A model study on carbon cycle and phytoplankton dynamical processes in the Bohai Sea

The carbon cycle of lower trophic level in the Bohai Sea is studied with a three-dimensional biological and physical coupled model. The influences of the processes (including horizontal advection, river nutrient load, active transport etc. ) on the phytoplankton biomass and its evolution are estimated. The Bohai Sea is a weak sink of the CO2 in the atmosphere. During the cycle, 13.7% of the gross production of the phytoplankton enter the higher trophic level and 76.8 % of it are consumed by the respiration itself. The nutrient reproduction comes mainly from the internal biogeochemical loop and the rem-ineralization is an important mechanism of the nutrient transfer from organic form to inorganic. Horizontal advection decreases the total biomass and the eutrophication in some sea areas. Change in the nutrient load of a river can only adjust the local system near its estuary. Controlling the input of the nutrient, which limits the alga growth, can be very useful in lessening the phytoplankton biomass.     

Tropical Atlantic variability in a coupled physical–biogeochemical ocean model

A three-dimensional ocean biogeochemical model of the tropical Atlantic Ocean was run for more than half a century (1949–2000) in order to characterize the ocean biogeochemical response to variable forcing over this period. The seasonal cycle in the equatorial upwelling zone agrees reasonably well with observations and other published simulations but underestimates phytoplankton biomass under strong upwelling conditions. Away from the equator, modelled nutrient flux and biological production are maximal in each hemisphere's winter season, and appear to be proximately forced by evaporative cooling and wind stirring rather than by Ekman upwelling. The fraction of the total variance associated with the seasonal cycle is considerably smaller for modelled biogeochemical fields than for sea-surface temperature over this long simulation, and much of the biogeochemical variance is associated with interdecadal changes. The model results suggest that the tropical Atlantic became more productive following the Pacific climate shift of 1976 and remained so until about 1989. Summer surface nitrate concentrations during the 1990s were lower than those in the 1980s. The relationship between the equatorial and off-equatorial regimes may have changed following the 1976 event, with equatorial variability dominating the basin-wide variance patterns after 1976.     

南黄海浮游植物季节性变化的数值模拟与影响因子分析

用三维物理-生物耦合模式研究南黄海浮游植物(以叶绿素a为指标)的季节变化.对于物理模式采用Princeton ocean model(POM),对于生物模式考虑溶解无机营养盐(氮、磷、硅)、浮游植物、食草性浮游动物和碎屑.给定已知的初始场和外加边界强迫,模拟了观测到叶绿素a的主要时、空分布特征,如浮游植物的春、秋季水华和夏季次表层叶绿素a极大值现象等.研究表明,浮游植物春季水华最先发生于黄海中央海域,主要原因是该海域透明度较高,流速较小.春季水华开始于垂直对流减弱和层化开始形成之前(约3月底至4月上旬),显著地依赖水层的稳定性.水体层化以后(约5～9月)叶绿素a浓度高值区分布在南黄海的南部和锋区.夏季的南黄海中央海域,由于上混合层营养盐几乎耗尽,限制了浮游植物的生长,在紧贴温跃层下部的真光层,具有丰富的营养盐和合适的光照,次表层叶绿素a极大值得以形成.秋季(约9～11月份,略迟于海表面开始降温的时间,随地点不同而异)随垂直混合的增强,有利于营养盐向上输运,浮游植物出现一次较小的峰值.     

Hydrological and biogeochemical features of the Northern Adriatic Sea in the period 2003–2006

This paper reports on the main biogeochemical properties of the Northern Adriatic Sea in the period May 2003–November 2006 within the framework of the European program INTERREG III Italy‐Slovenia. Spatial and temporal distributions of water density, dissolved oxygen, nutrients (nitrogen, phosphorous and silicon) and chlorophyll a are presented. Multivariate methods such as fuzzy k‐means, self‐organising maps and cluster analysis were used to identify the different water masses and to characterise the temporal and spatial variability of the main biogeochemical features present in the area. The results confirm that the Po River outflows and the meteorological forcing factors are the main components triggering the alternation of stratification and mixing of the water column and that strongly affect the trophic state of the basin. In general, oligotrophic conditions dominate, and were more pronounced offshore, but mesotrophy occurred episodically in May 2004 and July 2005, when phytoplankton blooms were observed concomitant with vertical stability of the water column. A marked interannual variability was also observed, supporting the importance of maintaining long‐term observations of the basin.     

Downscaling biogeochemistry in the Benguela eastern boundary current

Dynamical downscaling is developed to better predict the regional impact of global changes in the framework of scenarios. As an intermediary step towards this objective we used the Regional Ocean Modeling System (ROMS) to downscale a low resolution coupled atmosphere–ocean global circulation model (AOGCM; IPSL-CM4) for simulating the recent-past dynamics and biogeochemistry of the Benguela eastern boundary current. Both physical and biogeochemical improvements are discussed over the present climate scenario (1980–1999) under the light of downscaling.Despite biases introduced through boundary conditions (atmospheric and oceanic), the physical and biogeochemical processes in the Benguela Upwelling System (BUS) have been improved by the ROMS model, relative to the IPSL-CM4 simulation. Nevertheless, using coarse-resolution AOGCM daily atmospheric forcing interpolated on ROMS grids resulted in a shifted SST seasonality in the southern BUS, a deterioration of the northern Benguela region and a very shallow mixed layer depth over the whole regional domain. We then investigated the effect of wind downscaling on ROMS solution. Together with a finer resolution of dynamical processes and of bathymetric features (continental shelf and Walvis Ridge), wind downscaling allowed correction of the seasonality, the mixed layer depth, and provided a better circulation over the domain and substantial modifications of subsurface biogeochemical properties. It has also changed the structure of the lower trophic levels by shifting large offshore areas from autotrophic to heterotrophic regimes with potential important consequences on ecosystem functioning. The regional downscaling also improved the phytoplankton distribution and the southward extension of low oxygen waters in the Northern Benguela. It allowed simulating low oxygen events in the northern BUS and highlighted a potential upscaling effect related to the nitrogen irrigation from the productive BUS towards the tropical/subtropical South Atlantic basin. This study shows that forcing a downscaled ocean model with higher resolution winds than those issued from an AOGCM, results in improved representation of physical and biogeochemical processes.     

Study of long-term variations in the Black Sea fields using an interdisciplinary physical and biogeochemical model

Using an interdisciplinary three-dimensional physical and biogeochemical model developed for the Black Sea, the long-term evolution of marine dynamics and ecosystem is investigated. The hydrophysical fields were calculated from a model of Black Sea circulation with assimilation of hydrographic survey and satellite measurement data from 1971 to 2001. The circulation model reproduces well processes of various scales in both space and time (particularly the seasonal course and interannual variability of main hydrophysical fields). The resulting flow fields are then used to calculate the long-term evolution of the components of the lower level of the food chain in the Black Sea ecosystem. The biogeochemical model used in the calculations is based on the nitrogen cycle and includes a parameterization of the main biological and chemical interactions and processes in the upper layer of the Black Sea. The numerical experiments indicated that the biogeochemical component of the model rather successfully reproduces the main features and evolution trends in the Black Sea ecosystem for the period under consideration: the growth in the phytoplankton biomass during eutrophication and changes in seasonal cycles of the main ecosystem components. Also, the hydrophysical processes were shown to be important for a reliable reproduction of long-term changes in the ecosystem.     

我国近海陆架锋面与生态效应研究回顾

海洋锋面存在于特征明显不同的2种或多种水系或水团交界处,锋面区域形成的次生环流和辐聚作用可显著影响到海洋中的物质输运与生物生产,故受到海洋学家的广泛关注。研究发现,我国近海陆架存在14个永久性的准静止锋面（渤海海峡锋面、山东半岛沿岸锋面、苏北沿岸锋面、西韩湾锋面、京畿湾锋面、济州岛西锋面、长江环形浅滩锋面、闽浙沿岸锋面、黑潮锋面、台湾沿岸锋面、闽粤沿岸锋面、珠江口沿岸锋面、琼东锋面和北部湾锋面）,且部分海域观测到双锋面、穿刺锋面和锋面波等现象。它们与陆架环流及其他动力过程（如：涡旋、内波等）共同控制着我国边缘海的物质能量输运与交换以及生物生产力格局。近岸物质沿锋面、跨锋面输运与锋区的垂向输送过程对我国边缘海生物地球化学循环和生态过程存在显著季节性影响。冬季到春季,沿岸锋面松弛能够加强物质从近岸向陆架的输运,进而在空间上调制春季藻华暴发的时间与量级;夏季到秋季,我国边缘海存在显著的潮汐锋面系统,锋面的辐聚效应以及次级环流可显著提高锋面区域的营养盐浓度和改善光照水平,对浮游植物的生长聚集起到促进作用,故在富营养化的河口与沿岸海域,锋面区域容易成为赤潮或缺氧高发区。此外,锋面的物理屏障作用使得两侧水团保持相对独立的物理与化学特征,因而在我国边缘海生境区划和生物多样性梯度变化等方面扮演重要角色,这些研究对认识我国边缘海物质循环与生物生产的控制机制具有重要作用。未来仍需充分结合观测与卫星资料,运用多过程耦合的高分辨率模型,深入认识锋面的精细结构与动态变化,加强亚中尺度和小尺度过程及其生态效应的研究。     

基于遥感数据分析南海叶绿素与颗粒物的季节变化与相互关系

本文基于卫星遥感的叶绿素a浓度与颗粒物后向散射系数月平均数据以及其他海洋与气象参数,详细分析了两个生物光学参量在季节尺度上的相关性及其与物理参数的耦合关系,并运用光驯化模型分析了南海表层水体浮游植物的生理学季节变化特征。结果表明,受南海地形和风场等物理参量的变化,南海叶绿素a浓度与颗粒物后向散射系数存在显著的季节和空间分布特征,具有一定的共变性和差异性。在南海近岸及浅水区,叶绿素a浓度与颗粒物后向散射系数有很好的耦合关系;而在南海深水海盆区,叶绿素a浓度冬高夏低,其季节循环过程与颗粒物后向散射系数相反,这主要是受浮游植物生理学过程的影响。"生物量控制区"与"光驯化控制区"的分界在南海与陆架-海盆分界线一致,体现了水深条件对浮游植物生理状态的影响。此外本文还发现,在吕宋海峡西部海区,叶绿素a与颗粒物后向散射系数的关系表现出"生物量-光驯化共同控制"的特点。     

夏季南海北部浮游植物对上升流与羽状流的响应

文章建立了基于真实场驱动的三维物理—生态耦合模型, 利用模型定量分析了夏季南海北部上升流和羽状流过程对浮游植物生物量空间分布的影响程度及作用机制。首先, 利用2006—2008年卫星遥感数据及2006与2008年夏季观测数据对模型进行了验证, 结果表明, 模型能较好地再现夏季南海北部上升流和羽状流过程, 较好地反映出浮游植物的空间分布特征。模拟分析结果显示, 夏季南海北部浮游植物主要分布在50m等深线以内。琼州海峡东部海域和汕头海域浮游植物垂向分布较为均匀, 上升流的贡献均达到90%以上, 表层水平平流输送是浮游植物主要的汇, 生物过程是浮游植物的源。珠江口和汕尾海域浮游植物存在表层和次表层两个高值区, 羽状流贡献35%~40%, 主要促进表层浮游植物生长, 而上升流贡献60%~65%, 主要促进中底层浮游植物的生长。粤西海域上升流对浮游植物的贡献占92%, 主要促进中底层浮游植物生长, 而表层浮游植物浓度极低。整体上, 夏季南海北部上升流和羽状流主要是通过输送营养盐的方式影响浮游植物的生长。上升流对营养盐的输送作用是向岸方向的爬升输送和平行于等深线的沿岸流输送共同作用的结果。跃层的存在改变了营养盐的垂向输送过程, 是导致上升流和羽状流过程对不同水层浮游植物贡献差异的关键因素之一。整体而言, 夏季南海北部浮游植物空间分布差异是以上升流、羽状流主导, 环流—营养盐—生物过程共同作用的结果。     

Factors controlling trophic conditions in the North-West Adriatic basin: Seasonal variability

The North-Adriatic basin shows typical shallow water mass characteristics which in a first approach, can be considered independent of the Middle and the Southern basins, being more affected by seasonal temperature and salinity variability. Primary production estimates represent the main quantitative assessments of the trophic conditions of a marine system, resulting from the combined effect of a large number of oceanographic factors. In this paper the results from three EUROMARGE AS (EEC-MAST II-MTP project) field trips carried out in 1994 are presented as a contribution to the better understanding of the factors controlling the trophic balance in the Northern Adriatic basin. These results include: depth profiles of salinity, nutrients and chlorophyll a concentrations, oxygen saturation, phytoplankton taxonomy and abundance, estimated biomass and primary production measurements by the ¹⁴C in-situ incubation method. The field trips were carried out in three seasons (February, July, September 1994) and the results reported belong to three stations in the northern basin, 5 miles off Ravenna, Cesenatico and Ancona, respectively. As expected, the physical situation of the water column was different in the three periods: the water was mixed in February and stratified in July and September. Nutrient concentrations were higher in winter, whilst the maximum of primary production was measured in September. The phytoplankton was composed predominantly of diatoms. The correlations between primary production and salinity reflect a difference in the factors controlling primary production. During February and September nutrients coming from rivers play an important role, although with a decreasing influence from station 1, nearest to the Po delta, towards station 3. Depth profiles of nutrient concentrations and O₂ saturation measured during summer in the water column suggest that regeneration of nutrients in the water column down to the bottom boundary layer must play an important role in the nutrient cycling and dynamics in the basin.     

Biogeochemical patterns in the Atlantic Inflow through the Strait of Gibraltar

The effects of tidal forcing on the biogeochemical patterns of surface water masses flowing through the Strait of Gibraltar are studied by monitoring the Atlantic Inflow (AI) during both spring and neap tides. Three main phenomena are defined depending on the strength of the outflowing phase predicted over the Camarinal Sill: non-wave events (a very frequent phenomenon during the whole year); type I Internal wave events (a very energetic event, occurring during spring tides); and type II Internal wave events (less intense, occurring during neap tides).During neap tides, a non-wave event comprising oligotrophic open-ocean water from the Gulf of Cádiz is the most frequent and clearly dominant flow through the Strait. In this tidal condition, the inflow of North Atlantic Central Water (NACW) provides the main nutrient input to the surface layer of the Alboran Sea, supplying almost 70% of total annual nitrate transport to the Mediterranean basin. A low percentage of active and large phytoplankton cells and low average concentrations of chlorophyll (0.3–0.4 mg m⁻³) are found in this tidal phase. Around 50% of total annual phytoplankton biomass transport into the Mediterranean Sea through the Strait presents these oligotrophic characteristics.In contrast, during spring tides, patches of water with high chlorophyll levels (0.7–1 mg m⁻³) arrive intermittently, and these are recorded concurrently with the passage of internal waves coming from the Camarinal Sill (type I internal wave events). When large internal waves are arrested over the Camarinal Sill this implies strong interfacial mixing and the probable concurrent injection of coastal waters into the main channel of the Strait. These processes result in a mixed water column in the AI and can account for around 30% of total annual nitrate transport into the Mediterranean basin. Associated with type I internal wave events there is a regular inflow of large and active phytoplankton cells, transported in waters with relatively high nutrient concentrations, which constitutes a significant supply of planktonic resources to the pelagic ecosystem of the Alboran Sea (almost 30% of total annual phytoplankton biomass transport).     

Decadal-Scale Climate and Ecosystem Interactions in the North Pacific Ocean

Decadal-scale climate variations in the Pacific Ocean wield a strong influence on the oceanic ecosystem. Two dominant patterns of large-scale SST variability and one dominant pattern of large-scale thermocline variability can be explained as a forced oceanic response to large-scale changes in the Aleutian Low. The physical mechanisms that generate this decadal variability are still unclear, but stochastic atmospheric forcing of the ocean combined with atmospheric teleconnections from the tropics to the midlatitudes and some weak ocean-atmosphere feedbacks processes are the most plausible explanation. These observed physical variations organize the oceanic ecosystem response through large-scale basin-wide forcings that exert distinct local influences through many different processes. The regional ecosystem impacts of these local processes are discussed for the Tropical Pacific, the Central North Pacific, the Kuroshio-Oyashio Extension, the Bering Sea, the Gulf of Alaska, and the California Current System regions in the context of the observed decadal climate variability. The physical ocean-atmosphere system and the oceanic ecosystem interact through many different processes. These include physical forcing of the ecosystem by changes in solar fluxes, ocean temperature, horizontal current advection, vertical mixing and upwelling, freshwater fluxes, and sea ice. These also include oceanic ecosystem forcing of the climate by attenuation of solar energy by phytoplankton absorption and atmospheric aerosol production by phytoplankton DMS fluxes. A more complete understanding of the complicated feedback processes controlling decadal variability, ocean ecosystems, and biogeochemical cycling requires a concerted and organized long-term observational and modeling effort. This revised version was published online in July 2006 with corrections to the Cover Date.     

Physical oceanographic conditions around the S1 mooring site

We describe physical oceanographic conditions around the S1 biogeochemical mooring site (30°N, 145°E) between February 2010 and July 2013. At the S1 mooring site, there is a clear seasonal variability of the mixed layer depth, wind forcing as well as horizontal kinetic energy in a near-inertial band. Interannual variability of the winter mixed layer was observed. The winter mixed layer depth was shallower in early 2010 and became deeper afterwards. Several mesoscale eddies and typhoons passed by the S1 mooring sites every year. Based on observed events, we suggest that those physical processes possibly affected biogeochemical properties around the S1 mooring site.     

大亚湾浮游植物粒级结构对温排水和营养盐输入的响应*

大亚湾核电站温排水对其邻近海域的生态效应日益突出。文章结合现场调查和室内模拟实验, 研究了夏季和冬季大亚湾海域沿温排水温度梯度的浮游植物粒径结构特征, 探讨了营养物质的输入可能对其产生的影响, 以期深入了解浮游植物对升温以及富营养化作用的响应机制。结果表明, 适温条件对浮游植物的生长起促进作用, 在极高温(36.0℃)环境下则产生抑制作用, 在排水口邻近高温区夏季和冬季浮游植物叶绿素a含量均呈较低分布。交互模拟实验发现不同季节浮游植物对于温度和营养盐的敏感性存在差异, 夏季营养盐对浮游植物生长的促进作用比温度明显, 冬季温度的作用则更为显著。现场观测和模拟实验均显示, 水温升高和营养盐加富均可造成小粒级浮游植物 (<20μm)所占比例的增加; 因此, 升温和营养盐输入均可能导致浮游植物粒级结构呈小型化趋势, 并对食物网能量流动与物质循环、生态系统的结构稳定性以及海洋渔业的产量造成潜在影响。     

Study the Mechanism of Surface Chlorophyll–a Variability in the Southern Tropical Indian Ocean Using an OGCM

Eleven years (1997–2007) of SeaWiFS observations and Ocean General Circulation Model sensitivity experiments are used to understand chlorophyll–a variability in the southern tropical Indian Ocean. The strong offshore Ekman transport forced by anomalous southeasterly winds are responsible for inducing higher chlorophyll-a in the eastern equatorial Indian Ocean. In the case of the southwest tropical Indian Ocean, Rossby waves and local upwelling are responsible for lifting the phytoplankton from deep chlorophyll maxima to the surface. Both intraseasonal dynamical response and interannual forcing are responsible for the phytoplankton blooming in the western basin, whereas the interannual forcing is mainly responsible in the east.     

Monsoon-driven biogeochemical processes in the Arabian Sea

Although it is nominally a tropical locale, the semiannual wind reversals associated with the Monsoon system of the Arabian Sea result annually in two distinct periods of elevated biological activity. While in both cases monsoonal forcing drives surface layer nutrient enrichment that supports increased rates of primary productivity, fundamentally different entrainment mechanisms are operating in summer (Southwest) and winter (Northeast) Monsoons. Moreover, the intervening intermonsoon periods, during which the region relaxes toward oligotrophic conditions more typical of tropical environments, provide a stark contrast to the dynamic biogeochemical activity of the monsoons. The resulting spatial and temporal variability is great and provides a significant challenge for ship-based surveys attempting to characterize the physical and biogeochemical environments of the region. This was especially true for expeditions in the pre-satellite era.Here, we present an overview of the dynamical response to seasonal monsoonal forcing and the characteristics of the physical environment that fundamentally drive regional biogeochemical variability. We then review past observations of the biological distributions that provided our initial insights into the pelagic system of the Arabian Sea. These evolved through the 1980s as additional methodologies, in particular the first synoptic ocean color distributions gathered by the Coastal Zone Color Scanner, became available. Through analyses of these observations and the first large-scale physical–biogeochemical modeling attempts, a pre-JGOFS understanding of the Arabian Sea emerged. During the 1990s, the in situ and remotely sensed observational databases were significantly extended by regional JGOFS activities and the onset of Sea-viewing Wide Field-of-View Sensor ocean color measurements. Analyses of these new data and coupled physical–biogeochemical models have already advanced our understanding and have led to either an amplification or revision of the pre-JGOFS paradigms. Our understanding of this complex and variable ocean region is still evolving. Nonetheless, we have a much better understanding of time–space variability of biogeochemical properties in the Arabian Sea and much deeper insights about the physical and biological factors that drive them, as well as a number of challenging new directions to pursue.     

A four-component ecosystem model of biological activity in the Arabian Sea

A coupled, physical-biological model is used to study the processes that determine the annual cycle of biological activity in the Arabian Sea. The physical model is a system with a surface mixed layer imbedded in the upper layer, and fluid is allowed to move between layers via entrainment, detrainment and mixing processes. The biological model consists of a set of advective-diffusive equations in each layer that determine the nitrogen concentrations in four compartments: nutrients, phytoplankton, zooplankton and detritus. Coupling is provided by the horizontal-velocity, layer-thickness, entrainment and detrainment fields from the physical solution. Surface forcing fields (such as wind stress and photosynthetically active radiation) are derived from monthly climatological data, and the source of nitrogen for the system is upward diffusion of nutrients from the deep ocean into the lower layer. Our main-run solution compares favorably with observed physical and biological fields; in particular, it is able to simulate all the prominent phytoplankton blooms visible in the CZCS data. Three bloom types develop in response to the physical processes of upwelling, detrainment and entrainment. Upwelling blooms are strong, long-lasting events that continue as long as the upwelling persists. They occur during the Southwest Monsoon off Somalia, Oman and India as a result of coastal alongshore winds, and at the mouth of the Gulf of Aden through Ekman pumping. Detrainment blooms are intense, short-lived events that develop when the mixed layer thins abruptly, thereby quickly increasing the depth-averaged light intensity available for phytoplankton growth. They occur during the fall in the central Arabian Sea, and during the spring throughout most of the basin. In contrast to the other bloom types, entrainment blooms are weak because entrainment steadily thickens the mixed layer, which in turn decreases the depth-averaged light intensity. There is an entrainment bloom in the central Arabian Sea during June in the solution, but it is not apparent in the CZCS data. Bloom dynamics are isolated in a suite of diagnostic calculations and test solutions. Some results from these analyses are the following. Entrainment is the primary nutrient source for the offshore bloom in the central Arabian Sea, but advection and recycling also contribute. The ultimate cause for the decay of the solution's spring (and fall) blooms is nutrient deprivation, but their rapid initial decay results from grazing and self shading. Zooplankton grazing is always an essential process, limiting phytoplankton concentrations during both bloom and oligotrophic periods. Detrital remineralization is also important: in a test solution without remineralization, nutrient levels drop markedly in every layer of the model and all blooms are severely weakened. Senescence, however, has little effect: in a test solution without senescence, its lack is almost completely compensated for by increased grazing. Finally, the model's detrainment blooms are too brief and intense in comparison to the CZCS data; this difference cannot be removed by altering biological parameters, which suggests that phytoplankton growth in the model is more sensitive to mixed-layer thickness than it is in the real ocean.     

Atmospheric-induced variability of hydrological and biogeochemical signatures in the NW Alboran Sea. Consequences for the spawning and nursery habitats of European anchovy

The north-western Alboran Sea is a highly dynamic region in which the hydrological processes are mainly controlled by the entrance of the Atlantic Jet (AJ) through the Strait of Gibraltar. The biological patterns of the area are also related to this variability in which atmospheric pressure distributions and wind intensity and direction play major roles. In this work, we studied how changes in atmospheric forcing (from high atmospheric pressure over the Mediterranean to low atmospheric pressure) induced alterations in the physical and biogeochemical environment by re-activating coastal upwelling on the Spanish shore. The nursery area of European anchovy (Engraulis encrasicolus) in the NW Alboran Sea, confirmed to be the very coastal band around Malaga Bay, did not show any drastic change in its biogeochemical characteristics, indicating that this coastal region is somewhat isolated from the rest of the basin. Our data also suggests that anchovy distribution is tightly coupled to the presence of microzooplankton rather than mesozooplankton. Finally, we use detailed physical and biological information to evaluate a hydrological-biogeochemical coupled model with a specific hydrological configuration to represent the Alboran basin. This model is able to reproduce the general circulation patterns in the region forced by the AJ movements only including two variable external forcings; atmospheric pressure over the western Mediterranean and realistic wind fields.