First record of abnormal body coloration in a rockfish Sebastes koreanus(Scorpaenoidei:Sebastidae)from coastal water of China based on morphological characteristics and DNA barcoding

The first record of abnormal body coloration in Sebastes koreanus Kim and Lee,1994,from the Yellow Sea of China,was documented based on morphological characteristics and DNA barcoding.The two rockfish specimens were collected from the coastal waters of Qingdao,China,and the whole body and all fins of them were red.Of the two red-colored rockfish,there were tiny deep red spots on each fin,2 red radial stripes behind and below the eyes and 1 large deep red blotch on the opercula,while the similar stripe and spot patterns are also present in the S.koreanus specimens with normal body coloration.The countable characteristics of the two specimens are in the range of the morphometry of S.koreanus.To further clarify the species identity and taxonomic status of the two specimens,DNA barcode analysis was carried out.The genetic distance between the red-colored rockfish and S.koreanus was 0,and the minimum net genetic distances between the red-colored rockfish and other Sebastes species except for S.koreanus were 3.0%,which exceeds the threshold of species delimitation.The phylogenetic analysis showed that the DNA barcoding sequences of the two red-colored rockfish clustered with the S.koreanus sequences.The above results of DNA barcode analysis also support that the two red-colored rockfish could be identified as the species of S.koreanus.The mechanism of color variation in S.koreanus is desirable for further research and the species could be an ideal model to study the color-driven speciation of the rockfishes.

Atmospheric Correction of SeaWiFS Data for the Retrieval of SuspendedSediment in East China Coastal Waters

The data of SeaWiFS (Sea-Viewing Wide Field-of-View Sensor), installed on SeaStar, has been used to generate SSC (suspended sediment concentration) of complex and turbid coastal waters in China. In view of the problems of the SeaDAS (SeaWiFS Data Analysis System) algorithm applied to China coastal waters, a new atmospheric correction algorithm is discussed, developed, and used for the SSC of East China coastal waters. The advantages of the new algorithm are described through the comparison of the results from different algorithms.

Fouling community characteristics in subtropical coastal waters of the southwestern East China Sea

A fouling study was conducted in coastal waters southwest of the East China Sea between December 2013 and November 2014. A total of 84 species of fouling organisms belonging to 69 genera, 49 families, and 10 phyla were recorded over the entire year. The community composition was dominated by coastal warm-water species belonging to typical subtropical inner bay communities. The prosperous stage of settlement lasted from April to September, and the adhesion strength of the fouling organisms was the highest in summer. Sessile suspension feeders constituted the main core of settlement for the fouling community. Amphibalanus reticulatus was the most dominant and representative species of fouling organism, and other dominant species included Caprella equilibra, Ectopleura crocea, Anthopleura nigrescens, Stylochus ijimai, Spirobranchus kraussii, Crassostrea angulata, Perna viridis, Jassa falcata, Stenothoe valida, Sphaerozius nitidus, and Biflustra grandicella. The individuals in the fouling community showed a mutual dependence or constraint relationship due to competition for settlement space and food, and they exhibited a particular spatiotemporal distribution in accordance with adaptation to environmental factors. Temperature was the most important environmental factor determining the geographic distribution of fouling organisms. The temperature characteristics of species essentially reflect the differences in the fouling community composition in various climate zones. The species number, settlement stage, and settlement rate of fouling organisms are closely related to water temperature. Local natural environmental conditions（salinity, water currents, light, etc.） as well as human activity（such as aquaculture production） are all important factors affecting the settlement of fouling organisms.

Study on copper complexing ligand concentrations in several China's coastal waters

Copper complexing ligand concentrations in the Daya Bay, Qingdao coast, Jiaozhou Bay, South China Sea and Huanghe Estuary waters were determined by the anodic stripping voltammetry technique. The distribution regularity and the relationship with other parameters were discussed. The results were as follows： Copper complexing ligand concentrations of the South China Sea were a little higher than those of other sea areas, and they were apparently higher than those of the ocean. Compared with the subsurface layer （SSL） in the sea surface microlayer copper complexing ligand concentrations showed an enrichment phenomenon, of which the mechanism is similar to dissolved organic matter. The metal complexing ligand concentration profiles of the South China Sea showed that the value in the sea surface was the highest, then it decreased with depth accruing, and a higher value appeared at the bottom. Copper complex- ing ligand concentrations were higher than those of cadmium and lead. Ligands in each sea area exhibited a complicated property. In short, the distribution regularity of copper complexing ligand concentrations in China＇s coastal waters was consistent with that of other regions in the world. Meanwhile, the positive relationship between the copper complexing ligand concentrations and biological oxygen demand, chemical oxygen demand, dissolved organic carbon, and viscosity were found clearly.

The“harmful algae and algal toxins in coastal waters of China:investigation and database”project

The“harmful algae and algal toxins in coastal waters of China:investigation and database”project(HAATC)is funded(US$2.3 million)by the Ministry of Science and Technology of China for 60 months starting on the 1st Jan 2019.Since the 1990s,national projects and other related work have greatly improved harmful algal bloom(HAB)research in China.However,the existing research on HABs is often limited to specific sea areas or specific algal bloom disasters,which is insufficient for understanding the long-term evolution of HAB occurrence under the influence of intensified human activity and global change.The HAATC project intends to determine the overall distribution of marine harmful microalgae and macroalgae,and marine algal toxins(in phytoplankton and shellfish)through a large-scale investigation in the coastal waters of China and continuous investigation in key sea areas.It also aims to observe biotic and abiotic processes during harmful red tides and green tides,and establish an open database and query platform of HABs in China.The research consortium,led by chief scientist Prof.Tian YAN,includes approximately 100 scientists and students.More than 2 years of work have shown the increased distribution of HAB species(including cysts)and algal toxins in China’s coastal waters,the increased occurrence of macroalgae blooms(mainly by Ulva prolifera and Sargassum horneri)in the Southern Yellow Sea,increased amount of causative species being identified due to the use of molecular technologies in taxonomy,and new records of algal toxins such as azaspiracid,cycloimines and neurotoxinsβ-N-methylamino-l-alanine have been detected,which complicates the research in algal toxins and toxicology.Eventually,the project will provide systematic basic data and techniques for the rapid and accurate identification of harmful algae species to support the research,monitoring,and control of harmful algal blooms,as well as seafood safety management in China.

Morphological and genetic comparison of two strains of a Prorocentrum species isolated from Zhejiang coastal water of China and Masan Bay of Korea

In this paper, we examined the detailed morphology of two strains of Prorocentrum isolated from the coastal waters of Zhejiang (Wenling area), China, and Masan Bay of Korea. A taxonomic comparison was made among strains on the basis of morphological and molecular data. The cellular dimensions of the Chinese Wenling strain (LAMB090508) and Korean strain (PDKS0206) were similar and the cells of both strains were of asymmetric and elongated shape. The posterior end of most cells was rounded. Megacytic zones of aged cells were broader with dense tiny knobs. The roundish nucleus was located in the posterior part of the cell. A few irregular shaped chloroplasts were distributed within the cell. The nucleotide similarity of the two strains, determined from the 5.8S rDNA-ITS sequences, was 99.83%. The comparative results of morphology and molecular analysis suggest that both strains isolated from China and Korea were the identical species, Prorocentrum donghaiense Lu.

A new record of Sebastes koreanus from China based on morphological characters and DNA barcoding

A new record of Sebastes koreanus （Kim and Lee, 1994） was documented based on morphological characters and DNA barcoding. Fifty-six Sebastes specimens were collected from the coastal waters of northern China. Samples were identified as S. koreanus based on morphological characters. The coloration and morphometric measurements were consistent with those described from specimens collected in South Korea. In this study, specimens had the following morphological characteristics： light brown body with dark stripes and tiny dark spots, 4-5 wide indistinct vertical patterns on the side, 2 radial stripes behind and below the eyes, 1 large dark blotch on the opercle. Additionally, the following meristie characters were recorded： dorsal fin XIV-13, pectoral fin 16, anal fin III-6-7, pelvic fin [-5, lateral line scales 29-30, and vertebrae 26. The fragment of cytochrome oxidase subunit I （CO1） gene of mitochondrial DNA was sequenced for phylogenetic analysis. The mean genetic distance within the species was 0.3%. Net genetic distances between S. koreanus and other Sebastes species ranged from 3.1% to 7.6%, which was greater than the threshold for species delimitation. The phylogenetic analysis strongly supports the validity of S. koreanus in China at the genetic level. The origion, evolution, patterns of speciation and unique features in genome divergence among primate lineages of this species still need future directions of research.

Phaeocystis globosa Scherffel,a harmful microalga,and its production of dimethylsulfoniopropionate

The production of dimethylsulfoniopropionate （DMSP） and its cleavage products （DMS） are well studied in phytoplankton worldwide. However, less is known about their sources, distributions, and impacts in the coast of China. We examined the production of DMSP and DMS in Phaeocvstis globosa Scherffel and other benthic macroalgae from the South China coast in relation to environmental conditions. P. globosa was a harmful marine microalgal species and its bloom took place in the eutrophic waters along the South China Sea frequently. It also produced high content of DMSP at different growth stages, with the highest concentration usually observed in the stationary period. Moreover, the production of DMSP in P. globosa was significantly affected by salinity and temperature with the highest contents associated with high salinity （e.g. 40） and low temperature （e.g. 20℃）. In field benthic macroalgae, there was also a marked difference in the DMSP of various species or different samples of the same species. Chlorophyll a contents were also determined for each macroalgal species. The highest chlorophyll a （238.7 ng/g fresh weight） was recorded in Chlorophyta Ulva lactuca at Guishan Island （Zhuhai）, while the lowest value （1.5 ng/g fresh weight） was found in Rhodophyta Gracilaria tenuistipitata in Zhanjiang. Further correlation analysis indicated that there was no significant relationship between the content of DMSP and chl-a in macroalgae samples （P〉 0.05）. All the results suggested that the production of DMSP in marine algae was not only species- and stage-related, but also greatly affected by various environmental factors.

Implementing geostatistical analysis to study spatio-temporal distribution patterns of swimming crabs(Portunus trituberculatus)

This study attempted to compare the performance of local polynomial interpolation,inverse distance weighted interpolation,and ordinary kriging in studying distribution patterns of swimming crabs.Cross-validation was used to select the optimum method to get distribution results,and kriging was used for making spatial variability analysis.Data were collected from 87 sampling stations in November of 2015(autumn)and February(winter),May(spring)and August(summer)of 2016.Results indicate that swimming crabs widely distributed in autumn and summer:in the summer,they were more spatially independent,and resources in each sampling station varied a lot;in the winter and spring,the abundance of crabs was much lower,but the individual crab size was bigger,and they showed the patchy and more concentrative distribution pattern,which means they were more spatially dependent.Distribution patterns were in accordance with ecological migration features of swimming crabs,which were affected by the changing marine environment.This study could infer that it is applicable to study crab fishery or even other crustacean species using geostatistical analysis.It not only helps practitioners have a better understanding of how swimming crabs migrate from season to season,but also assists researchers in carrying out a more comprehensive assessment of the fishery.Therefore,it may facilitate advancing the implementation in the pilot quota management program of swimming crabs in northern Zhejiang fishing grounds.