排序方式： 共有51条查询结果，搜索用时 109 毫秒
31.
亚洲沙尘的远距离输送及对海洋生态系统的影响 总被引：6，自引：0，他引：6
亚洲沙尘是全球沙尘的重要组成部分,其环境效应已得到广泛关注,但至今对亚洲沙尘输送/沉降—海洋生态系统响应—辐射活性气体海气交换—间接气候效应这一过程的认识却是非常初步的。亚洲沙尘存在3个主要源区,对其排放强度的认识仍存在较大的不确定性。亚洲沙尘可以通过长距离输送而影响到广大的北太平洋,其传输路径和影响范围决定于沙尘的来源、粒子谱分布与大气环流特征等因素。沙尘沉降是海洋营养物质和污染物质的来源之一,但沉降通量的估算结果仍有待进一步验证,而对海洋生态系统的作用机制及其反馈还缺乏足够的了解。论文在综述国内外相关研究的基础上,提出了“亚洲沙尘与海洋生态系统”（Asian Dust and Ocean EcoSystem,ADOES）研究计划的科学目标和主要研究内容。 相似文献
32.
Tidal residual is very important to the transport of water particles, nutrients, plank-ton, etc. in the coastal sea. Eulerian scheme and Lagrangian scheme are two different ways to get the time averaged residual. Solution of the Bohai Sea‘s hydrodynamic system using a semi-implicit layer aver-aged numerical model yielded different direction Eulerian and Lagrangian tidal residuals. The latter were stronger than the former in most sea areas. Their different directions produced different ciretdation pattern in some areas. Compared with the Eulerian residual, the Lagranglan residual seemed to be more in accord with the observation. 相似文献
33.
A zero-dimensional box model (PNCMjzb) with six state variables (ammonium, nitrate, dissolved organic nitrogen, phytoplankton, zooplankton and detritus) was developed to study nitrogen cycling in the Jiaozhou Bay pelagic ecosystem. The dominant processes within these compartments are considered with nitrogen as flow currency. Phytoplankton and zooplankton are treated as separate state variables, assuming that the species composition was dominated by two or three species the dynamic constants of which are similar and that they represent the entire plankton community. The microbial loop has not been integrated explicitly in the model. The turnover of bacteria is included implicitly in processes such as detritus decomposition, DON remineralization, pelagic nitrification and denitrification. The model is driven by two forcing variables, viz. water temperature and light intensity. Historical data from the1980s and 1990s were compiled and used for model calibration. In this paper (part Ⅰ), the consideration of every main compartment in the model is interpreted in detail. And the applied equations and parameters are presented. The main results from the simulations together with discussion about phytoplankton dynamics and primary production in Jiaozhou Bay are presented in the next paper (part Ⅱ). 相似文献
34.
A simple diagnostic simulation of the annual cycling of the surface specific photosynthesis rate (SPR) in Jiaazhou Bay is described in this paper. Light intensity, temperature and nutrients(nitrate ammonia, phosphate) were considered as main factors controlling photosynthesis of phytoplankton and were introduced into the model by different function equations. The simulated variation ofspecific photosynthesis rate coincided with the measured data. Analysis of the effect of every factor onphotosynthesis indicated that the variation of photosynthesis rate was controlled by all these three factors,while temperature showed good correlation with SPR as measurement showed. This diagnostic simulationyielded the values of some parameter relating with the photosynthesis in Jiaozhou Bay. 相似文献
35.
冯士筰 《中国海洋大学学报(自然科学版)》1978,(1)
给了光滑壁界附近湍流平均运动速度分布对数律的一点修正;以某些实验曲线进行了检验并加以分析,特别指出了,经典对数律不能描述完整的湍流核心区,而经过修正后才可能真正描述完整的湍流核心区。 相似文献
36.
引言 Defant在长渠的潮波方程中引入了分潮波的时间因子exp(-iσt)(其中σ为分潮波的园频率,t为时间变量,i=(-1)~(1/2)),从而建立了不含时间变量的分潮波方程,并首先使用了数值解法。电子计算机问世后,Hansen首先将这一方法推广至二维真实海域——北海,给出了所谓“潮波边值问题”的数值方法。此后,等人又将该方法推广至三维空间的情形。然而,Hansen曾断言,这种分潮波的边值问题方法 相似文献
37.
在温跃层深度存在空间变化的条件下，建立约化重力热带海洋波致环流动力学模型。根据模型，热带海洋波致环流可看作是“广义地转运动”；波致子午向水体输运方程具有和Ｓｖｅｒｄｒｕｐ输运方程相似的形式；特别是波致环流对赤道准定常流系的“正负”贡献受制于温跃层深度的空间变化特征 相似文献
38.
绪言 东中国海环流是控制本海区水文气象状况的最重要因子。但至今尚无完整的动力学理论分析,这是因为对产生该海区环流的主要因子了解不够,加之它岸形复杂,水深变化很大,难以用一个解析模式将全海区概括起来。目前在黑潮深水区进行了一些动力计算,得到较好的结果,但在近岸浅水区由于零面选取上的困难,动力计算方法无法使用。因此,利用数值模式来模拟全海区的环流成为研究东中国海环流的重要途径之 相似文献
39.
f—平面上的宽陆架诱导阻尼波 总被引：1，自引：1，他引：1
由于陆架区资源的开发和利用以及污染、地震海啸和风暴潮预报等等的实际需要,近廿年来,随着浅海动力学中的陆架动力现象越来越受到人们的关注,陆架诱导波的研究也得到了相应的进展.特别是,我国东临宽广的浅水陆架区域,它蕴藏着丰富的石油和水产等资源,又不断遭到风暴潮的袭击,显然,宽陆架诱导阻尼波的探讨是具有特殊重要意义的. 相似文献
40.
冯士筰 《中国海洋大学学报(自然科学版)》1994,(Z1)
随着全球社会和经济的发展,特别是近10年来,由于现代化工业进程和海洋开发活动的加强,海洋污染和环境退化正以惊人的速度加剧。海洋环境保护已成为当今世界各国政府和人民共同关心的重大问题。1992年在联合国环境与发展大会上把海洋环境保护列入《21世纪议程》。我国政府热烈响应、积极支持,也提出了《中国21世纪议程》的优先项 相似文献