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Based on the method of the controlling factors analyses, a satellite remote sensing algorithm was developed to retrieve the aquatic pCO₂ in the Pearl River Estuary in summer time. The end members of the Pearl River water and Kuroshio water were applied to quantify the pCO₂ variations controlled by the water mass mixing and thermal dynamic effects, and a look-up table was generated to fulfill the calculation. Moreover, relationship between the a_CDM(443 nm) and surface layer water salinity was established to retrieve the salinity from ocean color satellite data. In addition, based on the underway measured pCO₂ and matchup satellite Chl-a data, the model for the biological effect on the pCO₂ was developed. Finally, the mixing and biological effects on the pCO₂ were combined to retrieve the pCO₂ from the satellite. Based on the established model, the comparisons between the retrieved pCO₂ and underway measured pCO₂ were carried out. The results show that if only considering the mixing and thermal dynamic effects it would overestimate the pCO₂, while if considering the biological effect additionally it would much improve the results not only on the magnitudes, but also the variations. The satellite-retrieved pCO₂ also reveals that in summer time, the coastal region in the Pearl River Estuary is a sink of the atmosphere CO₂, while the outer shelf is a weak source of CO₂.

A 3D temperature-salt numerical model of the sea area near Jinjiang was established,based on MIKE3, horizontal and vertical diffusion in different tide was simulated. The results show that brine distribution is affected by water level and current velocity,the higher the water level and velocity,the greater the effect of dilution and diffusion,and the smaller the vertical diffusion. The brine discharge from 200 000 t/d seawater desalination plant,the range of salt-rise is about hundreds of meters in horizontal and about 3 m in vertical. With the increasing of water level and current velocity,the salt-rise is spreading quickly. If there is no sensitive area nearby,it will not have a significant impact on the marine environment.

The sun glitter is caused by the direct reflection of the sun light from the rough sea surface, and its intensity is strongly affected by the sea surface roughness. The sea surface roughness is mainly affected by the sea surface wind field. Therefore, the remote sensing images containing sun glitter information are of great significance in ocean dynamic processes detection and sea surface wind speed estimation. In this study, 25 remote sensing images of MISR(Multi-angle Imaging Spectro Radiometer)sensor equipped with Terra Satellite acquired from February 2016 to March 2017 were used. The zenith angle, azimuth angle and sensor angles from the MISR images were obtained, then the normalized radiation intensities of sun glitter were corrected, while the sea surface roughness were further acquired, and the sea surface wind speed was estimated. Finally, the estimation results were compared to the model wind speed data of ECMWF(European Centre for Medium-Range Weather Forecasts).The results show that the correlation coefficients (0.745) are high, and the root mean square error and the mean absolute deviation error are 1.514 m·s^-1 and 1.319 m·s^-1, respectively. The preliminary experimental results show that it is feasible to extract the sea surface wind speed by using MISR multi-angle optical remote sensing images.

The influence of sediment turbidity on chlorophyll sensor determination of in vivo chlorophyll fluorescence was studied. The results show that turbidity can cause fluorescence effect and light shielding effect on the determination of chlorophyll fluorescence. In the range of 100 NTU turbidity, the fluorescence value of chlorophyll shows a good linear relationship with the turbidity of sediment suspension, which increases with the increase of turbidity. When actually measuring the in vivo chlorophyll fluorescence of diatoms in water, turbidity of sediment suspension causes light shielding effect that decreases in vivo chlorophyll fluorescence as turbidity increases. The concentration of microalgae in the water is higher, the light shielding effect is stronger. In 1 000 mV (including 10 μg/L), the highest concentration of microalgae, sediment suspension can reduce the chlorophyll fluorescence value by 20% at 100 NTU turbidity. Based on the experimental data, a correction method of turbidity effect of in vivo chlorophyll fluorescence detection is proposed. Within 100 NTU turbidity, the corrected deviation of chlorophyll fluorescence values is reduced to less than ±10% and the corrected fluorescence value is close to the true chlorophyll fluorescence.

Monitoring and recognizing the dynamic changes of coastline are vital for the protection of coastal zones and the rational exploitation of coastal resources. In this study, Canny edge detector was used to extract the coastline data of the Hainan Island in 1990, 2000, 2010 and 2015 from the data source of Landsat TM/OLI images. Then, the changes of coastline length and land area were obtained to analyze the characteristics of temporal and spatial variations regarding the coastline of the Hainan Island over the past 25 years. The results show that the total length of the island's coastline had increased by 33.58 km from 1990 to 2015, with the coastline expanding outwards and the offshore area increasing in size. The changes mainly happened in the north and the east coasts where the artificial coastline had evidently increased and natural coastline such as muddy coastline diminished. Largely affected by human factors, the coastal development was diversified in patterns, with pond farming, construction of cities and towns, ports and piers as the main forms.

The speckle noise of high resolution airborne MiniSAR image is serious, and in image the edge of the reclamation is fuzzy and messy. For more efficient extraction of reclamation information, a method of watershed segmentation was presented based on texture feature for SAR image of reclamation. First, the airborne MiniSAR image was filtered by the gray level co-occurrence matrix, and the texture feature image was obtained. Then the watershed algorithm was used to segment the texture feature image and to get the morphological reconstruction image, and finally, the threshold method was used to segment the morphological image, and to get the final results of the two values. On the one hand, this method suppresses the influence of speckle noise by adjusting the gray co-occurrence matrix texture filtering window size . On the other hand, it uses watershed algorithm of fuzzy edge clutter images to improve the accuracy of information extraction of sea reclamation. Test results show that this method is effective for the image segmentation of high resolution SAR image.

The spectral absorption characteristics of vegetation are not only closely related to the growth of vegetation, but also affected by soil moisture and other factors. In this study , Phragmites australis, Spartina anglica and Scirpus mariqueter were taken as the research objects, which are the typical vegetation in Nanhui Wetland of Yangtze River Estuary. Based on the calculation of spectral characteristic parameters, their spectrum of absorption and deformation of PSDI values were analyzed. Finally, combining with the measured soil moisture, the correlation between PSDI values of three kinds of vegetation and soil moisture values were analyzed. The results show that the PSDI value of Spartina anglica is maximum, the PSDI value of Scirpus mariqueter is minimum, and that of Phragmites australis is somewhere in between. It indicates that Spartina anglica is most affected by environment. The correlation between PSDI of Spartina anglica and soil moisture is maximum, the correlation between PSDI of Phragmites australis and soil moisture is minimum, while that of Scirpus mariqueter is somewhere in between.This points that Spartina anglica has stronger adaptability to wetland environment.

The geochemical characteristics and spatial distribution characteristics of 7 heavy metal elements in the surface sediments from the offshore area of eastern Sanya were studied, and the degree of pollution was assessed by using the index of geoaccumulation and the Nemerow comprehensive index methods. It is found that the content of heavy metals in the surface sediments from the offshore area of eastern Sanya are lower than the average value of elemental content in the neritic sediments of China,and the content of heavy metals conforms to the standard of Marine Sediment QualityⅠ, and the spatial distribution of the most heavy metal elements approximately follows the elemental particle-size control law. The provenances of heavy metals in this area are mainly from the terrigenous fine-grained sediments. The results of the index of geoaccumulation and the Nemerow comprehensive index methods all indicate that the heavy metals in the surface sediments of the study area are below pollution level and belong clean condition, the environment of surface sediments is fine.

Surface sediment samples were collected from Sanmen Bay in Zhejiang Province. The distribution of total concentration of five heavy metals (Zinc, Chromium, Cadmium, Copper, and Lead) was determined, and their speciation was investigated using BCR extraction method. The pollution level and ecological hazard of these heavy metals were evaluated with three methods: Potential Ecological Risk Index (Eⁱ_r), Risk Assessment Code (RAC), Ratio of Secondary and Primary Phase (RSP). The distribution of five metals show that the total concentrations in inner bay are higher than those out of the bay. The results of metal speciation in surface sediment show that the residual fraction of four metals are predominated except for Pb, of which Zn accounts for 79.20%~84.25%, Cr accounts for 93.24%~96.16%, Cd accounts for 34.71%~57.58%, and Cu accounts for 66.06%~79.51%, respectively. The dominated fraction of Pb is the part bounded to amorphous Fe and Mn oxides and hydroxides, which accounts for 56.58%~76.44%. The evaluation results indicate that Cd is the primary element in the area according to Potential Ecological Risk Index, and which is consistent with that by the Risk Assessment Code method. However, Pb is evaluated to be the primary element with potential ecological threat according to the Ratio of Secondary and Primary Phase, and followed by Cd.

In order to meet the expanding applications of side-scan sonar and improvement of more users' requirement, some hydrography standards were published by International Hydrographic Organization and the world's developed countries one after another. For the purposes of improvement of Chinese specifications for side-scan sonar survey, the comparison of system detection capability, survey lines plan, data acquisition requirements, quality control and other measurements were studied in detail. And the problems and weakness of Chinese specifications for side-scan sonar survey were analyzed.It points out the weakness of China's specifications for side scan sonar in the measurement line layout, data acquisition requirements, etc., in order to promote the realization of China's measurement standards as soon as possible with international standards.

In order to investigate the effects of natural additive on Plectropomus Leopardus, 4 kinds of different contents of natural products (astaxanthin, xanthophyll, spirulina and corn gluten meal ) were selected to formulate the baits to feed the leopard coral grouper (Plectropomus leopardus) in a recirculating aquaculture system for seventy-five days. The main growth index and the L^* value (Lightness), a^* value (red—green) and b^* value (yellow—blue) of body color in these fish's eight parts (head cheek, opercula, dorsal, abdomen, dorsal fin, pectoral fin, tail fin and caudal peduncle) were measured by scale, straightedge and colorimeter before and after the experiment. The results show that compared with control group, these four additives have no significant impact on the weight gain rate, specific growth rate, feed coefficient of leopard coral grouper (P<0.05); all of these additives make the L^* value slightly smaller, and there are significance occurrings on some parts. Compared with the control group, all of the additives significantly lift the a^* value and b^* value of leopard coral grouper, among which the experimental feed with astaxanthin has the most significant effect.

In this study, residues, possible sources and ecological risk of 22 polychlorinated biphenyls (PCBs) in five mollusks from Zhoushan Fishing Ground (ZFG) were studied. The total concentration of PCBs in the collected samples ranged from 18.0 ng/g dry weight (dw) to 95.9 ng/g dw, with average of 51.9 ng/g dw. Compared with mollusks from other sea areas, the levels of PCBs in ZFG were at the median worldwide. The results of composition profiles show that penta- and di-PCBs are the most abundant. The health risk of PCBs calculated was far below 1, indicating low risk to human health.