Description: We investigated the responses of elemental stoichiometry (POC, PON) and sterol contents (brassicasterol, dinosterol) in three dinoflagellate species (Prorocentrum donghaiense, Prorocentrum minimum and Karenia mikimotoi) to changes in temperatures (15, 20 and 25 °C), N:P supply ratios (molar ratios 10:1, 24:1 and 63:1) in the exponential phase in batch culture experiments.

Description: Continental margin ecosystems in the western North Pacific Ocean are subject to strong climate forcing and anthropogenic impacts. To evaluate mechanisms controlling phytoplankton biomass and community structure variations in marginal sea-open ocean boundary regions, brassicasterol, dinosterol and C37 alkenones were measured in suspended particles in summer and autumn from 2012 to 2013 in the northeastern East China Sea and the western Tsushima Strait (NEECS-WTS). In summer, the concentrations of brassicasterol (40 - 1535 ng L-1) and dinosterol (4.2 - 94 ng L-1) were higher in the southwest of Cheju Island, while C37 alkenones (0 - 30 ng L-1) were higher in the south of Cheju Island. In autumn, brassicasterol (12 - 106 ng L-1), dinosterol (2.4 - 21 ng L-1) and C37 alkenones (0.7 - 7.0 ng L-1) were higher in the southwest of Cheju Island and the WTS, and higher C37 alkenones also occurred in the Okinawa Trough. Correlation analysis of biomarkers and environmental conditions (temperature, salinity and inorganic nutrient concentrations) clearly demonstrated that phytoplankton biomass and community structure variations can be well elucidated by water masses as indexed by temperature and salinity. High nutrients from the Changjiang River were the main cause of high biomass in summer, while nutrients from subsurface water were likely the key factor regulating phytoplankton biomass in open ocean water stations in autumn. This study indicates that mechanisms controlling phytoplankton biomass in marginal sea-open ocean boundary regions should be classified by various water masses with different nutrient concentrations, instead of by geography.

Description: This dataset comprises new data and previously published data on marine lipid biomarkers (brassicasterol, dinosterol, C37 alkenones, and the sum of them [∑PB]) in surface suspended particles at 334 stations from seven cruises between 2010 and 2015, and in surface sediments at 258 stations from eight cruises between 2006 and 2012 in the eastern China marginal seas (ECMS). Of all marine lipid biomarker data, 107 surface suspended particle samples were newly measured, with 227 surface suspended particle samples and 258 sediment samples previously published. We also provide the following oceanographic data, most of which were collected from published results (as described in the publication): sea surface temperature (SST, n = 273, from five cruises in summer of 2010–2015), salinity (n = 273, from five cruises in summer of 2010–2015), nutrient concentrations (dissolved inorganic nitrogen [DIN], dissolved inorganic phosphorus [DIP] and silicate [Si]) (n = 133, from three cruises in summer of 2011 and 2015) and Chl a (chlorophyll a, n = 229, from five cruises in summer of 2010–2014) in the surface water, as well as terrestrial biomarker [∑(C27 + C29 + C31) n-alkanes] contents (n = 226), TOC (total organic carbon content, n = 200), δ13CTOC (stable carbon isotope values for TOC, n=269), and sedimentation rate (n = 220) in surface sediments. Some data were measured using in situ CTD instrument in this study: sea surface temperature and salinity in the East China Sea in June 2010 and July 2013 (n = 54), and Chl a in the Changjiang River Estuary in August 2015 (n = 33). The contents of ∑(C27 + C29 + C31) n-alkanes in the southern Yellow Sea in April 2012 (n = 32) were also newly measured. The surface suspended particle samples were obtained by filtering on Whatman GF/F filters, and the surface sediments were collected by multiple corers or stainless-steel grab samplers. Marine and terrestrial lipid biomarkers were analyzed by gas chromatograph (Agilent 6890N) according to the method in Zhao et al. 2006 (doi: 10.1016/j.orggeochem.2005.08.022) and Wu et al. 2016 (doi: 10.1002/2015JG003167). The study resulting from this analysis has been published in Frontiers in Marine Science (doi:10.3389/fmars.2022.824181).