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The force and response relation between the ocean and the atmosphere is critical for the development and diagnosis of the ocean and the atmosphere general circulation models(GCMs).Based on the relationship between sea surface heat flux anomalies and sea surface temperature anomalies(SSTA), the characteristics of intraseasonal air-sea interactions were analyzed over global oceans. The results show that the atmospheric forcing dominates in the subtropics. It is significant in the summer hemisphere, but not noticeable in the winter hemisphere. From the central to the eastern tropical Pacific Ocean and in the tropical Atlantic Ocean, SST forcing dominates throughout the year. Over the Indian Ocean, the performance of air-sea interaction differs with seasons. Along the coast of Somalia, over Arabian Sea, and over the Bay of Bengal, SST forcing dominates only from June to August. Instead, from September to November, atmospheric forcing takes the place of SST forcing and dominates over the Bay of Bengal. In the areas other than the above ones, the variability of SSTA or SSTA tendency has little connection with the surface heat flux, which suggests a decoupling between the ocean and the atmosphere in the intraseasonal band. Overall, the force and response relation between the ocean and the atmosphere in the intraseasonal band changes with seasons and locations. It can also differ from the ocean-atmosphere coupling in the seasonal time scale and longer time scales.

Using a simple conceptual coupled model, this study discussed the role of Westerly Wind Burst Event(WWB) on the two types of El Niño events(the Cold-Tongue El Niño type and the Warm-Pool El Niño type). The results indicate that WWB induced zonal advection and oceanic waves are very important to El Niño diversity. Since the model just includes fundamental oceanic and atmospheric processes and their interactions, our results provide the fundamental dynamical framework of El Nin~o diversity.

To research the current character, variation and pattern in vertical profile, current speed and direction were observed using ADCP at 3 fixed sites along the Zhejiang offshore in summer of 2006 and 2009. The results showed that: (1) In central and north of Zhejiang offshore (A and B sites), the current was rotating flow and it rotated in clockwise direction. In the south area(C site), the flood tidal current was north,while it was north by east in ebb period. In vertical profile, the current direction was unanimous. (2) The vertical average speed was similar in the three observation sites (44.4~51.1 cm/s), but significant difference presented in average speed of vertical profile. The biggest speeds in the three sites were all bigger than 110 cm/s, which all occurred in the flood period in spring tide. (3) During observation period, the average residual flow speed at A, B and C site was 21.9, 12.3 and 22.3 cm/s, respectively. Influenced by the Yangtze diluted water, at A and B sites the residual current directions in the upper layers were southwest. From the middle to the bottom layers the residual currents were veering in counter clockwise direction with the southeast direction in lower layers, which may be caused by the Taiwan Warm Current traction. At C site residual current flow was more consistent in vertical, which was mainly affected by the northeast monsoon.(4)In summer, along the Zhejiang offshore from south to north, the current direction turned to east gradually at central area (between B and C site).(5)During the low water discharge of Yangtze, the south costal current existed in the central and north of Zhejiang offshore. The current adjacent to Zhejiang was controlling by monsoon, the Yangtze diluted water and the Taiwan Warm Current together, but the role of them varied significant spatially.

Since Spartina alterniflora was transplanted on the Jiangsu coast in 1979, its rapid expansion has a great impact on the native coastal ecosystem. In Rudong, Fistulobalanus albicostatus provides a typical example of the influence by the expansion of Spartina alterniflora. In the present study, 28 quadrates along 5 tidal creeks were sampled during October 2012, to collect the above-ground parts of Spartina alterniflora plants and the barnacles attached to the plants. The maximum elevation at which barnacles attach to the plants were measured. Analyses of the samples reveal that the barnacles are distributed within a narrow zone, on average 5 m wide on both sides of the tidal creek; their landward extension is determined by the size of the tidal creek, i.e. a larger creek is associated with a longer extension. The maximum elevation at which barnacles attach to the plants shows the same level at different sites. Fistulobalanus albicostatus is the only barnacle species in the study area; its average biomass is 273±69 g·m^-2, and most barnacles have a diameter of 2~10 mm in the autumn. Biomass of Spartina alterniflora is 981±81 g·m^-2. Plants near the tidal creeks are tall and lower popularity density, while plants far away from the tidal creeks are undersized but higher popularity density. Correlation analysis indicates that although Spartina alterniflora provides the barnacles with an attachment base, its influence on the biomass and spatial distribution pattern is weak. The dominant factor of barnacle attachment-distribution is seawater inundation. The importance of the inundation time implies that the negative topography in relation to tidal creeks is beneficial to the attachment and survival of the barnacles. Meanwhile, higher velocity in tidal creek is advantageous for barnacle attachment, and flooding and ebbing tides in the creek will bring abundant food for barnacles.

The typical surface feature of Huanghe River estuary wetland is complex and diverse. In this study, a new classification model for coast wetland remote image was constructed using the linear spectral mixture analysis model, combined with normalized difference vegetation index(NDVI) and normalized difference water index(NDWI). Based on CHRIS hyperspectral image, a classification test of Huanghe River estuary wetland was carried, which consisted of 6 kinds of typical objects: phragmites, tamarix chinesis, suaeda, spartina, tidal flat and water, The results show that the overall accuracy of the combined model is 77.33%, and Kappa coefficient is 0.71, increasing 1.6% and 0.02 respectively compared with that from the classical MLC method, and especially, a better classification accuracy is obtained obviously for phragmites, suaeda, spartina and tidal flat.

Coastline changes are of great significance in studying ecological environment changes in coastal zones and even all over the globe. Through human-computer interactive interpretation for the TM images of 5 time phases, 1990, 1995, 2000, 2005 and 2010, we acquired the information about southern China continental coastline, and analyzed the features and reasons of the coastline changes. The results show that: (1) The length and fractal dimension of southern China continental coastline remain relatively stable, but there exists the evolutionary trend of overall shortening and partly lengthening of the coastline; (2) The coastline advances seaward in main parts of the coast and backs landward only in a few parts of the coast; (3) Analyses on two typical coasts, Changjiang River estuary-south bank of Hangzhou Bay and the Pearl River Delta show that the rate and intensity of spatial-temporal changes in southern China continental coastline are continuing to strengthen; (4) In the period from 1990 to 2010, the spatial-temporal changes in southern China continental coastline caused by the human factors are more significant than thoses caused by the natural factors, resulting in the increasing of the proportion of artificial coastline, and declining of the proportion of natural coastline.

There are many small-scale mountain rivers in Xiangshan Bay Basin, which flow from low mountains to the sea and form a relatively independent small watershed. In this study, the small-scale river features in the inner bay were quantitatively analyzed by the combined method of fluvial landform mathematical model and geographic information system technology. The results show that: (1)Dasong River is the longest and the most meandering river in Xiangshan Bay Basin, whose river fractal dimension value is generally small. (2)The river structures of Fuxi Stream and Dasong River are more complicated and well-developed than those of other rivers in Xiangshan Bay Basin. (3) Overall, apart from the some rivers (such as Yangong River and Qiancang River), other rivers show a trend of concave and stair-step shape. (4)The applications of S-A model has a certainty limitation. Fuxi Stream and Dasong River's bedrock riverbeds are in equilibrium in the S-A model.

Based on three TM images data of Cixi in the 2000, 2006 and 2013, landscape dynamic processes of the reclamation of Cixi during the past 13 years were analyzed. The results showed that: (1)There were significant differences in series time scale of landscape in reclamation region of Cixi. (2)The area of landscape in reclamation region tended to increase during the past 13 years, the most obvious change of which was aquaculture pond landscape. (3)The area within the inner landscape dynamically transformed into each other frequently, evidently showed that transformation of water, woodland , lawn and bare ground to architecture and aquacultural ponds. (4)Landscape shape became more complex during the past 13 years. Indices of landscape diversity and evenness decreased, suggesting that landscape fragmentation was aggravated.

During the Chinese DY20 and DY21 cruises, size-fractionated particulate biogenic silica (PBSi) and nutrients were analyzed for samples at 4 stations in the eastern and western Equatorial Pacific. It showed that the total PBSi concentrations at 4 stations were at a range of 5~65 nmol/ dm³ and its mean value in the eastern Equatorial Pacific was 46 nmol/dm³, which was about 3 times higher than that in the western Equatorial Pacific. PBSi concentrations with the size of 0.8~20 μm accounted for the major contributor of the total PBSi concentrations in the eastern Equatorial Pacific with an average contribution of 64%, while the contributions of two size classes of PBSi concentrations were equal in the western Equatorial Pacific. The results were that the distribution of nutrients had a prominent impact on the concentration and size composition of biogenic silica. And it might be an important factor in controlling the efficiency of biological pump in the Equatorial Ocean by controlling the composition structure of “silica pump”.

Based on multiple correlation equation about the tidal of Qiantangjiang River, upstream runoff and river water salinity index of Hangzhou reaches, an analysis was made about the effect of tidal bore in Qiantangjiang River on the water salinity of Hangzhou reaches. The findings suggest that the effect of lower reaches is more serious than that of upper reaches, and this effect increases when the tidal bore is getting stronger.

8 sections in islands of Wenling were investigated in October 2011 and April 2012 to assess impacts of disturbance on intertidal macrobenthos community structure. 96 species are identified, including 40 species of molluscs, 29 of macroalgae, 15 of carapaces, 6 of polychaetes, and 6 of echinoderms. The average biomass and abundance of macrobenthos are 1 794.16±1 148.08 g·m^-2and 679±497 ind·m^-2, respectively. The biomass and abundance in autumn are higher than those in spring. There is one main community structures in islands of Wenling, Tetraclita japonica-Thais clavigera. For all of the sections, T. japonica and T. clavigera are the dominant species and occupy over 80% of the whole biomass and abundance. According to hierarchical clustering analysis, MDS diagrams and ABC curve, macrobenthic community structure has suffered moderate disturbance with the consequence of poor stability in islands of Wenling. Compared to some neighbor islands (e.g. Dongtou, Nanji and Shengsi) in Zhejiang Province, the numbers of species are significantly less in islands of Wenling. Such distributional pattern of the habituating species in islands of Wenling appears to be closely attributed to the surrounding environment as well as to the impacts from anthropogenic activities (e.g. pollution, capturing, etc.), leading to the community structure degradation.

Net-phytoplankton community structure and abundance were preliminary studied on the basis of investigation in the northwest South China Sea from August to September, 2012. A total of 206 species were identified, belonging to 4 phyla with 55 genera, of which 55.3% were Bacillariophyta(40 genera and 114 species) and 41.7% were Pyrrophyta(10 genera and 86 species). The average cell abundance of phytoplankton was 66.67×10⁴cells·m^-3 , which was mainly contributed by diatom with mean value of 65.79×10⁴cells·m^-3. The mean value of dinoflagellates was only 0.88×10⁴cells·m^-3. The dominant species were diatom such as Thalassionema franenfeldii,Rhizosolenia alata and Thalassionema nizschioide. The average Shannon-Wiener diversity index of phytoplankton community was 2.67, and the high value occurred in the Xisha Islands and the east part of surveyed area. Distributive pattern of phytoplankton was much related with environmental condition. The water column with high phytoplankton abundance and species diversity often coincided with a high nutrient level particularly in upwelling zone. It suggests that nutrient may play important role in impacting the distribution of phytoplankton abundance and the community structure in this region.