The 3D numerical model of the Changjiang Estuary built in the series paper Ⅱ was used to simulate the saltwater intrusion in 1950s, 1970s and 2012, and the changes of saltwater intrusion under different river regimes and their reasons were analyzed quantitatively in this paper. In the North Branch, the saltwater intrusion were controlled by the water diversion ratio and tidal range. In 1950s and 2012, saltwater spilled over from the North Branch to the South Branch and the magnitude was greater during spring tide than during neap tide, and was greater in 2012 than in 1950s. This phenomenon didn't appear in 1970s. In 1950s, saltwater intrusion was severe in the North Branch. In 1970s, it decreased greatly, and a large amount of fresh water appeared in the upper and middle reaches. In 2012, the saltwater intrusion was very severe and the whole North Branch was occupied by saltwater, sharp salinity front appeared in the upper reaches. In the South Branch, fresh water occupied the most area in 1950s and 1970s, and in 2012 saltwater with salinity greater than 0.45 appeared in the upper reaches because saltwater spilled over from the North Branch. In the North and South Channel, saltwater intrusion in the 1950s was the most severe. During the spring tide, the net water diversion ratio in the North Channel was higher than that that in the South Channel by 21.6%, which caused the salinity in the North Channel was lower than that in the South Channel, resulting in the saltwater from the open sea intruded mainly through the South Channel, and returned over from the South Channel to the North Channel. In 1970s, the mainstream of the South Branch turned to the South Channel, which caused the net water diversion ratio in the South Channel increased, and became higher than that in the North Channel by 10.4%, causing the salinity in the South Channel was lower than that in the North Channel; the saltwater intrusion was weakest in the South and North Channel. In 2012, the mainstream of the South Branch turned to the North Channel again and the net water diversion ratio in the North Channel was higher than that in the South Channel by 10.4%, resulting in the saltwater intrusion in the South Channel greater than that in the North Channel. Comparing with the situation in 1950s, the saltwater intrusion in 1970s was lower in the North and South Channel. Comparing with the situation in 1970s, the saltwater intrusion in 2012 was lower in the North Channel and was higher in the South Channel. During the neap tide, the net water diversion in the South Channel was lower than that that during the spring tide in 1950s, causing the saltwater intruded more farer and the salinity in the upper reaches was higher; in 1970s, the salinity intrusion in the North Channel decreased because of the reduction of the net water diversion ratio; in 2012, the saltwater that spilled over from the North Branch in the spring tide arrived the North Channel, which caused the salt flux in the neap tide being greater than that in the spring tide. The salinity was more stratified in vertical because of the lower tidal dynamics in the three periods, and the changes of saltwater intrusion was almost same as that during the spring tide.

Submarine groundwater discharge (SGD) with inputs of nutrients and water into the ocean in certain regions plays a significant role in coastal material fluxes and their biogeochemical cycle, which cannot be ignored for its impact on the eco-system. In this paper, SGD into the typical aquaculture base of northern China, Sanggou Bay, was estimated using naturally occurring radium isotopes, ²²³Ra and ²²⁴Ra. Results showed that the radium activities of submarine groundwater, especially in the pore water [²²⁴Ra=(968±31) dpm/(100 L), ²²³Ra=(31.4±4.9) dpm/(100 L), n=9], were obviously greater than those in the surface water [²²⁴Ra=(38.7±2.0) dpm/(100 L),²²³Ra=(1.70±0.50) dpm/(100 L), n=21]. Assuming steady state and using a radium mass balance model with sources and sinks, the SGD rate was estimated to be among (0.23~1.03) ×10⁷ m³/d. SGD flux varied from spring tide to ebb tide. During spring tide, SGD flux was smaller because of weak hydraulic gradient while it was much larger during ebb tide because of strong hydraulic gradient. During a tidal cycle, the SGD flux was averaged to be 0.39×10⁷ m³/d based on ²²³Ra and ²²⁴Ra. Tidal-driven SGD can account for 61% of the total SGD. Therefore, the main driving force of SGD into Sanggou Bay was tidal pumping and SGD of Sanggou Bay in coastal zone contributes a lot to seawater composition and material exchange between land and sea.

Two core sediment were collected in the Changjiang Estuary and its adjacent area as study areas. The SEDEX method was applied to determined the forms of phosphorus in the sediments. Effects of sediment resuspension on the phosphate in the water column was studied. The results indicated that Detrital P was the highest form, which accounted for above 50% of TP. The contents of organic P and refractory P were also higher than other forms. Bioavailable P was accounted for 21% of TP. Organic P was the major part of bioavailable P. The concentrations of phosphate in overlying water was significantly higher when sediment resuspension occurred. It shows that sediment resuspension can cause the phosphourus in sediment to release. The increase of phosphate concentration in water mainly comes from the release of phosphorus in sediments. And the contribution of phosphate interstitial water is less than sediments. In addition, It is more favorable to the release of phosphorus in sediment resuspension in the anaerobic condition than that in the aerobic condition.

Sediment samples and pore water were collected in the adjacent area of Changjiang Estuary in June and August of 2011. The study discussed the distribution characteristics and influencing factors of biogenic silica (BSi) in the sediments and the dissolved silicate (DSi) in the pore water, and the cycle and conservation of biological silicon. The results showed that the content of BSi in the surface sediment was less than 1%. The range of concentration of BSi in core sediments was 0.34%-0.52%. The distribution of BSi in C3 and D1 core sediments was controlled by early diagenesis. That of 33^# core sediment was mainly caused by the changes of hydrodynamic condition. The range of concentration of DSi in pore water was 101.6-263.9 μmol/L, which was lower than the solubility of silica. The higher pH in pore water, lower moisture content and higher reduction of sediments lead the higher concentration of DSi in pore water. The higher silica burial efficiency in these stations showed that the adjacent area of Changjiang Estuary was the potential sink of silica. The distribution of silica sedimentation flux was in a decreasing trend from coastal water to the open sea, which was similar to the distribution of silica deposition rate and silica burial efficiency.

Interleukin-10 (IL-10) is a central anti-inflammatory cytokine that demonstrates immunosuppressive function. In this research, an interleukin-10 (IL-10) homologue has been identified by analyzed the genomic data of large yellow croaker (Larimichthys crocea). Subsequently, the open reading frame (ORF) of cDNA and the genomic DNA sequences have been cloned and analyzed. The genomic DNA of large yellow croaker IL-10(LycIL-10) consisted of 1 869 bp that contains five exons and four introns, sharing the same organization with mammalian IL-10 genes. The open reading frame of LycIL-10 consisted 555 bp that give a predicted 184 amino acid IL-10 molecule. It contains a predicted signal peptide of 22 amino acids in the N-terminal and a mature peptide of 162 amino acids, which contained the vertebrate IL-10 family signature. The LycIL-10 exhibits a conserved IL-10 motif signature and shares 26.49%-77.01% amino acid sequence identity with other known IL-10. Real-time PCR analysis showed that LycIL-10 was constitutively expressed in all tissues tested, especially in spleen and muscle. The LycIL-10 mRNA transcription level could significantly increase in the spleen and head kidney of large yellow croaker after trivalent inactivated vaccines or poly(I:C) stimulated, indicating that LycIL-10 may be involved in suppressing the inflammatory induced by bacterium or virus in the large yellow croaker.

To study the relationship between body weight and morphological attributes of Lampetra morii and Lampetra japonica, 314 L. morii and 302 L. japonica were selected to measure 8 morphometric attributes including total length(X₁), trunk length(X₂), tail length(X₃), head length(X₄), snout length(X₅), eye length(X₆), length before the first dorsal fin (X₇), head length behind eye (X₈) and body weight(Y), respectively. The correlation index, path coefficients and determination coefficient are calculated with correlation analysis, path analysis and multivariate analysis, respectively. The multiple regression equations are established with morphometric attributes for the body weight reaching level of significance (P<0.05) and the body weight. The results show that the coefficient of variation of Y of L.morii and L.japonica were the highest value than that of variation of morphological attributes, respectively. And the distribution of body weight of L. morii and L. japonica obeyed normal distribution, respectively. The correlation coefficients between morphological attributes and body weight of L. morii and L. japonica were all at extremely significant level(P<0.01), respectively. Partial regression coefficient of X₁, X₄, X₆ and X₈ for body weight of L. morii were significant (P<0.05) and partial regression coefficient of X₁, X₅ and X₈ for body weight of L. japonica reached extremely significant level(P<0.01). And the path coefficients of X₁, X₄, X₆ and X₈ of L.morii were 0.636、0.202、0.060 and 0.105 and the path coefficients of X₁, X₅ and X₈ of L.japonica were 0.730、0.098 and 0.153. The determination coefficients of X₁ for the body weight of L.morii and L. japonica were larger than that of other morphometric attributes, respecively. The high value of correlation index between morphometric attributes and body weight of L.morii and L.japonicai were 0.855 (r²) and 0.857 (r²), respectively. The multiple regression equations of L. morii and L. japonica were Y=1.502X₁+2.699X₄+8.554X₆+1.915X₈-41.547 and Y=4.895X₁+9.688X₅+6.973X₈-157.460, respectively. In the selection process, total length, head length, eye length and head length behind eye of L. morii and total length, snout length and head length behind eye of L. japonica were considered as a whole, which provided essential theoretical basis and ideal measure for selective breeding of lamprey.

Skipjack is one of the important tuna species in the Indian Ocean, and the relationship between resource abundance and marine environment is very close. In this paper, according to the production statistics of skipjack for tuna purse seine in the Indian Ocean during 1980 to 2010, marine environmental factors and El Niño Southern Oscillation (ENSO) index, the spatial distribution skipjack resources for tuna purse seine fishery in the Indian Ocean, and its relationship with marine environmental factors were analyzed during El Niño and La Niña years. The results showed that the increasing trend of catches from 1980 to 2010 for skipjack purse seine in the Indian Ocean was remained, but the value of CPUE varied greatly, the lowest is only 0.68 t/d (1997), the highest reached 1.58 t/d (2002). At the same time, the skipjack resource abundance (CPUE) and Niño3.4 index had significant negative correlation, that is during El Niño years, the CPUE decreased, while during La Niña years, CPUE increased. ENSO phenomenon also greatly affected fishing ground distribution of skipjack. During El Niño occurence, the center of gravity for skipjack fishing ground moves eastward and northward, while during La Niña years the center of gravity for skipjack fishing ground moves westward and southward.

Anchoveta (Engraulis ringens) is one of the important small pelagic species living in the southeast Pacific Ocean. Exploring the process that fishing grounds vary with oceanic environmental factors could help us to understand the variations in fish stocks, which is beneficial for fishing industry. In this study, based on the Peruvian fishery logbooks of anchoveta from 2005 to 2014 as well as sea surface temperature (SST) data, we developed the fishing ground index (FGI) by using the catch per unit effort (CPUE) and fishing effort to understand the variation of fishing ground. The fishing ground were also divided into different types and correlated with the SST isotherms in order to evaluate their forming mechanism. The results indicated that significant differences (P<0.01) were="" found="" for="" fgi="" with="" the="" fishing="" periods="" earlier="" mid="" stage="" and="" later="" areas="" north="" middle="" area="" south="" on="" basis="" of="" analysis="" variance.="" according="" to="" distribution="" we="" defined="" ground="" anchoveta="" as="" type="" ground.="" when="" warm="" sea="" surface="" waters="">20℃) had not intruded into the near shore area, the "A" type fishing ground occurred. Otherwise, the "B" type fishing ground occurred. Our findings suggested that the surface temperature structure with "A" type is favorable for the formation of fishing ground in the earlier or mid stage of fishing periods. Moreover, the 19℃ or 20℃ SST isotherm in earlier stage and the 18℃ or 19℃ SST isotherm in mid stage could be used as an indicator to search for the productive fishing ground.

Sponges of Porifera have powerful regeneration capacity. Among them, the genus Tethya is a special group, which has differentiation in cortex and choanoderm. In this paper, the morphology of Tethya sp., and its wound-healing process were studied by removing specific part of some tissues, to understand the transformation of Tethya sp. and the role of different tissues in the healing process. The results showed that the main transformation in the wound-healing process is the cell rearrangement resulted by the cell migration from the unwounded to the wounded part, the cortex and choanoderm are vital to the survival of Tethya; while the spicule center is less importance in the wound-healing process.

Resting cysts are largely formed during the red tide which may be the "seed bank" of next harmful algal bloom. And the resting cysts are resistant to normal physical and chemical treatments due to their thick cyst walls. In this paper, the resting cysts of Scrippsiella trochoidea were produced using N-limited medium. The resting cysts were inactivated using hydroxyl radicals based on a strong ionization discharge. The results showed that hydroxyl radicals could inactivate the resting cysts effectively when the CT value was 0.49 mg·min/L with a contact time of 10 s. Morphological changes were observed using scanning electron microscope which showed that hydroxyl radicals could destroy the thick cyst wall. After entering the cell, hydroxyl radicals may damage the chlorophyll and DNA. Also, the germination rate decreased to zero. In general, the ·OH treatment can be applied to inactivate the resting cysts of S.trochoidea and provide a new method to kill the harmful algal cysts in ballast water.

In order to explore the effect of Enteromorpha bloom on the bacterial community, Illumina MiSeq Sequencing was used to investigate the bacterial structure in source water, culture pond and drainage area in this study. The results showed that Gammaproteobacteria, Alphaproteobacteria, Actinobacteria, Bacteroidete and Deltaproteobacteria were the dominant bacteria groups in aquaculture water. Bacterial community in source water had higher in species numbers and Shannon diversity than pond and drainage area with Enteromorpha. Furthermore, pond and drainage area with Enteromorpha was dominated by heterotrophic bacteria in water (mainly Actinomycetales and Flavobacteriales), as well as by anaerobic bacteria in underlying sediment (mainly Desulfobacterales), which increased potential ability to produce hydrogen sulfide. Source water contained high abundance of conditional pathogenic microbe, such as vibrio and Piscirickettsiaceae; whereas little was detected in Enteromorpha-containing pond,which indicated that Enteromorpha had strong inhibitory effect on these pathogens. In addition, Enteromorpha also increased the abundance of Flavobacterium in pond and drainage areas; some genera of Flavobacterium are conditional pathogenic bacteria for aquaculture animal, and need pay attention to prevent such infections disease. Enteromorpha has the dual role to inhibit or increase abundance of different pathogens, and have importance effect to aquaculture. Overall, massive growth of Enteromorpha would produce the significant effect on the bacterial community, and have serious impact on the coastal environment. This study explored the novel findings of the microbial community relevant to Enteromorpha, and will provide guidance for the prevention and control of the green tide.

In order to verify the suitability of environmental satellite images being used to conduct concentration inversion of chlorophyll a (Chl a) in nearshore Ⅱ waters, and to obtain the inversion algorithm in the north nearshore water areas of Luanhe River, several inversion models of Chl a concentration were established based on the HJ-1A CCD2 images and synchronous measurement data. By comparing the simulated results with the validation data, the most prosperity model to simulate Chl a concentration for study area was selected. The results show that HJ-1A CCD2 images are effective enough to inverse the Chl a concentration of nearshore Ⅱ waters under the complex hydrological situation. We therefore built the reciprocal model by B3/B1 which was the optimal band combination for the study area. Inversion results show that the Chl a concentration gradually decreases from the nearshore to the inner sea, and the same is true from the north to the south, thus forming a high nutrient area to the sea outside the estuary. The maximum value of 25.0 μg/L occurs in the south of Jinshanzui, the minimum value of 4.6 μg/L in offshore areas occurs at about 13.2 km east of the Luanhe Delta, while the minimum value of 11.0 μg/L in nearshore areas occurs nearby the Luanhe Delta. The methods and processes analysis in this study can be used as references for the similar researches. In addition, this study can provide decision-making references for the local government to manage marine environment and formulate related policies, and the important supporting data for the sustainable development in this area.