Dynamics of Dimethylsulfide and Dimethylsulfoniopropionate Produced by Phytoplankton in the Chinese Seas - Distribution Patterns and Affecting Factors

Distribution of dimethylsulfide (DMS) and/or particulate dimethylsulfoniopropionate (DMSPp) concentrations in the Jiaozhou Bay, Zhifu Bay and East China Sea were investigated during the period of 1994 - 1998. Both DMS and DMSPp levels showed remarkable temporal and spatial variations. High values occurred in the coastal or shelf waters and low values in the offshore waters. The highest levels were observed in spring or summer and lowest in autumn. DMS or DMSPp distribution patterns were associated with water mass on a large geographical scale, while biological and chemical factors were more likely influential on smaller-scale variations. Diatoms could play an important role in total DMS or DMSPp abundance in coastal waters. Nitrate was found to have a two-phase relationship with DMSPp concentrations: positive when nitrate concentration was lower than 1 mumol/L, and negative when it was above. Anthropogenic factors such as sewage input and aquaculture also showed influences on DMS or DMSPp concentration.

Diversity and geographical distribution of haptophyte Phaeocystis in the Chinese seas based on metabarcoding analysis

Phaeocystis is an important bloom-forming species and over 100 blooms have occurred since 1997 along the Chinese coasts,while only the species P.globosa was described.In this project,a total of 246 phytoplankton samples collected from the Bohai Sea,the Yellow Sea,and the East China Sea in April 2021 were analyzed to evaluate the species diversity and geographical distribution of the genus Phaeocystis based on metabarcoding 18S r DNA sequence.Four described Phaeocystis species were recognized,including P.globosa,P.pouchetii,P.jahnii,and P.cordata,and each has distinguished geographical distribution characteristics.P.globosa was the most widespread and abundant species,and P.pouchetii was found in the Bohai Sea and the northern Yellow Sea with substantially elevated abundance.P.cordata was also a widespread species,but its abundance was relatively low,while P.jahnii gathered only in the southeastern East China Sea.Water temperature,phosphate as well as ammonium contents were found to be associated with the abundance of P.globosa,P.pouchetii,and P.jahnii significantly.Moreover,two uncharacterized Phaeocystis species were detected in the Chinese seas,indicating the diversity of the genus remains underestimated worldwide.

A new record of blue-spotted seabream Pagrus caeruleostictus from Chinese coastal waters documented from morphology and DNA barcoding

A new record of Pagrus caeruleostictus(Valenciennes,1830),collected from the Beibu Gulf,South China Sea in April 2013,was documented based on morphology and cytochrome oxidase I subunit(COI) gene barcoding analyses. It can be distinguished by a combination of the following characteristics: head scaled to above eyes; cheeks with 5 or 6 rows of scales; lateral line scales 51–52; 5 rows of scales above the lateral line; 4 and 6 cuspidate teeth in front of upper and lower jaws,respectively,followed by 2 rows of blunter teeth posteriorly; gill rakers on first arch 12 to 15; D XI–XII +9–11; A III +8–9; the first two dorsal spines very short,the third to fifth extended,filamentous in the young; the first pelvic ray filamentous; silvery pink with dark blue spots on back and sides; caudal fin pinkish; other fins bluish or pinkish; the blue spots generally disappear in large specimens. The present report of P. caeruleostictus suggests that its distribution in Chinese coastal waters may be attributed to human effort,since this species is unlikely to have expanded naturally from the eastern Atlantic to the South China Sea,with no other records from the Indian or Pacific Oceans. We recommend that a precautionary approach should be adopted for the management of P. caeruleostictus.

Riding the Sea and Chasing the Wave Chinese Ceramics Sold to Europe in the Ming and Qing Dynasties(II)

正Orders from Europe: Features of Chinese Export Porcelain Chinese porcelain was first imported to Europe by Portuguese traders. However, the glossy ware was not supposed to be profitable and was bought as ballast for silk, lacquer ware, spice, and other dearly cargos.

Advances in GDGT research in Chinese Marginal Seas: A review

Archaeal and bacterial glycerol dialkyl glycerol tetraethers(GDGTs) play a unique role in discerning the biogeochemical processes and climate change in terrestrial(e.g. soil, peat, stalagmites, lakes, rivers, hot springs) and marine environments. Organic proxies based on GDGTs(e.g. TEX_(86), MBT/CBT and BIT) have made impressive applications in the open ocean and terrestrial environments. However, the applicability of these proxies in marginal seas has not been thoroughly evaluated, which is necessary given the complexity and dynamics of these systems, such as organic matter(OM) flux, hydrodynamic conditions, and human impact. This review aims to summarize recent studies of GDGTs and GDGT-based proxies in the Chinese marginal seas(CMS), which are characterized by diverse gradient in terrigenous supplies and ocean productivity and hold rich information on climate and sea level changes, ocean current dynamics, sedimentary evolution and biogeochemical processes.

Phylotype resolved spatial variation and association patterns of planktonic Thaumarchaeota in eastern Chinese marginal seas

The majority of marine ammonia oxidizers belong to Thaumarchaeota,a phylum of Archaea,which is distributed throughout the water column.Marine surface waters contain distinct thaumarchaeotal phylotypes compared to the deeper ocean,but spatial dynamics of the surface-associated lineages are largely unsolved.This study of 120 seawater samples from the eastern Chinese marginal seas identifed contrasting distribution and association patterns among thaumarchaeotal phylotypes across diferent dimensions.Horizontally,Nitrosopumilus-like and Nitrosopelagicus-like phylotypes dominated the surface water(3 m)of the Yellow Sea(YS)and East China Sea(ECS),respectively,along with increased abundance of total free-living Thaumarchaeota in ECS.Similar compositional changes were observed in the surface microlayer.The spatial heterogeneity of particle-attached Thaumarchaeota was less clear in surface microlayers than in surface waters.Vertically,the Nitrosopelagicus-like phylotype increased in abundance from surface to 90 m in ECS,which led to an increase in the proportion of Thaumarchaeota relative to total prokaryotes.This occurred mainly in the free-living fraction.These results indicate a clear size-fractionated niche partitioning,which is more pronounced at lower depths than in the surface water/surface microlayer.In addition,associations of Thaumarchaeota with other microbial taxa varied between phylotypes and size fractions.Our results show that a phylotype-resolved and size-fractionated spatial heterogeneity of the thaumarchaeotal community is present in surface oceanic waters and a vertical variation of the Nitrosopelagicus-like phylotype is present in shallow shelf waters.

Comparison for ecological economic performance of Chinese sea perch(Lateolabrax Maculatus)under different aquaculture systems

Chinese sea perch(Lateolabrax Maculatus)is one of the main marine fish culture species in China,its green development has received increasing attention and its ecological economic study is rare.Based on field survey,this paper takes water pollution tax of China as conversion indicator for aquaculture eutrophication to simulate aquaculture waste fee for further analyzing the ecological impact of Chinese sea perch’s aquaculture.For data analysis,data envelopment analysis model has been used.The comparison for Chinese sea perch’s economic performance and ecological economic performance under its main aquaculture systems has been done.The results show that:1.The simulated waste fee has no significant impact for the comparison.2.Ranking for ecological economic performance’s ecological economic,technical and scale efficiency is as follow:pond farming,offshore cage culture and cage culture.3.Offshore cage culture is the only system presenting positive increase for ecological economic performance,which makes its aquaculture activity more sustainable than other systems.4.The key point of green development is to maximize the ecological economic efficiency of main aquaculture systems.Thus,offshore cage culture is the most sustainable aquaculture system among China’s current marine fish culture systems,and other systems need innovation for achieving the green development of China’s aquaculture.