【作者】 李杰；

【导师】 吴增茂；

【作者基本信息】 中国海洋大学 ， 大气物理学与大气环境， 2005， 硕士

【摘要】 黄海冷水团是我国陆架浅海上一个重要的海洋现象,一直倍受我国物理海洋学家关注。近年来对黄海冷水团水域的物理及生物化学特性的研究受到了周边国家的重视并取得了重要进展,但是生态动力学方面的数值研究仍很缺乏。本文的主要研究目标是对已经建立的黄海冷水团水域水层—底栖耦合生态系统垂直一维模型进行改进及参数优化,对该海区浮游生态系统基本生态变量垂向结构的季节变化特征、物流能流结构特征进行模拟分析,并着重对初级生产力、新生产力以及浮游生态效率和微食物环的贡献等问题进行比较详细的动力学研究,以增进对黄海生态动力学的深入理解。 首先根据黄、东海生态综合调查资料和前人的研究成果,分析了黄海冷水团水域水层生态系统的基本特征。然后根据2003年9月黄、东海海面太阳辐射的观测资料,验证了应用Dobson & Smith模型计算海面太阳辐射和构造辐射场的可行性,为缺乏海面太阳辐射实测资料的海洋生态系统模拟提供了有力保证。接下来对生源要素的模拟结果进行了分析,并着重对黄海冷水团的初级生产力、新生产力进行了分析研究。本文的最后一部分针对模拟区域初级生产力低下而浮游生态效率却比较高的问题进行分析,说明了微食物环在浮游动物的生产过程中所扮演的举足轻重的角色。 研究采用的模型共分为水层和底栖生态系统两部分,并考虑了二者之间的耦合。模型采用箱式模型,将模拟区域水层根据温跃层与真光层位置由上而下分为三个箱子。三个箱子都包含了水层生态亚模型,它主要考虑了浮游植物(P)、浮游动物(Z)、颗粒有机物(POC)、溶解有机物(DOC)、总无机氮(TIN)、总无机磷(TIP)和溶解氧(DO)7个生态变量;底层箱子还考虑了底栖生态亚模型,其中包含大型底栖生物(MacroB)、小型底栖生物(MeioB)、底栖细菌(Bbac)、沉积物有机碎屑(Det)、间隙水中的总无机氮(BTIN)和总无机磷(BTIP)6个生态变量。水层和底栖生态系统的耦合是通过浮游植物与颗粒有机物的沉降和沉积物中营养盐的溶出实现的。表层箱子考虑了营养盐的大气干湿沉降输送。另更多还原

【Abstract】 The Yellow Sea Cold Water Mass (YSCWM), as an important oceanic phenomenon in the marginal sea of China, is one of the research focus of oceanographers for long time. Though great achievements have been achieved in physical and biochemical oceanography in the YSCWM, the numerical studies of ecosystem dynamics remain scarce. The main purpose of this paper is to explore the seasonal variation of the vertical structure of each variable and the flow characteristics of matter and energy in the ecosystem of the YSCWM based on one-dimensional coupled pelagic-benthic box model. The issues of primary productivity, new production, planktonic ecological efficiency and the impact of microbial loop will be analyzed in detail, to better the understanding of the eco-dynamics in the Yellow Sea.The basic ecosystem characters in the YSCWM are outlined according to former studies and observation in the Yellow Sea and the East China Sea in the first part of this paper. Then the feasibility of using Dobson and Smith model to calculate daily sea-surface solar radiation in the Yellow Sea is tested, which provide assurance for the ecosystem numerical study with lacking of solar radiation observation on the ocean surface. The simulated results of primary productivity and new production in the YSCWM are analyzed in the following part. The last part illustrates that the microbial food loop plays an important role in the course of zooplankton production in the region of low primary productivity. The last two parts is the emphasis of this paper.The model is divided into three boxes according to the depths of thermocline and euphotic layer. All the three boxes contain pelagic submodel which includes seven state variables such as phytoplankton (P), zooplankton (Z), particle organic carbon (POC), dissolved organic carbon (DOC), dissolved oxygen (DO), total inorganic nitrogen (TIN) and total inorganic phosphate (TIP). Besides, the lower box containsthe benthic submodel which includes six variables such as macrobenthos (MacroB), meiobenthos (MeioB), benthic bacteria (Bbac), detritus (Det), total benthic inorganic nitrogen (Btin) and total benthic inorganic phosphate (Btip). The pelagic-benthic coupling is realized by the deposition of phytoplankton and POC into detritus and the transportation of nutrient elements from the bottom to the pelagic. In this model, the effect of microbial loop is considered in a parameterization way. The vertical flux between compartments of the model system is also taken into account.The seasonal variation of each variable in the YSCWM ecosystem is simulated by the coupled pelagic-benthic model, and the results matches well with the observational data and the related literatures, which indicated that the model could depicts the main characters of seasonal variation in the YSCWM ecosystem. The relationship between each variable and the ecologic difference between different layers are simulated reasonably. Generally, the model is competent for the simulation of matter and energy flow characteristics of the ecosystem in the YSCMW.Through the simulation and analysis to the primary productivity and new production in the YSCWM, the annual mean primary productivity estimated as 239mgCm-2d-1, and f-ratio is calculated about 33% according to analyze the origin ofinorganic nitrogen. So the new production is about 28.8 mgCm-2 d-1. The result also reveals that, in the period of time when the Cold Water Mass exists, the nutrient is deficient so that the production of the phytoplankton is restricted, just an insignificant bloom appears in the late fall. However, in this period, the biomass of zooplankton is in the same order as the phytoplankton and the values are relatively close, In the area of YSCWM, the simulated planktonic ecological efficiency is as high as 0.47. Therefore, the microbial loop plays a crucial role in the cycle flow of the matter and energy. Besides, the simulation results also show that 60% of the organic carbon of zooplankton growing requires is supplied by the microbial loop. The contribution of POC to the zooplankton production is less than the phytoplankton. These three energy flows have obvious seasonal variability. Compared with the observation and the literatures, it is found that the simulation results of the model are reasonable andauthentic.更多还原