Chinese Coastal Areas Research Articles

Implications of Local Sources to Probabilistic Tsunami Hazard Analysis in South Chinese Coastal Area

The South China Sea is recognized as an area at high risk of tsunamis. The Manila Trench has long been considered as the regional source of tsunamis that might affect Chinese coastal areas, and considerable analysis of the tsunami hazard has been conducted in this area. However, there has been no consideration of other potential local sources near the coastal area. Thus, the locations of local potential tsunami sources (PTSs) along the southern coast of China and the evaluation of their impact on tsunami hazard assessment require investigation. We identified eight local PTSs for given seismic activity parameters. For the probabilistic tsunami hazard analysis (PTHA), the lower-limit earthquake magnitude was determined as 7.0, based on numerical simulation of tsunami scenarios. Six measured sites in the Pearl River Estuary and Taiwan Strait were selected for PTHA, which were referenced to Macao, Hong Kong, Daya Bay, Shantou, Xiamen, and Quanzhou. The annual rate of tsunami waves exceeding a given height [Formula: see text] was calculated for each site. The results show that the upper-limit earthquake magnitude and the relative geographical positions of the measured site of interest and the PTS are two of the most important factors in the PTHA computation. The probabilities of tsunami waves exceeding a given height [Formula: see text] within 100 years and their return periods were calculated for each site. The results show that the probability of [Formula: see text][Formula: see text]m within 100 years is 30–40% in Xiamen and Quanzhou but 5–10% in Macao and Hong Kong. If the Manila Trench were considered as a regional source, these probabilities would be higher. It is concluded that the tsunami hazard on the southern coast of China is very high and that both regional and local PTSs should be included in any future PTHA.

Land-ocean-human interactions in intensively developing coastal zone: Demonstration of case studies

Land-Ocean-Human (L-O-H) interactions in intensively developing coastal zones are demonstrated using four case studies in the western Bohai Sea, China. Three aspects of L-O-H interactions are discussed: 1. Coastlines are the result of Land-Ocean (L-O) interactions, but human activities have changed many coastlines from natural to artificial. In recent years, sea reclamation projects have moved the land and its coastline towards the sea, leading to hydrodynamic changes and affecting both the topography and sediment-erosion dynamics in western Bohai Bay (case study 1). 2. Estuaries are key areas for L-O interactions; river sediments, together with ocean power, shape the topography of the estuarine delta, while river nutrients impact offshore biological productivity. However, due to irrigation and reservoir construction up-stream, runoff and sediments have decreased resulting in increased coastal erosion in the Yellow River Delta (case study 2). Rivers carry industrial and agricultural point and non-point source pollution into the sea, causing marine pollution in Jinzhou Bay (case study 3). 4. Sea-level rise caused by global climate change enhances the role of the ocean. At a local scale, in Binhai New Area, sea-level change is also influenced by vertical land movement along with some land subsidence caused by over-exploitation of groundwater. Rising sea levels exacerbate storm surges and floods, and increase the risk of socio-economic and ecological impacts (case study 4). Because of rapid economic growth in Chinese coastal areas, L-O-H interactions have become the most significant factors changing natural and artificial environments. If the coastal zone is to be developed sustainably, human activities must be regulated.

Chinese Marine Materia Medica Resources: Status and Potential.

Chinese marine materia medica (CMMM) is a vital part of traditional Chinese medicine (TCM). Compared with terrestrial TCM, CMMM, derived from specific marine habitats, possesses peculiar chemical components with unique structures reflecting as potent pharmacological activities, distinct drug properties and functions. Nowadays, CMMM appears to be especially effective in treating such difficult diseases as cancers, diabetes, cardio-cerebrovascular diseases, immunodeficiency diseases and senile dementia, and therefore has become an important medicinal resource for the research and development of new drugs. In recent years, such development has attracted wide attention in the field of medicine. In this study, the CMMM resources in China were systematically investigated and evaluated. It was found that the historic experiences of Chinese people using CMMM have continuously accumulated over a period of more than 3600 years, and that the achievements of the research on modern CMMM are especially outstanding. By June 2015, 725 kinds of CMMMs from Chinese coastal sea areas have been identified and recorded, covering 1552 organisms and minerals. More than 3100 traditional prescriptions containing CMMMs have been imparted and inherited. However, the number of CMMMs is less than the 8188 terrestrial TCMs, from more than 12,100 medicinal terrestrial plants, animals and minerals. In the future, the research and development of CMMM should focus on the channel entries (TCM drug properties), compatibility, effective ingredients, acting mechanisms, drug metabolism and quality standard. This study reveals the high potential of CMMM development.

Study of Reciprocal Effects between Mandatory Pollutant Emissions Reduction Policy and Structural Change within the Manufacturing Sector in a Chinese Coastal Area.

We develop a multicriteria decision-making model coupled with scenario analysis to quantitatively elucidate the reciprocal effect between a mandatory pollutant emissions reduction policy and industrial structure change within the manufacturing sector on the basis of an in-depth study of a well-developed coastal area in East China, Ningbo City, toward 2020. First, 18 two-digit level industries (TDLIs) in the manufacturing sector are screened out due to intensive emissions of the four pollutants (COD, NH3-N, SO2, and NOx). Second, a model is established to identify the optimal solution for the industrial structure adjustment of the 18 TDLIs under two scenarios, the "business-as-usual" scenario and the "industrial structure adjustment" scenario. Both scenarios are expanded into three subscenarios. Quantitative constraint conditions and two criteria are formulated to screen out the optimal solutions. We propose a coefficient of industrial structure adjustment, Ki, which could clearly reflect the policy preference in terms of industrial development and reallocate the quota of the four-pollutant emission among the 18 TDLIs with regards to the different expectations of economy development in 2020. The model will help local authorities make tailored policies to reduce pollution emissions effectively through industrial structure change by delicately allocating the pollutant emission quota and setting reasonable targets of emission intensity reduction among TDLIs.

Detection and calibration of anthropogenic lead emission in coastal sediments of China during the past 250 years.

The historical fluctuation of lead (Pb) content in coastal sediments of China and its link with human activities have been extensively studied. However, the determined Pb profiles from even the same regions could contradict each other, likely due to the fact that different methods are used in detecting anthropogenic Pb emission. In the present study, we analyzed grain size distribution and Pb levels in three sediment cores from Chinese coastal areas, and observed a significant enrichment of Pb in the sediment fraction of fine grain size. Based upon this observation, we normalized the Pb concentrations during the past 250 years by fine grain size content. The normalized Pb profiles showed consistent, increasing trends in the three cores and a remarkable rise after the Industrial Revolution. The regional characteristics in the normalized Pb profiles of Chinese offshore sediments are consistent with those of terrestrial sediments. This new normalization method is robust and cost-effective for studying anthropogenic Pb emissions in coastal sediments.

Relationship between vitmin D receptor rs2228570 polymorphism and susceptibility to gout in Chinese Han male population

Objective To explore gene polymorphism of G/A genotype of FokⅠrs2228570(G/A)of vitamin D receptor(VDR)gene in Han male population of Chinese coastal area, and thus to investigate the relationship between the gene polymorphism of VDR and gout. Methods Altogether 504 gout patients and 523 healthy controls were enrolled. The possible association between the polymorphism of VDR rs2228570 and gout in Chinese coastal area was investigated and genotype frequencies and allelic frequencies were calculated by realtime PCR with Taqman® probe method. Hardy-Weinberg was used to verify the representativeness of the sample. Comparison between the groups were performed with χ2 test and t-test. Results The frequencies of GG, AG, and AA genotypes were 32.1%, 50.0%, and 17.9%, respectively among gout patients, while they were 27.9%, 50.5%, and 21.6% respectively among the controls. There was no statistically significant difference in VDR rs2228570 genotype frequencies between gout patients and controls(χ2=3.366, P>0.05). The allele frequencies of G and A in gout cases were different from those in the controls(57.1%, 42.9%; 53.2%, 46.8%; χ2=3.300, P>0.05). Conclusions Results of the present study suggest that the G/A genotype of VDR FokⅠrs2228570 of the VDR gene is not associated with gout in male population of Chinese coastal area. (Chin J Endocrinol Metab, 2015, 31: 316-319) Key words: Vitmin D receptor; Polymorphism, single Nucleotide; Gout

A Study of the Effect of Country Image on Foreign Products’ Customer Satisfaction and Repurchase Intention: A Comparative Study between Korean and French Cosmetics Product in Chinese Coastal Area

A Study of the Effect of Country Image on Foreign Products’ Customer Satisfaction and Repurchase Intention: A Comparative Study between Korean and French Cosmetics Product in Chinese Coastal Area

Use of isotopic compositions of nitrate in TSP to identify sources and chemistry in South China Sea

NO3− concentration, nitrogen and oxygen isotopic compositions (δ15N and δ18O) of NO3− were measured in total suspended particulates (TSP) at Yongxing Island in the South China Sea (SCS) between Feb. 2013 and Jan. 2014, as well as on two cruises in the northern South China Sea (NSCS). Measurements aimed to identify NO3− sources, and possible chemical formation processes of NO3−. The δ15N and δ18O of NO3− in TSP at Yongxing Island ranged from −2.5 to +4.9‰, and +48.1 to +99.0‰, with annual weighted averages of +1.5‰ and +83.2‰, respectively. Both δ15N and δ18O had higher values in cool months, indicating that NOx sources and oxidants were different between seasons. In cool months, NOx was mainly from anthropogenic sources, particularly from coal combustion in South China, resulting in high nitrogen deposition that was oxidized by O3 to NO3−. In warm months, natural emissions were an important source of NOx. TSP samples in the NSCS had higher NO3− concentrations, higher δ15N and lower δ18O values than samples from Yongxing Island over the same period. This suggests that atmospheric processes caused a decrease in NO3− concentrations and δ15N but increase in δ18O from coast to remote marine. Assuming to oxygen atoms were derived from O3 during transport in cool months, the mean ratio of NO3− formed by NOx to total NO3− was calculated to be 47.9%. This suggests the mean loss ratio of NOx was 89% while the loss ratio of NO3− was 87% during transport between Chinese coastal areas and Yongxing Island in Nov., 2013.

Exotic Spartina alterniflora invasion alters ecosystem-atmosphere exchange of CH4 and N2O and carbon sequestration in a coastal salt marsh in China.

Coastal salt marshes are sensitive to global climate change and may play an important role in mitigating global warming. To evaluate the impacts of Spartina alterniflora invasion on global warming potential (GWP) in Chinese coastal areas, we measured CH4 and N2O fluxes and soil organic carbon sequestration rates along a transect of coastal wetlands in Jiangsu province, China, including open water; bare tidal flat; and invasive S. alterniflora, native Suaeda salsa, and Phragmites australis marshes. Annual CH4 emissions were estimated as 2.81, 4.16, 4.88, 10.79, and 16.98 kg CH4 ha(-1) for open water, bare tidal flat, and P. australis, S. salsa, and S. alterniflora marshes, respectively, indicating that S. alterniflora invasion increased CH4 emissions by 57-505%. In contrast, negative N2O fluxes were found to be significantly and negatively correlated (P < 0.001) with net ecosystem CO2 exchange during the growing season in S. alterniflora and P. australis marshes. Annual N2O emissions were 0.24, 0.38, and 0.56 kg N2O ha(-1) in open water, bare tidal flat and S. salsa marsh, respectively, compared with -0.51 kg N2O ha(-1) for S. alterniflora marsh and -0.25 kg N2O ha(-1) for P. australis marsh. The carbon sequestration rate of S. alterniflora marsh amounted to 3.16 Mg C ha(-1) yr(-1) in the top 100 cm soil profile, a value that was 2.63- to 8.78-fold higher than in native plant marshes. The estimated GWP was 1.78, -0.60, -4.09, and -1.14 Mg CO2 eq ha(-1) yr(-1) in open water, bare tidal flat, P. australis marsh and S. salsa marsh, respectively, but dropped to -11.30 Mg CO2 eq ha(-1) yr(-1) in S. alterniflora marsh. Our results indicate that although S. alterniflora invasion stimulates CH4 emissions, it can efficiently mitigate increases in atmospheric CO2 and N2O along the coast of China.

中国沿海地域が日本経済に及ぼした影響

中国沿海地域が日本経済に及ぼした影響

Chinese coastal seas are facing heavy atmospheric nitrogen deposition

As the amount of reactive nitrogen (N) generated and emitted increases the amount of N deposition and its contribution to eutrophication or harmful algal blooms in the coastal zones are becoming issues of environmental concern. To quantify N deposition in coastal seas of China we selected six typical coastal sites from North to South in 2011. Concentrations of NH3, HNO3, NO2, particulate NH4+ (pNH4+) and pNO3− ranged from 1.97– 4.88, 0.46 –1.22, 3.03 –7.09, 2.24 – 4.90 and 1.13–2.63 μg N m−3 at Dalian (DL), Changdao (CD), Linshandao (LS), Fenghua (FH), Fuzhou (FZ), and Zhanjiang (ZJ) sites, respectively. Volume-weighted NO3−–N and NH4+–N concentrations in precipitation varied from 0.46 to 1.67 and 0.47 to 1.31 mg N L−1 at the six sites. Dry, wet and total deposition rates of N were 7.8–23.1, 14.2–25.2 and 22.0 – 44.6 kg N ha−1 yr−1 across the six coastal sites. Average N dry deposition accounted for 45.4% of the total deposition and NH3 and pNH4+ contributed to 76.6% of the dry deposition. If we extrapolate our total N deposition of 33.9 kg N ha−1 yr−1 to the whole Chinese coastal sea area (0.40 million km2), total N deposition amounts to 1.36 Tg N yr−1, a large external N input to surrounding marine ecosystems.

Ion chemistry for atmospheric size-segregated aerosol and depositions at an offshore site of Yangtze River Delta region, China

An intensive sampling campaign was conducted in the autumn of 2012 to study the size distribution of inorganic ions and ion deposition at an offshore site of Yangtze River Delta region (YRD), China. Particles in <0.43, 0.43–0.65, 0.65–1.1, 1.1–2.1, 2.1–3.3, 3.3–4.7, 4.7–5.8, 5.8–9.0 and 9.0–10.0μm were collected and analyzed by ion chromatography for NH4+, Na+, Mg2+, K+, Ca2+, F−, Cl−, NO3− and SO42−. The average mass concentrations in the nine particle sizes ranged from 13.1 to 38.7μgm−3, accounting for 5.5%–16.8% of the total mass. Concentrations exhibit bi-modal distribution, peaking at 0.65–1.1μm and 3.3–4.7μm. PM1.1, PM2.1 and PM2.1–10 account for 41%, 56% and 44% of PM10 implying the dominance of finer particles. Different ions hold different size distribution patterns. The concentrations of NO3−, SO42−, NH4+, K+ and Ca2+ exhibit the highest values when compared to literature values indicating the serious air pollution situation in YRD. A haze–precipitation–fog transition course is captured. The precipitation can decrease all the particles in the nine sizes by 20%–62% and the fog formation process can promote the particles' accumulation, with their mass concentrations increasing by 26%–232% except for those in 5.8–9.0μm and 9.0–10μm. Mass percentages of SO42−, NO3− and NH4+ exhibit decreases during precipitation and increases during fog formation course. The anion to cation ratios are lower than 1.0 indicating the anion deficiency and they exhibit significant negative relationship with the particle diameter. The Cl-dep (%) is higher for particles larger than 0.65μm, increasing from 1.3% to 61% with size added. Sea salt only accounts for 0.12%–2.1% of PM10. The ratios of nss-SO42−/NO3− decrease with increasing particle size, from 1.68 to 0.69, and are well fit as linear form (r=−0.74, p=0.02). It indicates that stationary sources make more contributions to smaller particles and vehicle emission is more important for larger particles. The dry deposition fluxes for F−, Cl−, NO3− and SO42− are 3.10, 0.59, 22.99 and 17.04mg/(m2d). They exhibit multi-linear correlation with corresponding ion concentrations and the coefficients are higher for coarse particles. More researches are needed to obtain the distribution, transportation and deposition characteristic of ions at Chinese coastal area.

Seawater desalination in China: Retrospect and prospect

China has been and will be facing water shortage issues due to the disparity between water supply and demand, especially within Chinese coastal areas. Seawater desalination can increase the total water supply and is an important component in addressing water shortage issues in China. With the development of the last six decades, seawater desalination technologies and applications have been advanced remarkably. Total seawater desalination capacity has increased from 10,000m3/d in 2000 to approximately 660,000m3/d in 2011. Seawater desalination has been primarily used in power generation, steel manufacturing, petrochemical industry, and public water supply. 75 desalination plants have been constructed in China, among which 16 desalination plants have capacities of 10,000m3/d or more. Nine desalination plants are under construction, which will provide capacity of 408,000m3/d. Most of the desalination applications (99.5% of the desalination capacity) are located within five provinces: Liaoning, Shandong, Hebei, Tianjin, and Zhejiang. The dominant desalination technologies are reverse osmosis (RO) and multi-effect distillation (MED). 80.3% of desalination plants employ RO and 14.5% of desalination plants adopt MED. The desalination capacities of RO and MED are 348,000 and 232,000m3/d, respectively. Facing the challenge of water shortage, seawater desalination is of necessity in China and is increasingly an inevitable national strategy to address the issue. China is one of the most promising market for seawater desalination. However, international desalination companies will still dominate seawater desalination market for the foreseeable future.

Development of polymorphic microsatellite markers and the population genetic structure of the half-fin anchovy, Setipinna taty.

Microsatellite markers for the half-fin anchovy Setipinna taty were developed from the enriched (CA)15 genomic library, and they were used for the population genetic studies of the half-fin anchovy from Chinese coastal areas. Samples were collected from five localities of the East China Sea and the Yellow Sea. Eleven simple sequence repeat markers were used to assess genetic differentiation in 30 individuals at each locality. As a result, 59 alleles were recorded over all loci with an average of 5.36 alleles per locus. Observed and expected heterozygosities ranged from 0.27 to 0.73 and 0.50 to 0.89, respectively. Analysis of molecular variation indicated that the variation within individuals was high (70.68%), while variations of individuals within and among populations were low (22.47 and 6.85%). The phylogenetic tree showed that these populations could be divided into two clusters: populations of the East China Sea, which came from Ninghai, Xiangshan and Zhoushan, and populations of the Yellow Sea, which were from Yantai and Weihai. It revealed that significant geographic structure existed in this species. All of the results indicated that high genetic diversity existed in the half-fin anchovy from different geographic populations. This conclusion was consistent with the classification based on morphological and physiological characteristics.

Predicted infiltration for sodic/saline soils from reclaimed coastal areas: sensitivity to model parameters.

This study was conducted to assess the influences of soil surface conditions and initial soil water content on water movement in unsaturated sodic soils of reclaimed coastal areas. Data was collected from column experiments in which two soils from a Chinese coastal area reclaimed in 2007 (Soil A, saline) and 1960 (Soil B, nonsaline) were used, with bulk densities of 1.4 or 1.5 g/cm3. A 1D-infiltration model was created using a finite difference method and its sensitivity to hydraulic related parameters was tested. The model well simulated the measured data. The results revealed that soil compaction notably affected the water retention of both soils. Model simulations showed that increasing the ponded water depth had little effect on the infiltration process, since the increases in cumulative infiltration and wetting front advancement rate were small. However, the wetting front advancement rate increased and the cumulative infiltration decreased to a greater extent when θ 0 was increased. Soil physical quality was described better by the S parameter than by the saturated hydraulic conductivity since the latter was also affected by the physical chemical effects on clay swelling occurring in the presence of different levels of electrolytes in the soil solutions of the two soils.

Sixty-Year Sedimentary Record of DDTs, HCHs, CHLs and Endosulfan from Emerging Development Gulfs: A Case Study in the Beibu Gulf, South China Sea

The temporal distribution of organochlorine pesticides (OCPs) was examined in the (210)Pb dated sediment core from the Beibu Gulf, South China Sea. The total OCPs concentrations were in the range of 0.93-26.6 ng g(-1) dry weight. Dichlorodiphenyltrichloroethanes (DDTs) (0.17-24.8 ng g(-1)), Hexachlorocyclohexanes (HCHs) (0.04-0.51 ng g(-1)), Chlordane related compounds (CHLs) (0.22-1.72 ng g(-1)) and endosulfan (n.d.-0.91 ng g(-1)) were the predominant compounds. Similar to most Chinese coastal areas, the levels of DDTs in the Beibu Gulf became elevated since the early 1990s, especially since 2000 despite the ban in 1983 in China. This suggests that the concentrations of DDTs were controlled by several processes, such as land reclamation and soil runoff. The isomer ratios of (p,p'-DDE + p,p'-DDD)/p,p'-DDT, p,p'-DDT/DDTs along with construction land expansion indicated that economic activities, land reclamation, soil runoff and the use of DDT-containing antifouling paints might be responsible for the input of DDT. The ratios of α-HCH/γ-HCH (and γ-HCH/HCHs) and trans-chlordane/cis-chlordane (TC/CC) indicated fresh inputs of lindane and chlordane, respectively. In addition, CC was found to be degraded faster than TC under anaerobic conditions in sediments from the Beibu Gulf.

Hydroxylated and methoxylated polybrominated diphenyl ethers in mollusks from Chinese coastal areas

Hydroxylated polybrominated diphenyl ethers (OH-PBDEs), methoxylated PBDEs (MeO-PBDEs) and PBDEs were determined in three mollusk species collected from three Chinese coastal regions in 2007, 2009, 2010 and 2011. The dominant MeO- and OH-PBDEs isomers detected in mollusks were 6-MeO-BDE-47, 2′-MeO-BDE-68, 6-OH-BDE-47 and 2′-OH-BDE-68. Concentrations of ΣMeO-PBDEs ranged from 9.20 to 2090pgg−1 dry weight (mean: 450pgg−1 dry weight). Concentrations of ΣOH-PBDEs ranged from 118 to 2540pgg−1 dry weight (mean: 534pgg−1 dry weight). Species differences in accumulation were found for the three mollusk species. Spatial distribution showed that OH- and MeO-PBDEs levels were higher in Weihai than in Tianjin. The temporal trends of OH- and MeO-PBDEs in mollusks were studied during period of 2007 to 2011, rising of ΣOH-PBDEs in Rap from Penglai and Ost from Weihai and declining of ΣMeO-PBDEs in Ost in Penglai were observed. Significant correlations were found between OH- and MeO-PBDEs, but neither between PBDEs and OH-PBDEs, nor between PBDEs and MeO-PBDEs, suggesting that OH- and MeO-PBDEs may have a common source or similar accumulation behavior in mollusks. OH- and MeO-PBDEs were likely not to originate from PBDE precursors.

Development and application of a method for determination of nucleosides and nucleobases in Mactra veneriformis

Background:Mactra veneriformis, a typical marine bivalve mollusk, delicious sea food while low cost, is ubiquitous and abundant in Chinese coastal areas, especially in the coastal shoals of Jiangsu province. To our knowledge, previously reported analytical methods can not meet a set of quality control.Objective:For the simultaneous determination of eight components (uridine, inosine, guanosine, thymidine, adenosine, xanthine, thymine and hypoxanthine) in M. veneriformis, a high performance liquid chromatography with UV detector method was established.Materials and Methods:To develop the method, a reverse phase column, BioBasic-C18 (5 μm, 4.6 mm × 250 mm) was used. The mobile phase consisted of methanol and water using a gradient elution. The UV wavelength was set at 245 nm. The analysis conditions including extraction methods, extraction solvents, and HPLC parameters were optimized systematically for achieving good separation. Linearity, accuracy, repeatability and detection limit was revealed and showed good performance.Results:The optimized HPLC method was successfully applied for the qualititation of 5 nucleosides namely, uridine, inosine, guanosine, thymidine, adenosine and 3 nucleobases namely, xanthine, thymine, hypoxanthine in M. veneriformis.Conclusion:A method with less time-consuming, more sensitive, and more precise was developed for the quantitative determination of nucleosides and nucleobases in M. veneriformis extractions. The established method might apply as an alternative approach for the quality assessment of M. veneriformis.

Interannual Sea Level Variations in the South China Sea Over 1950–2009

Spatial patterns of interannual sea level variations in the South China Sea (SCS) are investigated by analyzing an EOF-based 2-dimensional past sea level reconstruction from 1950 to 2009 and satellite altimetry data from 1993 to 2009. Long-term tide gauge records from 14 selected stations in this region are also used to assess the quality of reconstructed sea levels and determine the rate of sea level along the coastal area. We found that the rising rate of sea levels derived from merged satellite altimetry data during 1993–2009 and past sea level reconstruction over 1950–2009 is about 3.9 ± 0.6 mm/yr and 1.7 ± 0.1 mm/yr, respectively. For the longer period, this rate is not significantly different from the global mean rate (of 1.8 ± 0.3 mm/yr). The interannual mean sea level of the SCS region appears highly correlated with Niño 4 indices (a proxy of El Niño-Southern Oscillation/ENSO), suggesting that the interannual sea level variations over the SCS region is driven by ENSO events. Interpolation of the reconstructed sea level data for 1950–2009 at sites where tide gauge records are of poor quality (either short or gapped) show that sea level along the Chinese coastal area is rising faster than the global mean rate of 1.8 mm/yr. At some sites, the rate is up to 2.5 mm/yr.

Chemical Composition and Antioxidant/Antimicrobial Activities in Supercritical Carbon Dioxide Fluid Extract of Gloiopeltis tenax

Gloiopeltis tenax (G. tenax) is widely distributed along the Chinese coastal areas and is commonly used in the treatment of diarrhea and colitis. This study aimed at investigating the bioactivities of the volatile constituents in G. tenax. We extracted the essential constituents of G. tenax by supercritical carbon dioxide extraction (CO2-SFE), then identified and analyzed the constituents by gas chromatography-mass spectrometry (GC-MS). In total, 30 components were identified in the G. tenax extract. The components showed remarkable antioxidant activity (radical scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH)), lipid peroxidation inhibition capacity (in a β-carotene/linoleic acid-coupled oxidation reaction), and hydroxyl radical-scavenging activity (by deoxyribose degradation by iron-dependent hydroxyl radical), compared to butylated hydroxytoluene. In microdilution assays, G. tenax extracts showed a moderate inhibitory effects on Staphyloccocus aureus (minimum inhibitory concentration (MIC) = 3.9 mg/mL), Enterococcus faecalis (7.8 mg/mL), Pseudomonas aeruginosa (15.6 mg/mL), and Escherichia coli (3.9 mg/mL). Antioxidant and antimicrobial activities of G. tenax were related to the active chemical composition. These results suggest that the CO2-SFE extract from G. tenax has potential to be used as a natural antioxidant and antimicrobial agent in food processing.