鲁东地区旭口组与近浅海全新世沉积地层特征

山东省近浅海全新世沉积与旭口组的地层结构、纵横向变化、沉积环境是相同或相似的沉积环境中形成的相似岩石组合。旭口组的含义应扩大到浅海 ,全新世以来在浅海附近 ,海水动力作用形成的潮流砂体、潮滩、河口、砂坝、砂堤、浅滩砂等海积砂体 ,夹有少量砾石和淤泥层 。

大亚湾近岸浅海马尾藻遥感信息提取

马尾藻对健康的沿海生态系统具有重要作用。遥感监测多针对开阔海域的漂浮马尾藻,对浅海底栖型马尾藻研究较少;技术方法大多基于经验模型,依赖大量实测数据。本文基于水体辐射传输过程,建立马尾藻遥感信息提取模型。大亚湾3个试验结果表明:①马尾藻丰度分布情况与野外调查数据基本吻合;②大亚湾的马尾藻在水域开阔程度高、水体交换条件良好、受一定风浪影响、水深小于1.6 m的环境条件下,长势更好,丰度更高;③水深、海浪作用是影响马尾藻生长分布的重要环境因子。本文方法对马尾藻资源的保护和海岸带生物多样性建设具有积极意义。

近岸浅海海底输油管道施工技术

铺设海底石油管道通常采用专用船舶作业,适用于深海长距离海底管道工程。近岸海域浅水区铺设输油管道工程需另辟蹊径。本文以柬埔寨PAPA石油贡布海底输油管道工程为例,结合当地经济技术条件,着重介绍了管道陆上拼装、滑移下水、水上拖运、海上对接、配重沉放、锚碇的施工工艺与措施。工程实践表明该技术具有工艺新颖、操作安全、便捷的特点,具有较好的经济实用性。对此加以总结,以期为类似工程提供参考。

不同生境中鲈鱼肾脏显微和亚微结构变化的初步研究

鲈鱼Lateolabrax japonicus(C et V)为近岸浅海习见的广盐性鱼类喜栖息河口咸淡水处，亦可生活淡水中。海、淡两种不同盐度和渗透压必然导致肾结构及其功能的变化(M·E勃朗1962；邵炳绪1981)。但对鲈鱼肾脏的显微与亚微结构情况至今未见报道。为此本文分别取用海产和淡养两种不同生境中生长的鲈鱼肾脏，进行光镜和电镜观察、比较，并对其出现的结构变化作了初步研究。

Determination of fractional energy loss of waves in nearshore waters using an improved high-order Boussinesq-type model

Fractional energy losses of waves due to wave breaking when passing over a submerged bar are studied systematically using a modified numerical code that is based on the high-order Boussinesq-type equations.The model is first tested by the additional experimental data,and the model's capability of simulating the wave transformation over both gentle slope and steep slope is demonstrated.Then,the model's breaking index is replaced and tested.The new breaking index,which is optimized from the several breaking indices,is not sensitive to the spatial grid length and includes the bottom slopes.Numerical tests show that the modified model with the new breaking index is more stable and efficient for the shallow-water wave breaking.Finally,the modified model is used to study the fractional energy losses for the regular waves propagating and breaking over a submerged bar.Our results have revealed that how the nonlinearity and the dispersion of the incident waves as well as the dimensionless bar height(normalized by water depth) dominate the fractional energy losses.It is also found that the bar slope(limited to gentle slopes that less than 1:10) and the dimensionless bar length(normalized by incident wave length) have negligible effects on the fractional energy losses.

头比锤子硬

生活在赤道附近浅海中的撞击鱼,色彩斑斓,身体粗壮。它们整天撞击珊瑚礁,摄取珊瑚虫和梭尾螺。遇到带有硬壳的动物。