Figure 2.

(A) Box plot of δ¹³C values in fish collected from the Pearl River Estuarine (PRE) and the middle of the South China Sea (MSCS). The cyan and brown areas represent the range of δ¹³C values in marine plankton and terrestrial plankton reported by previous works [52,53]. (B) Box plot of δ¹⁵N values in fish collected from the PRE and the MSCS. The dashed lines of cyan and brown represent the baseline δ¹⁵N in phytoplankton collected from the MSCS and the PRE, respectively.*** represents that the data are significantly different between the PRE and the MSCS (p < 0.001).