椒江口海域围填海强度及环境影响分析          下载免费PDF全文

钱健  陈立红  丰卫华  向芸芸  王志富 《海洋开发与管理》2018,35(9):62-66

文章对近10年来椒江口两岸主要的围填海工程进行了统计,利用基于围填海强度等级控制理念的围填海潜力评估方法,对椒江口海域的围填海强度及围填海潜力进行了定量评估,并对其造成的环境影响进行了分析。分析结果显示,椒江口海域虽然仍有一定的围填海潜力,但围填海压力较大,椒江口大规模的围填海工程对海岸带地形地貌、海域水文动力环境、滨海湿地生态系统、海洋水环境质量、海洋生物资源等均存在负面影响,为此提出了强化围填海管控、重视海岸带整治修复等建议,以期为椒江口的围填海管控和生态环境保护提供参考。  相似文献   

南海风暴潮对风场和外围海水敏感性研究     

李健  刘清容  阮成卿  訚忠辉  冀承振 《海洋科学》2018,42(2):99-107

为探索来自西北太平洋台风风暴潮与南海局地生成台风风暴潮不同,本研究在假设两种台风气象条件相同情况下,研究随台风而来外围海水所形成增水对南海沿岸的影响。以0814"黑格比"强台风风暴潮为基础,使用ROMS(regional ocean modeling system)模式进行数值模拟并通过设计对比试验方法进行研究,研究发现在台风登陆时引起的增水最大,最大增水出现在台风路径右侧,其中在沿岸区域,外围海水形成增水约占总增水10%,且大约3 h后出现增水回震现象。同时,设计对比试验,研究来自西北太平洋台风风暴潮对台风路径、台风强度、台风移动速度和流入角等气象条件敏感性,并获得与前人一致的结果。  相似文献   

Hydrological management strategies for the control of algal blooms in regulated lowland rivers     

Jian Li  Wei Yin  Haiyan Jia  Xiaokang Xin 《水文研究》2021,35(6):e14171

Reservoirs of lowland floodplain rivers with eutrophic backgrounds cause variations in the hydrological and hydraulic conditions of estuaries and low-dam reservoir areas, which can promote planktonic algae to proliferate and algal bloom outbreaks. Understanding the ecological effects of variations in hydrological and hydraulic processes in lowland rivers is important for algal bloom control. In this study, the middle and lower reaches of the Han River, China, a typical regulated lowland river with a eutrophic background, are selected. Based on the effect of hydrological and hydraulic variability on algal blooms, a hydrological management strategy for river algal bloom control is proposed. The results showed that (a) differences in river morphology and background nutrient levels cause significant differences in the critical threshold flow velocities for algal bloom outbreaks between natural river and low-dam reservoir sections; there is no uniform threshold flow velocity for algal bloom control. (b) There are significant differences in the river hydrological/hydraulic conditions between years with and without algal blooms. The average river flow, water level and velocity in years with algal blooms are significantly lower than those in years without algal blooms. (c) For different river sections where algal blooms occur and to meet the threshold flow velocities, the joint operation of cascade reservoirs and diversion projects is an effective method to prevent and control algal blooms in regulated lowland rivers. This study is expected to deepen our understanding of the ecological significance of special hydrological processes and guide algal bloom management in regulated lowland rivers.  相似文献   

Stokes漂流对全球海表面温度模拟的影响     

肖林  史剑  蒋国荣  刘子龙  张成成 《海洋通报》2018,(1):55-87

Stokes漂流对海洋上混合层中的流场和温度场结构具有不可忽视的作用。本文基于WAVEWATCHⅢ海浪模式模拟的海浪要素计算得到Stokes漂流,将其引入SBPOM模式的动量方程中,从体积输运的角度研究Stokes漂流对全球海表面温度的影响。分析发现Stokes漂流与Stokes输运在全球呈现高纬度强于中低纬度的带状分布特征,且这种流动与输运对全球海表面温度具有降温作用,该降温作用的分布与全球Stokes输运强度相对应,高纬降温作用大于中低纬度,特别是南极绕极流海域平均降温明显大于其余海域,最大降温可达1.5℃,且全球月平均降温超过0.1℃。  相似文献   

On the electron density diagnostics of silicon <Emphasis Type="SmallCaps">viii</Emphasis> ion in solar transition region     

Jian He  Qingguo Zhang 《Astrophysics and Space Science》2018,363(9):194

The conditions for accurate electron density diagnostics in the solar transition region are discussed, and result shows that lines from Si?viii can provide an excellent tool for electron density diagnostics of the emitting plasma. For the Si?viii 1440.50 Å and 1445.75 Å lines, the principle of the electron density diagnostics is discussed for any intensity ratio. By the observed intensity ratio, the diagnostic results of the electron density for the quiet sun and the active region are calculated, and results indicate that in the quiet sun, the averaged electron density is \(\log (N_{e}) = 8.63\); while in the active region, the averaged density gets the maximum \(\log (N_{e}) = 8.86\) in the active region (B), and gets the minimum \(\log (N_{e}) = 8.38\) in the active region (E), where the electron density is in the unit of cm^?3. Finally, the relationship of intensity ratio and electron density is discussed, in the case of lower and higher electron density limits. This discussion is significant in the electron density diagnostics, which will be important for study on coronal heating and acceleration of solar wind.  相似文献   

建鲤基因组DNA的RAPD分析     

董在杰  朱健  袁新华  王建新  姜焱 《广东海洋大学学报》2002,22(1):3-6

用 1 5个随机引物对建鲤基因组DNA进行RAPD分析 ,结果显示 ,建鲤群体内的遗传相似系数为 0 91 81± 0 0 73 8,多态位点比例为 0 41 67,平均杂合度为 0 1 884。表明建鲤种质较纯 ,群体内的遗传变异程度较小。建鲤优良性状产生的分子学基础是等位基因的杂合程度较高  相似文献   

观驾山—黑岛一带信息量法找金研究     

简文星  吕贻峰  秦松贤  刘吉平 《国土资源》1996,(2)

本文以成矿地质模型为依据，对观驾山—黑山岛一带的化探、物探、遥感及地质等信息变量进行了详细的分析，选取了１０个信息变量２４个标志状态；在此基础上，运用信息量法对研究区内４５８个单元的信息量值进行计算，并由此确定了研究范围内的成矿远景区。事实表明，研究区信息量成矿预测是非常有效的  相似文献   

一种基于自证明公钥的可公开验证的认证加密方案     

彭银桥  甘元驹  邓锐  彭凌西  陈月峰 《广东海洋大学学报》2005,25(3):73-75

针对现有的基于证书的认证加密方案通信量和计算量大的缺点,提出了基于自证明公钥的可公开验证的认证加密方案。详细阐述了方案的系统初始化、签名生成、消息恢复验证以及公开验证4个阶段,方案的安全性是基于求解离散对数的困难性(DLP)和强单向hash函数(OWFH)的不可逆。该方案在没有签名者的协作下,任何验证者都可验证签名者的诚实性,在验证签名的同时可认证签名者的公钥,因而减少了存储空间、通信量和计算量。  相似文献   

The efifect of wave breaking on surface wave imaging by Synthetic Aperture Radar     

孙建  管长龙  史剑 《中国海洋湖沼学报》2006,(1)

The effect of ocean wave breaking as a non-Bragg mechanism on backscattering cross-section and modulation transfer functions (MTF) of radar was investigated based on Bragg resonance theory and parametric method. The result showed that the additional effect of wave breaking on backscattering cross-section is not more than 20% except for the small incident angle of VV polarized electromagnetic (e.m.) wave but is significant for HH polarized e.m. wave. Breaking waves lead to increase in the modulus of tilt modulation MTF and the larger the wind speed, the faster the increase. For large incident angle, the modulus of tilt modulation MTF with wave breaking decreases quickly with incident angle for HH polarization and approach to that without wave breaking for VV polarization. The hydrodynamic MTF increases 30%-60% when considering wave breaking and the increase is larger for HH polarization than for VV polarization.  相似文献   

Tidal effects on temperature front in the Yellow Sea   总被引：5，自引：0，他引：5  

Ma Jian  Qiao Fangli  Xia Changshui  Yang Yongzeng 《中国海洋湖沼学报》2004,22(3):314-321

Temperature front (TF) is one of the important features in the Yellow Sea, which forms in spring, thrives in summer, and fades in autumn as thermocline declines. TF intensity ⋎S _T ⋎ is defined to describe the distribution of TF. Based on the MASNUM wave-tide-circulation coupled model, temperature distribution in the Yellow Sea was simulated with and without tidal effects. Along 36°N, distribution of TF from the simulated results are compared with the observations, and a quantitative analysis is introduced to evaluate the tidal effects on the forming and maintaining processes of the TF. Tidal mixing and the circulation structure adapting to it are the main causes of the TF. Supported by the National Basic Research Program of China (No. G1999043809) and the National Science Foundation of China (No. 49736190).  相似文献