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1.
海洋浮游生态系统动力学模式的研究   总被引:9,自引:0,他引:9  
分析了海洋浮游生态系统动力学模式的结构,讨论了其研究现状。90年代以来海洋浮游生态系统动力学模式的特点是:状态变量的个数较以前有所增加,从2-4个增加至3-7个生物过程的描述更加细致;注意刻画物理过程的作用,特别是垂直方向上湍流的交换作用;利用或改进原来的模式,研究新问题;模式仍以一维为主,同时三维耦合模式也得取发展和应用;区域仍以北大西洋为主,也出现了研究赤道太平洋、阿拉伯海、东海等海区的工作。  相似文献   

2.
以Logistic模型为基础,考虑捕捞行为及其所造成的污染对浮游生物的削弱作用,并考虑浮游生态系统具有一定的自净能力,建立了一个新的海洋浮游生态系统非线性动力学模型。分析了模型的非线性动力学特性,并得出了模型的稳定性条件和发生Hopf分岔条件,在此基础上,深入分析了捕捞强度参数的变化对系统稳态的影响,并且用数值模拟验证了理论分析结果的正确性。  相似文献   

3.
海洋浮游生态系统连续介质动力学模型的建立   总被引:3,自引:0,他引:3  
运用质点、连续介质和状态变量等观点来描述海洋浮游生态系统,根据生物生命运动、生化反应、水动力学和物质守恒等基本规律,建立海洋浮游生态系统动力学的模型方程。推广地球流体力学的湍流二阶闭合理论,建立实用的雷诺平均生态系统动力学模型方程及其二阶相关项的闭合模型方程,将生态动力学状态变量的湍扩散参数化。本文还讨论了该模型与通常的N-P-Z-D模型的关系,提出了其适用范围。  相似文献   

4.
海洋浮游生态系统连续介质动力学的模型的建立   总被引:3,自引:0,他引:3  
运用质点、连续介质和状态变量等观点来描述海洋浮游生态系统,根据生物生命运动、生化反应、水动力学和物质守恒等基本规律,建立海洋浮游生态系统动力学的模型方程,推广地球流体力学的湍流二阶闭合理论,建立实用的雷诺平均生态系统动力学模型方程及其二阶相关项的闭合模型方程,将生态动力学状态变量的湍扩散参数化,本文还讨论了该模型与通常的N-P-Z-D模型的关系,提出了其适用范围。  相似文献   

5.
本文基于南海SEATS站的观测资料,利用垂直一维海洋生态系统动力学模式(MEM-1D)模拟了南海北部生态要素垂直结构的季节变化。结果表明,南海北部表层Chla浓度具有明显的季节变化特征,夏季呈现低值(<0.05 mg·m-3),冬季呈现高值,12月为0.38 mg·m-3。春季,风速相对变小,垂直混合变弱,次表层Chla浓度极大值现象形成(80~100 m),并可一直持续到10月末。冬季,海表温度降低,东北季风爆发,垂直混合增强,出现表层水华现象。浮游动物和细菌的垂直结构相似,冬季上层水体中浮游动物和细菌出现最大值,分别为13 mg·m-3和18 mg·m-3。3~10月细菌(12 mg·m-3)同浮游动物(14 mg·m-3)一样出现次表层最大值,其存在深度与浮游动物相似。  相似文献   

6.
珠江口水域浮游生态系统中磷的循环及其效应评估   总被引:1,自引:0,他引:1       下载免费PDF全文
根据现场调查和室内试验工作, 计算珠江口水域浮游植物有效光合作用水体体积, 同时研究浮游动物摄食行为对磷再生的补偿作用, 进而对该水域磷的生物利用状况进行初步评估。分析珠江口2002—2003年的数据发现, 珠江口水域浮游植物有效进行光合作用水体的体积存在季节性变化, 枯水期约为9.7×104m3, 而丰水期约为6.6×104m3。该水域总初级生产量在枯水期约为36kg.d-1, 在丰水期约为31kg.d-1, 呈现枯水期大于丰水期的特点。浮游动物的摄食作用可促进水体中磷的再生, 这部分磷可满足浮游植物生长对磷需求的1.5%—15.6%, 并呈现丰水期大于枯水期的特点。浮游动物摄食作用直接释放的量远大于其自身生理周转释放的量。  相似文献   

7.
8.
赤潮藻类营养盐限制方程的非线性动力学研究   总被引:3,自引:2,他引:3  
以赤潮代表性藻类-硅藻为研究对象,利用生物生长的生化机理,并考虑在海洋富营养化条件下氮和磷的浓度变化对藻类生长的影响及底物消耗和反馈机制,建立了新的藻类生长非线性动力学模型。首次利用现代非线性动力学的方法,研究了其解析解的分岔行为。指出了磷是影响藻类生长的限制营养盐因子,并对模型进行了仿真。文章对赤潮发生的预警和预测有一定的参考价值。  相似文献   

9.
渤海赤潮藻类生态动力学模型的非线性动力学研究   总被引:11,自引:3,他引:11  
基于渤海典型赤潮藻类——中肋骨条藻 ,考虑浮游动物的捕食、光照及营养物质的作用 ,建立了渤海湾的浮游动物—藻类—营养物质三者的动力学模型。运用现代非线性动力学理论着重分析了模型的稳定性及分岔行为。研究了多个参数对藻类生长的影响 ,发现某些参数对藻类的生长影响不大 ,而某些参数则会致使藻类模型出现分岔乃至混沌行为 ,并给出了这些参数的阀值 ,这与赤潮的形成 (爆发性增殖 )密切相关 ;并根据渤海湾的赤潮数据进行了有效的数值模拟 ,所得结果对于研究赤潮的形成机理有一定的参考价值  相似文献   

10.
本文采用Boussinesq近似,利用地转动量近似(GMA)方法,研究了大气Ekman层的三维非线性动力学特征,得到了Ekman层中三维风速分布的解析解,着重讨论了热成风对Ekman层水平风速分布的影响,对传统的求垂直速度的方法进行了改进。  相似文献   

11.
基于营养盐、赤潮藻类、植食浮游动物之间的食物链关系,考虑到由于海洋内微生物分解动植物遗体对营养盐的补充以及物理因素导致的流失,文中建立了营养盐一赤潮藻类一植食性浮游动物相互作用的耦合生态动力学模型。运用现代非线性动力学理论,对模型解的动力学稳定性进行了分析。结果表明,随着参数的变化,系统稳定性也随之变化,甚至出现HOPF分岔现象。  相似文献   

12.
分4部分介绍互联网上与海洋生态系统动力学研究有关的信息资源、主要网址及其主要内容:(1)海洋生态系统模拟研究;(2)海洋科学研究组织和国际研究计划;(3)网上新闻讨论组;(4)海洋生态杂志。  相似文献   

13.
水层-底栖耦合生态动力学研究的某些进展   总被引:6,自引:3,他引:6  
概述浅海生态系的水层系统与底栖系统耦合的基本原理,着重介绍有机质沉降动力学、底栖生态系统对有机质的响应、生物沉降和侧向平流、生物扰动和沉积物再悬浮研究的进展,结语中提出应予优先支持研究的科学问题。  相似文献   

14.
The Continuous Plankton Recorder (CPR) Type I was first used in Antarctic waters during the 1925–1927 Discovery Expedition, and has been used successfully for 70 years to monitor plankton in the North Sea and North Atlantic Ocean. Sixty-five years later the CPR as a Type II version returned to Antarctic waters when the Australian Antarctic Division initiated a survey of the Southern Ocean on RSV Aurora Australis south of Australia and west to Mawson. The objectives are to study regional, seasonal, interannual and long-term variability in zooplankton abundance, species composition and community patterns, as well as the annual abundance and distribution of krill larvae. The survey covers a large area from 60°E to 160°E, and south from about 48°S to the Antarctic coast—an area of more than 14 million km2. Tows are conducted throughout the shipping season, normally September to April, but occasionally as early as July (midwinter). The large areal and temporal scale means that it is difficult to separate temporal and geographical variation in the data. Hence, CPRs are now also towed on the Japanese icebreaker Shirase in collaboration with the Japanese Antarctic programme. Shirase has a fixed route and time schedule, travelling south on 110°E in early December and north on 150°E in mid-March each year, and will serve as an important temporal reference for measuring long-term interannual variability and to help interpret the Australian data. Since 1991, over 90 tows have been made, providing over 36,000 nautical miles of records. The most successful seasons to date have been the 1997/1998, 1999/2000 and 2000/2001 austral summers with 20, 31 and 26 tows, respectively. The 1999/2000 season included a unique, nearly simultaneous three-ship crossing of the Southern Ocean along 25° 30’E, 110°E and 157°E. Typical CPR tows show very high abundance of zooplankton in the uppermost 20 m of the permanently open ocean zone between the sea-ice zone and the Sub-Antarctic Front; this is an area thought to be oligotrophic. Appendicularians and small calanoid and cyclopoid copepods dominate the plankton. By comparison the surface waters of the sea-ice zone have low species diversity and abundances. Zooplankton data, and hence distribution patterns, can be time- and geo-coded to GPS data and environmental data collected by the ships’ underway monitoring system (e.g. fluorescence, water temperature, salinity, and meteorological data).  相似文献   

15.
海洋生态经济系统非线性动力学模型的建立及分析,对我国海洋生态经济发展乃至社会经济的发展都具有重要意义.建立了新的海洋生态经济系统动力学模型,研究了模型的稳定性和分岔现象,揭示了该系统的非线性动力学特性.  相似文献   

16.
Yuriy N.  Tokarev 《Marine Ecology》1996,17(1-3):187-196
Abstract. Some hydrophysical environmental parameters ( e.g . temperature, salinity, transparency, flows, erc .) are known to profoundly affect the structural and functional characteristics and species composition of plankton communities. The purpose of the present work was to assess the opposite - the influence of qualitative and quantitative characteristics of plankton on some optical (light transmission. optical density) and acoustic (sound volume backscattering strength) characteristics in the Black Sea. The influence of specific features (shape, size and color) of planktonic unicells on light attenuation in seawater was examined in laboratory experiments. The data from field studies on variability of statistic characteristics of sound volume backscattering strength in upper productive water layer, depending on species composition and numbers of zooplankton, are given.  相似文献   

17.
为了研究随机干扰因素与藻类生态系统稳定性之间的相互关系,运用随机非线性理论建立了藻类—营养盐的随机非线性动力学模型,采用随机平均法和奇异边界理论对模型的稳定性进行了分析,结果表明随机因素对稳定性的影响很大。随机因素可以使系统稳定性发生质的变化。  相似文献   

18.
Seasonality of Plankton Assemblages in a Temperate Estuary   总被引:3,自引:0,他引:3  
Abstract. Synoptic measurements of temperature, salinity, nutrients, primary productivity, chlorophyll a, and abundance and composition of phytoplankton, zooplankton, and ichthyoplank-ton were made over an annual cycle on the Peconic Bay estuary (Long Island, New York, USA). There were pronounced seasonal fluctuations in all variables measured. During the warmer season, the plankton was dominated by nanophytoplankton (athecate microflagellates and chlorophytes, short chains of diatoms), small zooplankton (copepod nauplii, copepodites, and adults of small copepod species) and gelatinous carnivores (ctenophores and medusae). During the colder season, the plankton was dominated (in terms of primary productivity and chlorophyll a) by netplankton, larger zooplankton (adult copepods) and fish larvae. The winter bloom of apparent netplankton (> 20 μm fraction) was largely an artifact of the screening method employed, in that long chains of a diatom with small individual cell size (Skeletonema costatum) comprised 84.4–97.8% of the phytoplankton present. There was a significant negative relationship over the year between length of diatom chains and number of smaller zooplankton. For this reason, as well as initiation of the winter bloom during a period of declining levels of both light and zooplankton, inception of the bloom appeared more related to release of zooplankton grazing pressure than to illumination. Temporally offset pulses of ctenophores and other zooplankton during the warmer season suggest substantial predation by ctenophores. Apparent decimation of copepod populations by ctenophore predation in late summer and fall immediately preceeded inception of the winter diatom bloom. Larval Ammodytes americanus were the dominant ichthyoplankton, and these co-occurred in winter with increased abundances of larger adult copepods of species upon which A. americanus is known to feed. With certain modifications the patterns recorded for Peconic Bay corresponded to both of two generalized trophic pathways proposed by Greve & Parsons (1977) for temperate waters: nanoplankton → small zooplankton → gelatinous zooplankton carnivores or netplankton → larger zooplankton → young fish. The former pattern characterized the warmer season, and the latter the colder season. Comparison of patterns in Peconic Bay with those in some other temperate estuarine and coastal waters suggests similarity, particularly for estuaries of the northeastern United States.  相似文献   

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