Wen-Chen Chou

• National Taiwan Ocean University

Seagrass meadows are increasingly recognized across the globe as a natural climate solution due to their significant potential in alkalinity‐driven carbon dioxide (CO2) removal, which possibly represents an overlooked component of ocean carbon removal. This study comprehensively investigated the carbonate chemistry, sediment carbon content, mineral...

Seagrass meadows are vital carbon sinks, but their function is threatened by rapid decline, driving restoration efforts to enhance coastal recovery and carbon removal. The capacity of these restored seagrass as carbon sources or sinks depends largely on organic carbon metabolism and carbonate dynamics. In this study, we employed ex situ core incuba...

The shallow-sea hydrothermal vent at Guishan Islet, located off the coast of Taiwan, serves as a remarkable natural site for studying microbial ecology in extreme environments. In April 2019, we investigated the composition of prokaryotic picoplankton communities, their gene expression profiles, and the dissolved inorganic carbon uptake efficiency....

Coastal blue carbon ecosystems sequester carbon, storing it as plant biomass and particulate organic matter in sediments. Recent studies emphasize the importance of incorporating dissolved inorganic and organic forms into carbon assessments. As sediment-stored organic matter decomposes, it releases dissolved inorganic carbon (DIC) and total alkalin...

This study aimed to comprehend the effects of Typhoon Maria on the pelagic ecosystem in the southern East China Sea. Shipboard measurements were conducted at eight sampling stations before (2–4 d) and after (3–6 d) the typhoon, which enabled the evaluation of the potential impacts of the typhoon on this pelagic ecosystem, with particular focus on c...

Coral reefs are facing threats from a variety of global change stressors, including ocean warming, acidification, and deoxygenation. It has been hypothesized that growing corals near primary producers such as macroalgae or seagrass may help to ameliorate acidification and deoxygenation stress, however few studies have explored this effect in situ....

The ocean is the planet’s largest carbon reservoir and plays a crucial role in regulating atmospheric CO2 levels, especially in the face of climate change. In coral reef ecosystems, understanding the carbonate system is critical for predicting and mitigating the impact of ocean acidification on these vulnerable marine ecosystems, especially as atmo...

There is no doubt that seagrass beds constitute one of the most productive ecosystems in shallow coastal waters. Despite this, picoplankton in seagrass ecosystems has received relatively little attention. The purpose of this study was to compare picoplankton growth and mortality rates between seagrass and unvegetated habitats using chamber incubati...

There is no doubt that seagrass beds constitute one of the most productive ecosystems in shallow coastal waters. Despite this, picoplankton in seagrass ecosystems has received relatively little attention. The purpose of this study was to compare picoplankton growth and mortality rates between seagrass and unvegetated habitats using chamber incubati...

A seagrass meadow is one of the most important ecosystems around the world, both economically and ecologically. An important feature of this ecosystem is the presence of large coastal seagrass beds, which dominate the primary production and contribute to the secondary productivity of the ecosystem. The microbial loop (consuming bacterial biomass by...

In coastal areas around the world, seagrass meadows play a crucial ecological and economic role. A large amount of seagrass beds dominates primary production and contributes to the high secondary productivity of this ecosystem. The microbial loop (consuming bacterial biomass by grazers and using seagrass-derived detritus by bacteria) may be an impo...

Although we have gained insight into the biological and biochemical effects of natural sunlight exposure on prokaryotes, little is known about sunlight exposure on natural virus communities. To address this question, an investigation of the effects of sunlight and dark treatments on viral communities, viral production and decay rates in Kenting coa...

Ocean deoxygenation is predicted to threaten marine ecosystems globally. However, current and future oxygen concentrations and the occurrence of hypoxic events on coral reefs remain underexplored. Here, using autonomous sensor data to explore oxygen variability and hypoxia exposure at 32 representative reef sites, we reveal that hypoxia is already...

Upwelling regions, which account for 10%–20% of the global ocean's primary production but occupy only 3% of its area, play an important role in the global ocean carbon cycle. However, controlling factors of the partial pressure of carbon dioxide (pCO2) in upwelling regions before and after typhoons remain unclear. Sea surface pCO2 was measured in t...

Dissolved oxygen (DO) and partial pressure of CO2 (pCO2) were measured at half-hourly intervals from June 29 to September 9, 2019, in a seagrass meadow in the Southeast Asia archipelagos region. The open water mass balance of the O2 approach was used to calculate metabolic rates (i.e., gross primary production (GPP), community respiration (CR), and...

Although we have gained insight into the biological and biochemical effects of natural sunlight exposure on prokaryotes, little is known about sunlight exposure on natural virus communities. To fully understand the mechanics of microbial food webs, it is essential to understand the dynamics of viral infection of bacteria and its role in bacteria-me...

In this study, two cruises were conducted across the mainstream of the Kuroshio off eastern Taiwan before and after the passage of Typhoon Saola in summer 2012. The continuous underway pCO2 (i.e., partial pressure of CO2) measurements revealed that surface seawater pCO2 (SS pCO2) displayed spatial variations in response to typhoon passage. The simu...

Hypoxia and upwelling co-occur in the summer, and well-mixed water typically reaches the subsurface in the East China Sea (ECS), especially off the Changjiang River estuary. The impact of upwelling on hypoxia and, therefore, on the ecosystem in the ECS is not known. This study demonstrates both positive and negative effects of upwelling on hypoxia...

In contrast to other seagrass meadows where seawater carbonate chemistry generally shows strong diel variations with higher pH but lower partial pressure of CO2 (pCO2) during the daytime and lower pH but higher pCO2 during nighttime due to the alternation in photosynthesis and respiration, the seagrass meadows of the inner lagoon (IL) on Dongsha Is...

Satellite-based observations of primary production (PP) are broadly used to assess carbon fixation rate of phytoplankton in the global ocean with small spatiotemporal limitations. However, the remote sensing can only reach the ocean surface, the assumption of a PP vertically exponential decrease with increasing depth from the surface to the bottom...

To explore nitrogen (N) and phosphorus (P) imbalances in the atmosphere in East Asia, we set up an atmospheric sampling station at the southern end of the East China Sea. From April 2019 to March 2020, we collected atmospheric particulates and rainwater samples and performed chemical analyses of inorganic and organic N and P species in the samples....

In this study, we investigated the seawater carbonate chemistry in the Dongsha Atoll Lagoon (DAL) in summer 2015, summer 2016, and autumn 2016. According to the calculation of the total alkalinity anomaly (ΔTA), the DAL is currently maintaining a net calcification status, with higher calcification potential in summer and lower calcification potenti...

Since half a century ago, the number and area of dead zones (dissolved oxygen (DO) < 2 mg L–1 or 30% saturation) in the coastal oceans has increased dramatically. As widely recognized, the increased terrestrial nutrient and organic matter inputs are the two main factors causing the eutrophication of many coastal oceans. Here we show with decadal ob...

The short-term variabilities in temperature, salinity, nitrate, chlorophyll a (Chl a), and carbonate chemistry data (i.e., pH, partial pressure of CO2 (pCO2), total alkalinity, and dissolved inorganic carbon) were concurrently investigated in the shallow (∼50 m) and deep (∼300 m) water areas around Dongsha Atoll of the northern South China Sea (NSC...

Previous studies have found that calcification in coral reefs is generally stronger during the day, whereas dissolution is prevalent at night. On the basis of these contrasting patterns, the diel variations of net community calcification (NCC) were monitored to examine the relative sensitivity of CaCO3 production (calcification) and dissolution in...

Hypoxia (O2 ≤ 2 mg L-1) can severely threaten the survival of marine life and alter the biogeochemical cycles of coastal ecosystems. Its impacts are dependent on its duration. In the present study, hypoxia was observed in autumn at the end of October 2011. It may be one of the latest recorded annual hypoxic events in the East China Sea (ECS). In th...

The diurnal cycles of carbon chemistry parameters, i.e., dissolved inorganic carbon (DIC), total alkalinity (TA), partial pressure of CO2 (pCO2), and pH, were investigated in two hydrodynamically contrasting seagrass meadows at Dongsha Island in the northern South China Sea in August 2015. The results show that the pH and TA were higher and that th...

A central challenge in microbial ecology is to understand the underlying mechanisms driving community assembly, particularly in the continuum of species sorting and dispersal limitation. However, little is known about the relative importance of species sorting and dispersal limitation in shaping marine microbial communities; especially, how they ar...

Bioluminescent seas caused by blooms of the dinoflagellate Noctiluca scintillans are a famous scenic attraction in the Matsu archipelago near the Chinese coast in the northern part of the Taiwan Strait. The relationship between the abundance of N. scintillans and various environmental factors was examined in the subtropical coastal waters of these...

To understand the biogeochemical response to internal waves in the deep basin of the northern South China Sea (NSCS), particulate organic carbon (POC) export fluxes were quantified for the first time during the passage of large internal waves using drifting sediment traps attached with hydrographic sensors. Results revealed large variations in temp...

This study was designed to determine the effects of flooding on a pelagic ecosystem in the East China Sea (ECS) with a focus on plankton activity and plankton community respiration (CR). In July 2010, a flood occurred in the Changjiang River. As a comparison, a variety of abiotic and biotic parameters were monitored during this flooding event and d...

This study was designed to determine the effects of flooding on pelagic ecosystem in the East China Sea (ECS), especially on plankton community respiration (CR). In July 2010, a flood occurred in the Changjiang River. As a comparison, a variety of both abiotic and biotic parameters were monitored, as well as in July 2009, a non-flooding period. Dur...

To evaluate the effect of sample storage on pH analysis, a comparison experiment between field and laboratory pH measurements was conducted on a total of 88 seawater samples collected on the East China Sea shelf during 16 July 2014–29 July 2014. The results show that although pH directly measured onboard was statistically higher than the pH later m...

This study was designed to determine the effects of flooding on plankton community respiration (CR) in the East China Sea (ECS). In July 2010, a devastating flood occurred in the Changjiang River; the mean monthly discharge was 60 527 m3 s−1. To compare, the variables were also examined in the low riverine flow of July 2009 (33 955 m3 s−1). During...

The Hoping power plant (HPP), located on the northeastern coast of Taiwan, is considered an ideal site to test the accelerated weathering of limestone (AWL) technique for fossil fuel CO2 mitigation because the required reactants, seawater and limestone, are readily available and inexpensive to obtain. In this study, we investigated the current stat...

study effects of extreme weather events (EWEs, e.g., dust storm and typhoon) on the export of particulate organic carbon (POC) measured by a floating sediment trap in the oligotrophic ocean, eight sea-going expeditions were conducted in the oligotrophic northwest Pacific (NWP) in 2007 and 2008, covering all four seasons and the passage of several E...

Recent studies show that typhoons have profound effects on phytoplankton assemblages along their tracks, but it is difficult to quantitatively estimate nutrient supply after a typhoon's passage due to a lack of nutrient information before and after the arrival of a typhoon. During the passage of Typhoon Morakot (July 22 to Aug. 26, 2009), we conduc...

Author Posting. © Sears Foundation for Marine Research, 2013. This article is posted here by permission of Sears Foundation for Marine Research for personal use, not for redistribution. The definitive version was published in Journal of Marine Research 71 (2013): 451-452, doi:10.1357/002224013812587609.

Severe tropical storms play an important role in triggering phytoplankton blooms, yet direct field observation of evidence of the effects of a typhoon is very rare. Sea surface temperature (SST), nitrate concentration, chlorophyll a (chl a) concentration, and particulate organic carbon (POC) flux were measured before and shortly after Typhoon Jangm...

To assess the impact of rising atmospheric CO2 and eutrophication on the carbonate chemistry of the East China Sea shelf waters, saturation states (Ω) for two important biologically relevant carbonate minerals – calcite (Ωc) and aragonite (Ωa) – were calculated throughout the water column from dissolved inorganic carbon (DIC) and total alkalinity (...

A tremendous amount of organic carbon respired by plankton communities has been found in summer in the East China Sea (ECS), and this rate has been significantly correlated with fluvial discharge from the Changjiang River. However, respiration data has rarely been collected in other seasons. To evaluate and reveal the potential controlling mechanis...

To assess the impact of rising atmospheric CO2 and eutrophication on the carbonate chemistry of the East China Sea shelf waters, saturation states (Ω) for two important biologically-relevant carbonate minerals, calcite (Ωc) and aragonite (Ωa) were calculated throughout the water column from dissolved inorganic carbon (DIC) and total alkalinity (TA)...

Model studies suggested that human-induced increase in nutrient load may have stimulated primary production and thus has enhanced the CO2 uptake capacity in the coastal ocean. In this study, we investigated the seasonal variations of the surface water's partial pressure of CO2 (pCO2sw) in the highly human-impacted Changjiang-East China Sea system b...

A tremendous amount of organic carbon respired by plankton communities has been found in summer in the East China Sea (ECS), and this rate has been significantly correlated with fluvial discharge from the Changjiang River. However, respiration data has rarely been collected in other seasons. To evaluate and reveal the potential controlling mechanis...

Particulate nitrogen (PN) dynamics in the oligotrophic northern South China Sea (around the SouthEast Asian Time-series Study (SEATS) station) was explored by examining the isotopic compositions of suspended PN in the top 200 m over 3 years and sinking PN collected by sediment traps. The PN inventory (IPN) in the upper 100 m is larger than in the l...

To explore the effect of atmospheric forcing on the CO2 system in the subtropical northwest Pacific Ocean, which is oligotrophic and nitrogen limited, total alkalinity (TA), dissolved inorganic carbon (DIC), fugacity of CO2 (fCO2), and other pertinent data (i.e. temperature, salinity, and concentrations of nitrate and chlorophyll a (Chl a)) were co...

The time-series station, SEATS (18 degrees N, 116 degrees E) in the South China Sea was visited six times during October 2006-December 2008 to carry out seawater sampling and floating trap deployments for the determination of distributions and fluxes of POC, PIC, PN, Th-234, Pb-210, and Po-210 in the upper 200m of the water column. Radionuclide def...

Human inputs of nutrients to coastal waters can lead to the excessive production of algae, a process known as eutrophication. Microbial consumption of this organic matter lowers oxygen levels in the water. In addition, the carbon dioxide produced during microbial respiration increases acidity. The dissolution of atmospheric carbon dioxide in ocean...

The time-series station, SEATS (18° N, 116° E) in the South China Sea was visited six times during October 2006-December 2008 to carry out seawater sampling and floating trap deployments for the determination of distributions and fluxes of POC, PIC, PN, 234Th, 210Pb, and 210Po in the upper 200 m of the water column. Radionuclide deficiencies result...

The diurnal to weekly dynamics of carbon and oxygen in two productive tropical-subtropical nearshore shallow water systems were investigated using a combination of time-series observation and modeling. The two sites, Aodi (121.93 degrees E, 25.06 degrees N) and Nanwan (120.85 degrees E, 21.91 degrees N), were characterized by limited freshwater inp...

The occurrence of extreme weather conditions appears on the rise under current climate change conditions, resulting in more frequent and severe floods. The devastating floods in southern China in 2010 and eastern Australia 2010-2011, serve as a solemn testimony to that notion. Accompanying the excess runoffs, elevated amount of terrigenous material...

Moored sediment traps were deployed for 1 yr at depths of 120, 600, and 3500 m in the water column to investigate the trace metal (M) (Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn) composition, sources, and fluxes of deep-water sinking particles. Vertical transport for most of the metals at 120 m was strongly associated with organic matter production,...

This study reports on the stable isotopic composition of modern planktonic foraminifera tests collected from plankton tows and sediment trap moorings in the northern South China Sea. Plankton tow samplings were conducted at water depths of 50, 100, and 200m during various seasons between December 2002 and August 2008. The sediment trap array was de...

Measurements of dissolved inorganic carbon (DIC), pH, total alkalinity (TA), and partial pressure of CO2 (pCO2) were conducted at a total of 25 stations along four cross shelf transects in the East China Sea (ECS) in January 2008. Results showed that their distributions in the surface water corresponded well to the general circulation pattern in th...

The nutrient loads exported from the Changjiang River into the East China Sea (ECS) has increased over 10-fold since the 1960s because of anthropogenic disturbance such as intensive use of chemical fertilizers and the discharge of industrial and municipal waste waters. Elevated nutrient discharge causes eutrophication of the coastal waters, and sti...

This study reports the first high and low molecular weight measurements of dissolved organic nitrogen (DON) in size-fractionated atmospheric particles. The variations in concentration of nitrogen species corresponded to varying sources and weather conditions. The results indicate that continental, local, and marine origins are the key factors contr...

The eastern equatorial Pacific is the predominant source area for atmospheric CO2, and the size of this source is significantly reduced during El Niño events. Here we apply a newly constructed 1999–2008 time series carbon chemistry trend to show a similar reduction can also be identified in the northern South China Sea. The net sea-to-air CO2 flux...

Severe tropical storms play an important role in triggering phytoplankton blooms, but the extent to which such storms influence carbon flux from the euphotic zone is unclear. In 2008, typhoon Fengwong provided a unique opportunity to study the in situ biological responses including phytoplankton blooms and particulate organic carbon fluxes associat...

Severe tropical storms play an important role in triggering phytoplankton blooms, but the extent to which such storms influence biogenic carbon flux from the euphotic zone is unclear. In 2008, typhoon Fengwong provided a unique opportunity to study the in situ biological responses including phytoplankton blooms and particulate organic carbon fluxes...

We deployed floating traps in the surface waters of the South China Sea on four occasions at depths of 30 m, 100 m, and 160 m from 2006 to 2007 to quantify vertical metal fluxes in the surface water and examine trace metal composition in the sinking particles to investigate their sources. The elements determined include 13 trace metals and 8 major...

Concentrations of dissolved (234 Th d) and particulate (234 Th p) 234 Th in surface water at 38 stations in the Taiwan Strait were determined for samples collected in May 2006. The spatial distribution of 234 Th in the Taiwan Strait is controlled by advec-tive input of Kuroshio Branch Water via the Peng-Hu Channel and fast removal due to the high i...

The South China Sea (SCS) exhibits strong variations on seasonal to interannual time scale, and the changing Southeast Asian Monsoon has direct impacts on the nutrients and phytoplankton dynamics, as well as the carbon cycle. A Pacific basin-wide physi-cal-biogeochemical model has been developed and used to investigate the physical variations, ecos...

1] To explore the paradox that the heterotrophic waters of the East China Sea (ECS) shelf act as a significant CO 2 sink in summer, vertical structures of carbon chemistry and hydrography were examined in July 2007. The results show that waters above the pycnocline ($10 to 30 m) in the major CO 2 sink area are supersaturated with oxygen (110 ± 7%;...

Comprehensive carbon chemistry data including total alkalinity (TA), dissolved inorganic carbon (DIC), pH, fugacity of CO2, and other pertinent data (i.e., temperature, salinity, and levels of nitrate and chlorophyll a) were measured in surface waters of the East China Sea (ECS) shelf in July 2007. The results show that spatial variations in these...

The concentrations of cadmium, phosphorus, and aluminum in size-fractionated phytoplankton, zooplankton, and sinking particles are determined using ICPMS to evaluate the roles of biotic and abiotic particles on the cycling and ratios of Cd and P in the water column. Plankton were collected with a filtration apparatus equipped with 10-, 60-, and 150...

Export of dissolved inorganic carbon (DIC) to adjoining oceans enhances the potential of CO2 sequestration in marginal seas. By using a series of measured DIC depth profiles and reported flow transports, we estimated that the intermediate outflow (100-600 m) from the South China Sea is capable of transporting 6.5 ± 4.1 Tg (1 Tg = 1012g) of biologic...

Depth distributions of pH, dissolved oxygen, dissolved inorganic carbon (DIC), total alkalinity (TA), and delta 13CDIC in the water column across the Luzon Strait from the South China Sea to the west Philippine Sea were investigated thoroughly to attest whether the South China Sea subsurface water outflow could act like a ``shelf pump'' to export t...

The distributions of total carbon dioxide (TCO2) and alkalinity (TA) in the upper layer at the SouthEast Asian Time-series Study (SEATS) station at 18°N, and 116°E in the northern South China Sea (SCS) were determined on 19 cruises between September 1999 and October 2003. The variations in the concentrations of TCO2 and TA in the mixed layer, which...

Between May 2004 and March 2005, samples of suspended particulate matter (SPM) were collected from the top 200m on five cruises to the South-East Asia time-series study (SEATS) Station. Isotopic and elemental analyses of the organic matter in these samples gave δ13C values ranging from −25.2‰ to −21.3‰ with a decreasing trend downward, and C/N rati...

In this study, measurements of titration alkalinity (TA), total dissolved carbon dioxide (TCO2), and δ¹³C of TCO2 ( ) throughout the water column at the SouthEast Asian time-series study (SEATS) site were investigated in order to understand better the fundamental processes controlling their vertical distributions in the South China Sea (SCS). The l...

The continuous summertime drawdown of normalized dissolved inorganic carbon has been observed repeatedly in the mixed-layer at the South East Asia Time-series Study (SEATS) site, northern South China Sea (SCS) between March 2002 and November 2004. Mass balance calculation reveals that a net community production (NCP) of -4.47 mmolC m-2 day-1 is res...