@article {2700,
	title = {Carbon Cycling in the World{\textquoteright}s Deepest Blue Hole},
	journal = {Journal of Geophysical Research: Biogeosciences},
	volume = {125},
	year = {2020},
	month = {Jan-02-2020},
	abstract = {Blue holes are unique geomorphological features with steep biogeochemical gradients and distinctive microbial communities. Carbon cycling in blue holes, however, remains poorly understood. Here we describe potential mechanisms of dissolved carbon cycling in the world{\textquoteright}s deepest blue hole, the Yongle Blue Hole (YBH), which was recently discovered in the South China Sea. In the YBH, we found some of the lowest concentrations (e.g., 22 μM) and oldest ages (e.g., 6,810 years before present) of dissolved organic carbon, as well as the highest concentrations (e.g., 3,090 μM) and the oldest ages (e.g., 8,270 years before present) of dissolved inorganic carbon observed in oceanic waters. Sharp gradients of dissolved oxygen, H2S, and CH4 and changes in bacterially mediated sulfur cycling with depth indicated that sulfur- and/or methane-based metabolisms are closely linked to carbon cycling in the YBH. Our results showed that the YBH is a unique and easily accessible natural laboratory for examining carbon cycling in anoxic systems, which has potential for understanding carbon dynamics in both paleo and modern oceans{\textemdash}particularly in the context of global change.},
	keywords = {anoxia, carbon cycling, dissolved carbon, radiocarbon, sulfur cycling, Yongle blue hole},
	issn = {2169-8953},
	doi = {10.1029/2019JG005307},
	url = {https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019JG005307},
	author = {Yao, P. and Wang, X. C. and Bianchi, T. S. and Yang, Z. S. and Fu, L. and Zhang, X. H. and Chen, L. and Zhao, B. and Morrison, E. S. and Shields, M. R. and Liu, Y. N. and Bi, N. S. and Qi, Y. Z. and Zhou, S. and Liu, J. W. and Zhang, H. H. and Zhu, C. J. and Yu, Z. G.}
}
@article {467,
	title = {Changes in sediment and organic carbon accumulation in a highly-disturbed ecosystem: The Sacramento-San Joaquin River Delta (California, USA)},
	journal = {Marine Pollution Bulletin},
	volume = {59},
	year = {2009},
	note = {id: 1845; Sp. Iss. SI 477XX Times Cited:1 Cited References Count:49Y},
	pages = {154-163},
	abstract = {We used the Sacramento-San Joaquin River Delta CA (Delta, hereafter) as a model system for understanding how human activities influence the delivery of sediment and total organic carbon (TOC) over the past 50-60 years. Sediment cores were collected from sites within the Delta representing the Sacramento River (SAC), the San Joaquin River (SJR), and Franks Tract (FT), a flooded agricultural tract. A variety of anthropogenic tracers including (CS)-C-137, total DDE (Sigma DDE) and brominated diphenyl ether (BDE) congeners were used to quantify sediment accumulation rates. This information was combined with total organic carbon (TOC) profiles to quantify rates of TOC accumulation. Across the three sites, sediment and TOC accumulation rates were four to eight-fold higher prior to 1972. Changes in sediment and TOC accumulation were coincident with completion of several large reservoirs and increased agriculture and urbanization in the Delta watershed. Radiocarbon content of TOC indicated that much of the carbon delivered to the Delta is "pre-aged" reflecting processing in the Delta watershed or during transport to the sites rather than an input of predominantly contemporary carbon (e.g., 900-1400 years BP in surface sediments and 2200 yrs BP and 3610 yrs BP at the base of the SJR and FT cores, respectively). Together, these data suggest that human activities have altered the amount and age of TOC accumulating in the Delta since the 1940s. (C) 2009 Elsevier Ltd. All rights reserved.},
	issn = {0025-326X},
	doi = {10.1016/j.marpolbul.2009.03.025},
	author = {Canuel, E. A. and Lerberg, E. J. and Dickhut, R. M. and Kuehl, S. A. and Bianchi, T. S. and Wakeham, S. G.}
}
@article {478,
	title = {Partitioning of organic matter in continental margin sediments among density fractions},
	journal = {Marine Chemistry},
	volume = {115},
	year = {2009},
	note = {id: 1844; 521ZI Times Cited:0 Cited References Count:99Y},
	pages = {211-225},
	abstract = {Hydrodynamic processes sort and redistribute organic matter (OM) and minerals on continental margins. Density fractionations were conducted on sediments from diverse margins (Mexico margin, Gulf of Mexico, Mississippi River delta, Eel River margin) to investigate the nature, provenance and age of OM among density fractions. Mass. elemental (C and N), lignin, and surface area distributions, as well as stable carbon and radiocarbon isotopic compositions were measured, The lowest density fractions (2.5 g cm(-3)) were OC-poor (\%OC -200 parts per thousand). Ratios of vanillic acid to vanillin (Ad/Al)v among lignin oxidation products increase with increasing particle density suggesting variable lignin sources or selective degradation of lignin among the different density fractions. (C) 2009 Elsevier B.V. All rights reserved.},
	issn = {0304-4203},
	doi = {10.1016/j.marchem.2009.08.005},
	author = {Wakeham, S. G. and Canuel, E. A. and Lerberg, E. J. and Mason, P. and Sampere, T. P. and Bianchi, T. S.}
}
@article {481,
	title = {Photochemical changes in chemical markers of sedimentary organic matter source and age},
	journal = {Marine Chemistry},
	volume = {113},
	year = {2009},
	note = {id: 793; 425QO Times Cited:0 Cited References Count:40Y},
	pages = {123-128},
	abstract = {Several chemical markers of organic matter source and age are shown to be susceptible to light-induced alteration. To test for the photochemical lability of markers previously employed for sediments from the Louisiana Coastal zone, we subjected sediments under resuspension conditions to Simulated Sunlight, and monitored changes in ON and Br:OC ratios, delta C-13, Delta C-14, and lignin composition. Markers of terrigenous origin (high C:N, lignin) decreased and delta C-13 became enriched in sediments containing primarily terrigencrus organic matter, while a marker of marine organic matter (Br:OC) decreased in samples containing significant contributions from this source. Preferential loss of C-14 from all sediments indicated enhanced photochemical lability of organic matter of relatively recent origin, consistent with the changes in chemical markers. Most, but not all, experimental alterations are consistent with field distributions of these markers. Relatively small experimental changes in the markers in combination with confounding processes in the environment, however. prevent these parallel trends from providing any more than a consistency test for the importance of photochemical reactions in this region. (C) 2009 Elsevier B.V. All rights reserved.},
	issn = {0304-4203},
	doi = {10.1016/j.marchem.2009.01.006},
	author = {Mayer, L. M. and Schick, L. L. and Bianchi, T. S. and Wysocki, L. A.}
}
