Bian Xiaopeng

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Last Name
Bian
First Name
Xiaopeng
ORCID
0000-0002-6098-7324

Search Results

Now showing 1 - 5 of 5
  • Dataset
    Dissolved concentrations of nickel and copper from bottle samples collected on Leg 2 (Hilo, HI to Papeete, French Polynesia) of the US GEOTRACES Pacific Meridional Transect (PMT) cruise (GP15, RR1815) on R/V Roger Revelle from October to November 2018
    (Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2022-12-19) Bian, Xiaopeng ; Yang, Shun-Chung ; John, Seth G.
    This dataset contains dissolved concentrations of nickel (Ni) and copper (Cu) from bottle samples. The samples were collected during the U.S. GEOTRACES PMT cruise aboard the R/V Roger Revelle (RR1815 from October 24th to November 23rd of 2018). The dataset also includes station number, date, time, latitude, longitude, event number, event description, sample number, depth, and data quality flag. The data from Leg 1 of this transect, RR1814, are available as a related dataset. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/885335
  • Dataset
    Dissolved concentrations of nickel and copper from bottle samples collected on Leg 1 (Seattle, WA to Hilo, HI) of the US GEOTRACES Pacific Meridional Transect (PMT) cruise (GP15, RR1814) on R/V Roger Revelle from September to October 2018
    (Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2022-12-19) Bian, Xiaopeng ; Yang, Shun-Chung ; John, Seth G.
    This dataset contains dissolved concentrations of nickel (Ni) and copper (Cu) from bottle samples. The samples were collected during the U.S. GEOTRACES PMT cruise aboard the R/V Roger Revelle (RR1814 from September 18th to October 21st of 2018). The dataset also includes station number, date, time, latitude, longitude, event number, event description, sample number, depth, and data quality flag. The data from Leg 2 of this transect, RR1815, are available as a related dataset. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/885319
  • Preprint
    Actinium and radium fluxes from the seabed in the northeast Pacific Basin
    (Elsevier, 2022-10-22) Kemnitz, Nathaniel ; Hammond, Douglas E. ; Henderson, Paul ; Le Roy, Emilie ; Charette, Matthew ; Moore, Willard ; Anderson, Robert F. ; Fleisher, Martin Q. ; Leal, Anne ; Black, Erin ; Hayes, Christopher T. ; Adkins, Jess ; Berelson, William ; Bian, Xiaopeng
    Five sediment cores were collected along a cruise tract from Hawaii to Alaska in August 2017 (C-Disk-IV cruise) with the objective of characterizing the behavior of 227Ac, 228Ra, and 226Ra and their fluxes into the overlying water column, information that is essential to the interpretation of the distribution of these tracers in the ocean, for example, as measured on GEOTRACES cruises. Solid phase profiles of these isotopes were measured, and reaction-transport models were applied that incorporated molecular diffusion, bioturbation, sedimentation, distribution coefficients (kd), and the fraction of each isotope released to pore water by parent decay (called F). Fits to these profiles used kd values determined in lab experiments for C-Disk-IV sediments. Ra kd values (1000–3000 mL g−1) agreed with previous estimates for deep-sea sediments, and Ac kd values (3500–22,000 mL g−1) correlated with those for Ra but were about 7 times greater. Two independent approaches were used to quantify the benthic fluxes of 227Ac and 228Ra in the Northeast Pacific: (1) use of solid phase profiles with a reaction-transport model, as well as integrated downcore daughter-parent deficiency; and (2) direct measurement of fluxes based on core incubation. The two independent methods agreed within uncertainty, and the average 227Ac and 228Ra sediment fluxes for the Northeast Pacific are 90 ± 20 and 600 ± 200 dpm m−2-yr−1, respectively. The 226Ra sediment flux was only determined by the former approach, and the flux calculated in this study is similar to previous work in the North Pacific, averaging 1300 ± 200 dpm m−2-yr−1. This is over 2× higher than the water column inventory of 226Ra in this region (600 dpm m−2-yr−1), and indicates the importance of lateral 226Ra export from the N. Pacific. The largest 227Ac and Ra isotope fluxes in the study area are near the center of the Northeast Pacific (∼37°N). Smaller 227Ac, 228Ra and 226Ra fluxes occur north of 40°N, primarily due to dilution of their Pa and Th ancestors by higher sediment accumulation rates.
  • Article
    Recycling of dissolved iron in the North Pacific Subtropical Gyre
    (Association for the Sciences of Limnology and Oceanography, 2022-09-08) Hawco, Nicholas J. ; Yang, Shun-Chung ; Pinedo-Gonzalez, Paulina ; Black, Erin E. ; Kenyon, Jennifer ; Ferrón, Sara ; Bian, Xiaopeng ; John, Seth G.
    The importance of iron as a limiting nutrient in the open ocean is widely recognized, but there is substantial uncertainty about the rate that it cycles in the marine environment. Here, we combine measurements from the water column, sediment traps, and incubations to constrain Fe turnover during summer at Station ALOHA in the North Pacific Subtropical Gyre. Using low levels of 57Fe–58Fe double spike, measured with high precision by multi-collector inductively coupled plasma mass spectrometry, we find Fe uptake rates of 30–60 pM d−1 throughout the euphotic zone. Dissolved Fe turnover times are estimated at 10–15 d in the mixed layer and 1–3 d near the deep chlorophyll maximum. Aerosol Fe supply inferred from a thorium isotope mass balance indicates that the dissolved Fe residence time is approximately 6 months in the upper euphotic zone (0–75 m), relative to external sources, and 2 months in the lower euphotic zone (75–150 m). To reconcile these observations, the average Fe atom must be recycled over 25 times at Station ALOHA in both the upper and lower euphotic zones (an “Fe ratio” equal to 0.04 and 0.03, respectively), a level of conservation that has only been documented in Fe-limited regions thus far. At steady state, this scenario requires an aerosol Fe solubility of 4.5%, which is similar to dissolution experiments from Pacific Ocean aerosols. Our results suggest that the oligotrophic ocean is capable of recycling iron efficiently even when these ecosystems are not demonstrably iron-limited.
  • Dataset
    Concentrations of dissolved cadmium, nickel, manganese, lanthanum, cerium, praseodymium, and neodymium from the Eastern Tropical North Pacific Ocean on R/V Revelle cruise RR1804-1805 (OMZ Nutrient Cycling project)
    (Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2022-05-27) John, Seth G. ; Bian, Xiaopeng ; Moffett, James W.
    Oxygen deficient zones (ODZs) play an important role in the distribution and cycling of trace metals in the ocean, as important sources of metals including Fe and Mn to the ocean, and also as possible sinks of chalcophile elements such as Cd. The Eastern Tropical North Pacific (ETNP) ODZ is one of the three largest ODZs worldwide. Here we present results from two sectional surveys through the ETNP ODZ (23N-14N, 105W-130W) conducted during two cruises of the R/V Roger Revelle, RR1804 and RR1805, from March to April 2018, providing a high-resolution concentrations of dissolved Cd, Ni, Mn, La, Ce, Pr, and Nd in seawater. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/872434