Promoting effect of raft-raised scallop culture on the formation of coastal hypoxia.

The coastal waters around the Yangma Island are an important mariculture area of raft-raised scallop and bottom-seeded sea cucumber in the North Yellow Sea, China. Large-scale hypoxia in the bottom water of this area has caused the death of a large number of sea cucumbers and heavy economic losses. To find out the formation mechanism of hypoxia, the data obtained in each August during 2015-2018 were analyzed.

The joint effects of atmospheric dry and wet deposition on organic carbon cycling in a mariculture area in North China.

In this research, the atmospheric dry and wet deposition fluxes of particulate organic carbon (POC) over the coastal waters around the Yangma Island in North Yellow Sea were investigated. Combining the results of this research and previous reports about the wet deposition fluxes of dissolved organic carbon (DOC) in precipitation (F) and dry deposition fluxes of water-dissolvable organic carbon in atmospheric total suspended particles (F) in this area, a synthetic assessment of the influence of atmospheric deposition on the eco-environment was conducted. It was found that the annual dry deposition flux of POC was 1097.

Atmospheric deposition as a direct source of particulate organic carbon in region coastal surface seawater: Evidence from stable carbon and nitrogen isotope analysis.

To assess the source characteristics of coastal aerosols and evaluate the contribution of atmospheric deposition to particulate organic matter in surface seawater, total suspended particulates (TSP) were collected at a shore-based site on the south coast of North Yellow Sea from December 2019 through November 2020. The samples were analyzed for total organic carbon (TOC) and nitrogen (TN) as well as stable carbon and nitrogen isotope (δC and δN). The results showed that the annual mean concentrations of TOC and TN were 5.

Atmospheric wet deposition serves as an important nutrient supply for coastal ecosystems and fishery resources: Insights from a mariculture area in North China.

To determine the ecological effects of atmospheric wet deposition of dissolved nutrients on the coastal waters around the Yangma Island, rain and snow samples were collected and analyzed at a shore-based site for one year. The wet deposition fluxes of dissolved inorganic nitrogen and phosphorus (DIN and DIP) and dissolved organic nitrogen and phosphorus were 69.2, 0.

Biogeochemical properties and fate of dissolved organic matter in wet deposition: Insights from a mariculture area in North Yellow Sea.

To address the potential roles of atmospheric wet deposition in carbon cycling in coastal waters, a comprehensive study of the biogeochemical properties of dissolved organic matter (DOM) in precipitation and the resulting implication in a mariculture area in North Yellow Sea was conducted. The annual mean concentrations of dissolved organic carbon (DOC), chromophoric and fluorescent dissolved organic matter (CDOM and FDOM) were 1.52 ± 1.

Atmospheric dry deposition of water-soluble organic matter: An underestimated carbon source to the coastal waters in North China.

Water-soluble organic matter (WSOM) is a ubiquitous group of organic compounds in the atmosphere, which plays an important role in the biogeochemical cycle. To determine the quantity and chemical composition of the dry deposition of WSOM and assess its ecological effects on the coastal waters around the Yangma Island, North Yellow Sea, total suspended particulates (TSP) samples collected at a coastal site for one year from December 2019 to November 2020 were analyzed. The concentration of water-soluble organic carbon (WSOC) and the spectroscopy of chromophoric dissolvable organic matter (CDOM) and fluorescent dissolvable organic matter (FDOM) in the samples showed highly temporal variability with higher values in winter and spring than in summer and autumn.

Summer deoxygenation in a bay scallop (Argopecten irradians) farming area: The decisive role of water temperature, stratification and beyond.

During 2015-2020, 26 cruises were carried out in a bay scallop farming area, North Yellow Sea, to study the dissolved oxygen (DO) dynamics and its controlling factors. Significant DO depletion (deoxygenation) was observed in the summertime with the decrease rates of 0.31-0.

The impacts of intensive scallop farming on dissolved organic matter in the coastal waters adjacent to the Yangma Island, North Yellow Sea.

In-situ field investigations coupled with incubation experiments were conducted in the coastal waters adjacent to the Yangma Island to explore the impacts of intensive bay scallop farming on the quantity and composition of dissolved organic matter (DOM). During the scallop farming period, the values of dissolved organic carbon (DOC), chromophoric dissolved organic matter (CDOM) and fluorescence dissolved organic matter (FDOM) in the mariculture area (MA) were generally higher than those in the non-mariculture area (NMA). Bay scallops released a large amount of DOM with the characteristics of high molecular weight and low degree of humification into the water column through excretion, which altered the DOM biogeochemical cycle.

Perpetual atmospheric dry deposition exacerbates the unbalance of dissolved inorganic nitrogen and phosphorus in coastal waters: A case study on a mariculture site in North China.

The monthly magnitudes of dissolvable nutrients through atmospheric dry deposition (ADD) and their ecological effects to the coastal waters around the Yangma Island, North Yellow Sea, were investigated for one year. The results indicated that anthropogenic activities were the major sources of dissolvable inorganic and organic nitrogen (DIN and DON); dust events were the major sources of inorganic phosphorus (DIP) and silicate (DSi); however, organic phosphorus (DOP) could be originated from marine biological activities. The annual ADD fluxes of DIN, DON, DIP, DOP and DSi were 21.

Massive shellfish farming might accelerate coastal acidification: A case study on carbonate system dynamics in a bay scallop (Argopecten irradians) farming area, North Yellow Sea.

Seven cruises were carried out in a bay scallop (Argopecten irradians) farming area and its surrounding waters, North Yellow Sea, from March to November 2017 to study the dynamics of the carbonate system and its controlling factors. Results indicated that the studied parameters were highly variability over a range of spatiotemporal scales, comprehensively forced by various physical and biological processes. Mixing effect and scallop calcification played the most important role in the seasonal variation of total alkalinity (TAlk).

Utilizing benthic foraminifera to explore the environmental condition of the Laizhou Bay (Bohai Sea, China).

Through the analysis of benthic foraminifera in the soft bottom sediments of the Laizhou Bay - Yellow River Delta system, this study characterized the foraminiferal biotopes and explored the possibility of obtaining an index of ecological quality comparable with other estuarine and coastal environments of the world. Five foraminiferal biotopes have been identified and their distribution patterns highlight the ecological stress from the marine-fluvial water mixing and pollution. The foraminiferal species were analyzed as a function of organic carbon gradients, and the main species were assigned to four ecological groups based on their sensitivity/tolerance towards an increasing stress gradient.

Potential linkage between sedimentary oxygen consumption and benthic flux of biogenic elements in a coastal scallop farming area, North Yellow Sea.

Surface sediments were collected from a mariculture area adjacent to the Yangma Island suffering from hypoxia in summer, and a laboratory static incubation was conducted to study the sedimentary oxygen consumption (SOC) and the benthic fluxes of nutrients and fluorescent dissolved organic matter (FDOM). Compared with some coastal areas, the SOC of the studied area was relatively low in summer with the value of 2.34-6.

The influence of summer hypoxia on sedimentary phosphorus biogeochemistry in a coastal scallop farming area, North Yellow Sea.

In situ field investigations coupled with laboratory incubations were employed to explore the surface sedimentary phosphorus (P) cycle in a mariculture area adjacent to the Yangma Island suffering from summer hypoxia in the North Yellow Sea. Five forms of P were fractionated, namely exchangeable P (Ex-P), iron-bound P (FeP), authigenic apatite (CaP), detrital P (De-P) and organic P (OP). Total P (TP) varied from 13.

Effects of Inulin Propionate Ester on Obesity-Related Metabolic Syndrome and Intestinal Microbial Homeostasis in Diet-Induced Obese Mice.

Short-chain fatty acid (SCFA) plays an important role in improving obesity and related metabolic syndrome induced by high-fat diet. We used the prepared inulin propionate ester (IPE) as a system for the targeted release of propionate to the colon to elucidate the role of IPE in regulating obesity and metabolic syndrome, and intestinal microbial homeostasis, in diet-induced obese mice. With this strategy, IPE significantly increased the SCFA contents in the colon and resulted in significant body weight reduction, insulin resistance amelioration, and gastrointestinal hormone (glucagon-like peptide and peptide YY) secretion ( < 0.

Sediment quality of the Bohai Sea and the northern Yellow Sea indicated by the results of acid-volatile sulfide and simultaneously extracted metals determinations.

The surface sediments from the Bohai Sea (BS) and the northern Yellow Sea (NYS) were analyzed for acid-volatile sulfide (AVS) and simultaneously extracted metals (SEM) to assess the sediment quality. The results indicated that >60% of the samples were found to have possible adverse effects on aquatic life in the BS based on the difference between the concentrations of AVS ([AVS]) and SEM ([SEM]), and the corresponding percentage in the NYS was <25%. Nevertheless, there was no indication of adverse effects for all the BS and the NYS samples when the total organic carbon (TOC) concentration was introduced in the sediment quality evaluation with [AVS] and [SEM].

Colloidal toxic trace metals in urban riverine and estuarine waters of Yantai City, southern coast of North Yellow Sea.

The environmental characteristics of colloidal toxic trace metals Cd, Cu and Pb in riverine and estuarine waters collected from two urban rivers of Yantai City in eastern China, the Guangdang and Xin'an Rivers, were investigated using a modified centrifugal ultrafiltration (CUF) method in conjunction with acid extraction and inductively coupled plasma mass spectrometry. The target metals in dissolved pool were divided into four CUF fractions, i.e.

Biogeochemistry of dissolved inorganic nutrients in an oligotrophic coastal mariculture region of the northern Shandong Peninsula, north Yellow Sea.

Fourteen field cruises were carried out in a mariculture region of the northern Shandong Peninsula, North Yellow Sea, China from 2016 to 2017 for a better understanding of the biogeochemical behaviors, sources and export of dissolved inorganic nutrients. The spatial variations of nutrients were not obvious due to the influence of complex hydrological and biochemical conditions. Potential nutritional level was characterized in oligotrophy, and trophic status was rated at medium level.

Adsorption and fractionation of Pt, Pd and Rh onto inorganic microparticles and the effects of macromolecular organic compounds in seawater.

Adsorption and fractionation of Pt, Pd and Rh (defined here as platinum group elements, PGEs) onto the representative inorganic microparticles, including FeO, MnO, CaCO, SiO, AlO and kaolinite in seawater were investigated. The effects of macromolecular organic compounds (MOCs) as the representatives of organic matter, including humic acids (HA), bovine serum albumin (BSA) and carrageenan, on the adsorption were also studied considering that organic matter is ubiquitous in seawater and indispensable to marine biogeochemical cycles. In the absence of MOCs, the representative mineral particles FeO and MnO had the strongest interaction with PGEs.

Determination of ultra-trace Pt, Pd and Rh in seawater using an off-line pre-concentration method and inductively coupled plasma mass spectrometry.

A method was modified for the preconcentration of platinum (Pt), palladium (Pd) and rhodium (Rh) from seawater by a solid phase extraction using a commercially available resin Nobias-chelate PA1. All the determination was conducted using inductively coupled plasma mass spectrometry (ICP-MS) which had a low detection limit for Pt, Pd and Rh, about 16.53, 16.

Submarine Groundwater Discharge helps making nearshore waters heterotrophic.

Submarine groundwater discharge (SGD) is the submarine seepage of all fluids from coastal sediments into the overlying coastal seas. It has been well documented that the SGD may contribute a great deal of allochthonous nutrients to the coastlines. It is, however, less known how much carbon enters the ocean via the SGD.

The distribution and seasonal variations of sedimentary organic matter in the East China Sea shelf.

We sampled the surface sediments of the East China Sea shelf (ECSS) in spring and autumn, 2014, and analyzed the biogenic element concentrations and stable carbon (δC) and nitrogen (δN) isotopic compositions to study the distribution and seasonal variations of sedimentary organic matter (OM). The average concentrations of TOC, TN and OP in autumn decreased obviously compared with those in spring. The increase of δN values in autumn indicated the priority utilization of N by bacterial decomposition activity.

Comprehensive large-scale investigation and assessment of trace metal in the coastal sediments of Bohai Sea.

The Bohai Sea is characterized as a semi-closed sea with limited water exchange ability, which has been regarded as one of the most contaminated regions in China and has attracted public attention over the past decades. In recent years, the rapid industrialization and urbanization around the coastal region has resulted in a severe pollution pressure in the Bohai Sea. Although efforts from official government and scientific experts have been made to protect and restore the marine ecosystem, satisfactory achievements were not gained.

Potential mobility of inorganic nutrients and its controls at the sediment-water interface in the main path of Kuroshio Current off eastern Taiwan.

Surface sediments were collected from the main path of Kuroshio Current (KC) off eastern Taiwan (ETW), and laboratory incubation was conducted for the study of the nutrient exchange at the sediment-water interface. Exchange fluxes of NO-N, NO-N, NH-N, PO-P and SiO-Si under simulated site condition were -0.0866, 0.