The study on fishing ground of neon flying squid, Ommastrephes bartrami,and ocean environment based on remote sensing data in the Northwest Pacific Ocean

The relationships between the neon flying squid, Ommastrephes bartrami, and the relative ocean environmental factors are analyzed. The environmental factors collected are sea surface temperature (SST), chlorophyll concentration (Chl-a) and sea surface height (SSH) from NASA, as well as the yields of neon flying squid in the North Pacific Ocean. The results show that the favorable temperature for neon flying squid living is 10°C–22°C and the favorite temperature is between 15°C–17°C. The Chl-a concentration is 0.1–0.6 mg/m3. When Chl-a concentration changes to 0.12–0.14 mg/m3, the probability of forming fishing ground becomes very high. In most fishing grounds, the SSH is higher than the mean SSH. The generalized additive model (GAM) was applied to analyze the correlations between neon flying squid and ocean environmental factors. Every year, squids migrate northward from June to August and return southward during October–November, and the characteristics of the both migrations are very different. When squids migrate to the north, most relationships between the yields and SST are positive. The relationships are negative when squids move to southward. The relationships between the yields and Chl-a concentrations are negative from June to October, and insignificant in November. There is no obvious correlation between the catches of squid and longitude, but good with latitude.

Evaluation and fusion of SST data from MTSAT and TMI in East China Sea, Yellow Sea and Bohai Sea in 2008

Two typical satellite sea surface temperature (SST) datasets, from the Multi-functional Transport Satellite (MTSAT) and Tropical Rainfall Measuring Mission Microwave Imager (TMI), were evaluated for the East China Sea, Yellow Sea, and Bohai Sea throughout 2008. Most monthly-mean availabilities of MTSAT are higher than those of TMI, whereas the seasonal variation of the latter is less than that of the former. The analysis on the one-year data shows that the annual mean availability of MTSAT (61%) is greater than that of TMI (56%). This is mainly because MTSAT is a geostationary satellite, which achieves longer observation than the sun-synchronous TMI. The daily availability of TMI (28%-75%) is more constant than that of MTSAT (9%-93%). The signal of infrared sensors on MTSAT is easily disturbed on cloudy days. In contrast, the TMI microwave sensor can obtain information through clouds. Based on in-situ SSTs, the SST accuracy of TMI is superior to that of MTSAT. In 2008, the root mean square (RMS) error of TMI and MTSAT were 0.77 K and 0.84 K, respectively. The annual mean biases were 0.14 K (TMI) and -0.31 K (MTSAT). To attain a high availability of SSTs, we propose a fusion method to merge both SSTs. The annual mean availability of fusion SSTs increases 17% compared to MTSAT. In addition, the availabilities of the fusion SSTs become more constant. The annual mean RMS and bias of fusion SSTs (0.78 K and -0.06 K, respectively) are better than those of MTSAT (0.84 K and -0.31 K).

Otolith chemical signatures of spottedtail goby Synechogobius ommaturus in coastal waters of China

This study explores the potential existence of local stocks of Synechogobius ommaturus using otolith chemical signatures. The concentrations of 10 elements (K, Ca, Na, Mg, Sr, Pb, Ba, Mn, Co, Zn) in the otoliths from eight stocks (Dandong, Dalian, Tianjin, Dongying, Weihai, Qingdao, Ganyu and Xiamen) of S. ommaturus were measured by Inductively Coupled Plasma Mass Spectrometry and regressed against otolith weight. No significant correlation between otolith weight and concentrations of Na, Mg, Ca, Sr, Co, Ba, Zn and Pb were observed. Concentrations of K and Mn were correlated with otolith weight. Consequently, the residuals of the regressions were used instead of the original concentrations in subsequent analyses. Analysis of variance (ANOVA) showed no significant difference between males and females in otolith chemical signatures. Differences were found among the locations for K, Sr, Mn, Co, Ba, Pb, but not for Ca, Na, Mg and Zn. Residuals of the regressions of elemental concentrations against otolith weight that fitted the normal distribution and homogeneity were studied by discriminant analysis. The success of the discriminant function to predict the location of S. ommaturus capture ranged from 100% for Weihai and Xiamen stocks, to only 44.4% and 62.5% for Qingdao and Dandong stocks, respectively. The average prediction success was 80.3%.

Analysis of SSRs Derived from an EST Library of Half-Smooth Tongue Sole Cynoglossus semilaevis

A complementary DNA(cDNA) library was constructed from half-smooth tongue sole spleen. A long-read expressed sequence tag(EST) database was generated,containing 3100 cDNA clones,of which 220 clones were fully sequenced. A total of 1060 non-redundant simple sequence repeats(SSRs) were obtained from the cDNA library. An average of 5 kb sequence generates 1 SSR in the half-smooth tongue sole spleen cDNA library. The proportion of the SSR unit size was different in the cDNA library. The monomeric repeats(51.4%) are the most abundant class of SSR in the dataset. The dimeric,trimeric,tetrameric and hexameric re-peats are represented in decreasing proportions of 27.2%,16.0%,2.8% and 1.9%,respectively. The frequency of pentameric repeats was observed the least(only 0.7%) . Most of the monomeric and dimeric repeats are distributed in 3' and 5' un-translation region. If translation regions are considered merely,trimeric repeats are the highest,accounting for 57% of the total microsatellites.

Statistical analysis on ecological adaptation of pelagic Amphipoda in the East China Sea

This article studied the diversity of Amphipoda＇s environmental adaptation using statistic method- ology based on the seasonal investigation data obtained from the East China Sea waters （23°30′- 33°N, 118°30′128°E） from 1997 to 2000. Fifty-four Amphipoda species were identified： among which eight species could stand a temperature difference over 10 ℃ and eight species could tolerate the temperature gap ranged from 5 to 10 ℃; while only six species could stand the salinity fluctuation more than 5. Based on above facts as well as calculated optimal temperature and salinity we divided all Amphipoda species into four groups： （1） eurythermic and euryhalinous species including Lestrigonus schizogeneios, L. macrophthalmus, Tetrathyrus forcipatus, L. bengalensis and Hyperi- oides sibaginis; （2） temperate-warm species containing Hyperoche medusarum, Parathemisto gau- dichaudi, Themisto japonica and Hyperia galba; （3） oceanic tropical species consisted of Oxycephalus clausi~ Lyeaea pulex, Eupronoe minuta, Simorhychotus antennarius, O. poreelus, Platyscelus ovoides and Rhabdosoma ahitei; （4） subtropical species involving one nearshore subtropical water species （Corophium uenoi） and 37 offshore subtropical ones. Compared with other zooplankton such as Eu- phausia and Chaetognatha, Amphipoda was characterized by low dominance but wide distribution in the East China Sea, and this could be ascribed to its high adaptation diversity.