Fuente: PubMed "Ecological production" Mar Environ Res. 2025 Sep 4;212:107523. doi: 10.1016/j.marenvres.2025.107523. Online ahead of print.ABSTRACTThe northern South China Sea (SCS) shelf and southern Taiwan Strait (TS) are dynamic marginal seas influenced by both freshwater discharge from the Pearl River and seasonal coastal upwelling. These interacting hydrological forces shape ecological gradients that affect marine planktonic communities. Planktonic foraminiferal assemblages were analyzed from plankton tow and surface sediment samples collected during three cruises (2018, 2020, and 2022) along a ∼1000 km transect extending from the Pearl River estuary to the southern TS. Species composition, stable isotopes (δ13C and δ18O), and empirical orthogonal function (EOF) analysis were used to assess spatiotemporal patterns. Results show that Globigerinoides ruber, indicating nutrient conditions from the plume, suggests its influence is largely restricted to nearshore areas, whereas upwelling-associated species, including Globigerina bulloides, dominate toward the shelf edge and indicate that upwelling on the Taiwan Banks (TB) may start as early as spring. Differences between sediment and plankton assemblages indicate potential time lags between ecological production and sedimentary deposition. The EOF analysis identified water depth as the primary spatial control on species composition, followed by the combined influence of riverine input and upwelling. This statistical approach helps separate spatial controls and disentangle overlapping environmental drivers shaping assemblage variability. Based on TB observations, the δ13C and δ18O values of Trilobats sacculifer respond rapidly to upwelling conditions, underscoring its utility as a regionally sensitive proxy for biogeochemical processes. These findings reveal the coupled influence of terrestrial and oceanic forces and support the use of foraminiferal assemblages for environmental reconstructions in subtropical marginal seas.PMID:40915280 | DOI:10.1016/j.marenvres.2025.107523