. The spatiotemporal dynamics of the CBCS were then modeled and investigated by InVEST based on the LULC transformation in relation to their driving processes. The results indicated that the CBCS in the YRD has been substantially altered by continuous LULC transformation driven by the natural and anthropogenic processes, totally decreased by 10.2% (1.63 × 10⁶ Mg) during 1970-2010 followed the loss of 2028 km² natural wetlands converted to socioeconomic land use. The 78% of increased CBCS were contributed by single natural (e.g., succession) or anthropogenic (e.g., restoration) driving process at the seaward edge within tidal area, whereas 71% of decreased CBCS was linked with multiple driving processes in inland areas. In addition, the anthropogenic driving processes caused much greater loss (-5.97 × 10⁵ Mg) than gain (6.81 × 10⁴ Mg) in CBCS, compared with a net gain of CBCS (1.04 × 10⁴ Mg) brought by the natural driving processes. The study can facilitate to develop coastal management strategy to balance and mitigate the conflicted LULC between socioeconomic development and maintenance of multiple ecosystem services incorporating CBCS.