岸滩侵蚀的环境工程观念

本文从环境工程的角度讨论了岸滩侵蚀问题中建立分析模型的基本框架.讨论了岸滩岩土介质在风浪潮作用下,根据不同的侵蚀准则所建立的岸滩沉积物在近海迁移和传输的模型.得出了岸滩的侵蚀、演变过程由三相组成的结论,第一相是与饱和多孔介质经受动力载荷变形和损伤相联系的固态相;第二相是关于介质侵蚀和剥离的流-固态混合相;第三相是流动和沉积物运输的流体相.从分析讨论还可以看出,岸滩侵蚀演化的模拟分析可在岸滩介质的动力固结、悬浮介质扩散漂移及海浪流体动力学理论相互交叉的基础上,针对海岸环境工程问题中的观念和现象来建模并完成.研究表明,在分析海滩侵蚀和海岸演化过程的机理时,采用海洋环境工程学中的相关方法可以得到更符合实际状况的结果.用损伤力学方法建摸研究岸滩介质的侵蚀和沙化过程,可以将海岸沉积物的迁移速率描述为海床面上的等效摩擦剪应力、损伤状态、侵蚀参数及介质的孔隙冲蚀率的函数.在岸滩侵蚀和演化机理研究中将海岸沉积物的纵向迁移和横向迁移理论相结合的模型有一定的优越性,这为岸滩侵蚀与海岸演变提供了定量的分析方法.     

Sediment Flux to the Sea as Influenced by Changing Human Activities and Precipitation: Example of the Yellow River,China

Since the 1970s, the sediment flux of the Yellow River to the sea has shown a marked tendency to decrease, which is unfavorable for wetland protection and oil extraction in the Yellow River delta. Thus, an effort has been made to elucidate the relation between the sediment flux to the sea and the drainage basin factors including climate and human activities. The results show that the sediment flux to the sea responds to the changed precipitation in different ways for different runoff and sediment source areas in the drainage basin. If other factors are assumed to be constant, when the annual precipitation in the area between Longmen and Sanmenxia decreases by 10 mm, the sediment flux to the sea will decrease by 27.5 million t/yr; when the precipitation in the area between Hekouzhen and Longmen decreases by 10 mm, the sediment flux to the sea will decrease by 14.3 million t/yr; when the precipitation in the area above Lanzhou decreases by 10 mm, the sediment flux to the sea will decrease by 17.4 million t/yr. A multiple regression equation has been established between the sediment flux to the sea and the influencing factors, such as the area of land terracing and tree and grass planting, the area of the land created by the sediment trapped by check dams, the annual precipitation, and the annual quantity of water diversion by man. The equation may be used to estimate the change in the sediment flux to the sea when the influencing variables are further changed, to provide useful knowledge for the environmental planning of the Yellow River drainage basin and its delta.     

监测与管理并重,为建设海上大连赢得先机

针对近年来海域环境污染的重点和热点问题 ,阐述了大连市环境监测站在强化自身能力建设、海洋环境监测、环境科研及环境管理方面所做的有益探索     

渤海湾污水海洋处置研究

为研究污水海洋处置京城 渤海湾这类具有缓坡潮间带海湾的可行性，应用动边界数学模型对这一问题进行了数值模拟研究，并参考已经运行的处置工程对渤海湾污水海洋处置工程进行了经济分析，提出了污水海洋处置的优化方案。     

嘉兴市污水海洋处置工程近区稀释扩散物理模型和数学模型研究

结合嘉兴市污水海洋处置工程，以排污口近区污水稀释扩散规律进行了物理模型和数学模型研究，数学模型采用美国国家环保局的UM模型、香港大学李行伟教授的Jetlag3模型以及我们自行研制的积分控制模型。结果表明，Jetlag3模型计算值和物理模型的试验结果相差不大。     

海洋溢油和含油废水排放的对策

海洋是人类赖以生存的第二大场所。开发海洋石油资源必须做到既要把石油资源开采出来，又要保护海洋生态环境不遭受污染。概述了溢油的污染机理、计算方法、预防措施。     

热带海—气的相互作用与地球自转—用天文方法预测ENSO事件

本文介绍了热带海洋、大气的相互作用,着重描述了它们与地球自转年际速率变化的关系和物理过程的联系,以及用天文观测的日长变化资料预测ENSO事件的方法和尝试.     

Similarity theory and parameterization of mixing in the upper ocean

Boundary layers with small thermal and mechanical inertia are close to steady-state conditions. This underlies the Monin-Obukhov similarity theory and explains why the surface values of the fluxes can be chosen as external parameters. For fluids with large thermal inertia, such as the ocean, the thermal time scale is relatively large, and the density flux is a complex function of depth; thus, the external thermal forcing is no longer a governing parameter. However, the mechanical inertia of the upper ocean is about three orders of magnitude smaller than the thermal inertia. Consequently, the upper ocean can be considered as steady-state in the dynamic sense, to any dynamic property depends primarily on the depth, the surface momentum flux, and the vertical density structure. This property allows us to suggest an alternative formulation of the similarity theory for the stratified boundary layers through specification of a new stratification parameter which characterizes the internal density structure instead of the external density flux. The turbulent mixing coefficient is derived as dependent on the stratification parameter. The latter includes the surface stress and the integral density deficit for the entire layer above. The general form and the asymptotic behavior of the nondimensional turbulent mixing coefficient as a function of the stratification parameter are obtained using dimensional considerations. Determination of numerical parameters is based on 8 years of temperature profiles acquired at the Ocean Weather Ship (OWS) PAPA. Finally, a method for calculating the profile of the turbulent mixing coefficient is obtained. This approach reproduces the 8-year evolution of the upper ocean with the maximum rms difference of approximately 1C and the bias of 1C over the depth range 0–150 m. Additional 1-year simulation of the upper ocean at OWS CHARLEY and 9-year simulation at OWS NOVEMBER confirms reasonable applicability of this approach. The proposed simple turbulent mixing scheme reproduces the evolution of the upper ocean with accuracies similar to those obtained using much more complicated models.     

深圳东西部近岸海域水质评价、对比与分析

对基于河流的水质标识指数法进行了改进,使其适用于海域。将改进后的标识指数法应用于深圳市近岸海域水质评价,并对东西部海域水质进行了对比与分析。研究结果表明,西部海域的活性磷酸盐、无机氮、非离子氨和大肠茵群超标,全部劣于四类标准;东部海域水质良好,达到第一类或第二类标准。主要原因是西部近岸海域生态遭受破坏,陆源污染未得到有效控制,并且受珠江口污染影响,而东部海域则生态环境保护较好,入海污染源较小。标识指数法不仅可以判断水质是否超标,而且能够确定水质具体类别,具有计算简单、分析结果直观等优点,值得推广使用。     

浅海目标辐射噪声矢量场特性实验研究

对浅海目标辐射噪声的矢量场特性和矢量噪声测量技术的相对优势开展了实验研究,对实测数据进行了相关的矢量信号的处理与分析。测试结果表明,目标辐射噪声矢量场相关性很强;与传统标量测量方法相比,在浅海低信噪比条件下,矢量法有效提高了目标辐射噪声测量增益。