| In this dissertation, spatial and temporal distributions of phytoplankton biomass and primary products in Chinese coastal area, and its environmental control mechanism are studied by combining the approaches of both on site measurement and modeling based on ocean remote sensing data. The seasonal and annual variations of chlorophyll and primary production in different sea areas are described, and the corresponding eco-dynamic process is discussed. In addition, the quantity of carbon fixed by phytoplankton in Chinese coastal area is estimated.Large-scale ecological zonation of the Yellow Sea (YS) and East China Sea (ECS) were studied through sorting out and analysis of chlorophyll a and primary production data for nearly 30 years. The studied sea areas were partitioned into several ecological zones by cluster analysis of correlative parameters of phytoplankton biomass and production. Distribution of biomass and production of phytoplankton exhibited obvious regional characteristics and seasonal variation; their border and levels in the ecological zones were closely related to water masses' properties, and the temporal and spatial variations.In it, the mutual growth and decline and mixing between the coastal water with high nutrient concentration and thin euphotic zone, and Kuroshio water with low nutrient concentration and thick euphotic zone were main factors governing the processes of a series of ecological variation.The research results also showed that although the partitioning results exhibited seasonal and spatial variations, three ecological zones, i.e. the Coastal Zone, Kuroshio Zone and East China Sea Shelf Zone were fundamental zones reflected pronouncedly by major temporal and spatial patterns of phytoplankton biomass and production in the Yellow Sea and East China Sea.In this paper, the distributions, size fractionations and environmental control mechanisms of phytoplankton stock and primary production (PP) in the northern South China Sea were studies based on a comprehensive survey conducted in February 2004 in this area.The results show that the average concentrations of chlorophyll a (Chla) is 0.6 mg/m3 and PP is 386 mgC/m2/d.The distributions and size fractionations of Chla and PP in the northern South China Sea (NSCS) are mainly controlled by the nutrients which driven by monsoon-circulation and there are obvious coupled physical-chemical-biological processes in this area.In detail, in the coastal zone, influenced by the coastal current and Zhujiang dilute water, the characteristics are low temperature, low salinity, rich nutrients, high Chla and PP. While in the deep sea, the distributions of nutrients and Chla are mainly controlled by the mesoscale eddies:high temperature, low salinity, poor nutrients, low Chla and PP appear when controlled by the anticyclonic eddies and the characteristics are on the contrary when controlled by cyclonic eddies. With respect to the size fractionations of phytoplankton, Net>Nano>Pico are observed in the coastal zone, while Pico>Nano>Net in deep sea. The contributions of Net, Nano and Pico for Chla and PP are 24.16%,30.36%,45.48% and 11.81%,25.35%, 61.84%, respectively in the whole study area.In this study, an enhanced primary production estimation model (C-VGPM), which is more suitable for Chinese costal area, has been established based on comparing mainstream international primary production estimation models and analyzing the characteristics of phytoplankton community in Bohai Sea, Yellow Sea and East China Sea. The model parameters are calculated from remote sensing products, such as Chl a,K490 and PAR et al.,provided by the satellite SeaWiFS.By using the C-VGPM model and appropriate model parameters, the distributions of chlorophyll and primary production in ten years, from 1998 to 2007, are estimated.The results show that the seasonal distribution of primary production in the studied sea area is a single peak. The primary production in summer is the highest, i.e.,PP in summer (524 mgC/m2/d)>PP in spring (424 mgC/m2/d)> PP in autumn (346 mgC/m2/d)> PP in winter(177 mgC/m2/d). In terms of spatial distribution, PP in Yellow Sea is the highest (404 mgC/m2/d), the middle is in the East China Sea(372 mgC/m2/d), the lowest is in Bohai Sea (289mgC/m2/d).The average primary production in the whole studied sea area is 368 mgC/m2/d.The highest phytoplankton biomass and primary production in China Sea appears in shelf and estuary area, while those in the costal area and off-shelf area are comparatively lower. The spatial and temporal distributions of inshore chlorophyll and primary production are described in detail in this study. It is observed that from an overall point of view, the climate, the water mass and the terrestrial input in China Sea control the quantity and distribution of phytoplankton biomass and primary production together. An improved VGPM model were developed and applied to estimate the primary production in the northern South China Sea. The parameters of the model were gained based on the remote sensing data(including Chl a,K490 and SST et al.)provided by SeaWiFS and AVHRR.The model was modified according to the synchronous ship-measured data and the errors were estimated as well.Based on this improved model, the monthly mean of primary production in 7 years(1998 to 2004) in the northern South China Sea were calculated.Results show that the primary production in the studied area gradually decrease from coastal zone (the mean >400 mgC·m-2·d-1) to deep sea (100～200 mgC·m-2·d-1).With respect to the seasonal variation, the daily average primary production in the whole study area is the highest in winter (608 mgC·m-2·d-1) and the lowest in summer (292 mgC·m-2·d-1) and it is almost the same between spring and autumn.The main factors which affect the spatial-temporal distribution of primary production are nutrients, temperature and PAR.,particularly nutrients which driven by monsoon-circulation.Based on the improved VGPM model and 7 years average data from SeaWiFS and AVHRR, the annual variation of surface chlorophyll a and primary production in different environments (e.g. Estuary,upwelling and eddies) in the northern South China Sea was analyzed in this study. The results show that the physical-chemical-biological coupling processes driven by monsoon are the main factor controlling the spatial-temporal variation of phytoplankton biomass and primary production. With the changes of physical features (e.g. monsoon, circulation and eddies), chlorophyll a and primary production show great variation.The high values appeared in the Peal River Estuary and coastal zone and the low ones appeared in the shelf anti-cyclonic eddies and the open sea. According to their temporal change,in most cases, the phytoplankton biomass and primary production are high when the Northeast Monsoon prevails and low when the Southwest Monsoon does. Finally, based on the remote sensing data, the annual quantity of fixing carbon in the northern South China Sea was estimated (4.83×107t C/a) and the contributions of the coastal zone,shelf and open sea are 38%,29% and 33%,respectively.
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