广利河口拦门沙发育动态和河口航道的选择

根据现场调查和历史资料,获取了广利河口拦门沙水动力特征、海底地形和底质特征,对拦门沙的动态发育和波浪作用下拦门沙运动状态进行了分析,探讨了广利河口的航道选择方案。分析结果认为,广利河槽外航道宜从东偏南向入海。     

The Current System in the Yellow and East China Seas

During the 1990s, our knowledge and understanding of the current system in the Yellow and East China Seas have grown significantly due primarily to new technologies for measuring surface currents and making high-resolution three-dimensional numerical model calculations. One of the most important new findings in this decade is direct evidence of the northward current west of Kyushu provided by satellite-tracked surface drifters. In the East China Sea shelf region, these recent studies indicate that in winter the Tsushima Warm Current has a single source, the Kuroshio Branch Current in the west of Kyushu, which transports a mixture of Kuroshio Water and Changjiang River Diluted Water northward. In summer the surface Tsushima Warm Current has multiple sources, i.e., the Taiwan Warm Current, the Kuroshio Branch Current to the north of Taiwan, and the Kuroshio Branch Current west of Kyushu. The summer surface circulation pattern in the East China Sea shelf region changes year-to-year corresponding to interannual variations in Changjiang River discharge. Questions concerning the Yellow Sea Warm Current, the Chinese Coastal Current in the Yellow Sea, the current field southwest of Kyushu, and the deep circulation in the Okinawa Trough remain to be addressed in the next decade. This revised version was published online in August 2006 with corrections to the Cover Date.     

鸭绿江洪季的河口最大混浊带

对 1 994年 8月在鸭绿江河口的水文和悬浮泥沙的观测资料进行分析。结果表明 ,在洪季鸭绿江河口的最大混浊带 ,出现在第一个河口锋面内侧。它的核心处盐度小于 1 ,从上游带入河口的细颗粒泥沙多数被河口第一锋面截留 ,还有一部分上游来沙穿过该锋面 ,聚集在河口第一和第二锋面之间。垂向密度环流作用和絮凝作用在鸭绿江洪季最大混浊带的维持过程中起着主导作用     

Calanoid copepods assemblages in Pearl River Estuary of China in summer: Relationships between species distribution and environmental variables

To study the relationships between species distribution and environmental variables, calanoid copepods were classified and enumerated, and environmental variables were analyzed along 91 sites of the Pearl River Estuary (China) and adjacent waters. The 91 sites were divided into 3 groups based on surface salinity: the Inner area had salinity level below 10‰ and was mostly located in the Pearl River Estuary, the Coastal area had salinity between 10‰ and 32‰ and was almost located along the coastline, while the Offshore area had salinity level higher than 32‰ and was mainly located in the open area. Indicator Species Analysis was conducted to identify the indicator species within each group from among all calanoid copepods taxa. We found that the Inner area was characterized by Acartiella sinensis, Pseudodiaptomus poplesia and Pseudodiaptomus inopinus, the coastal area was characterized by Temora turbinata and Subeucalanus subcrassus, and the Offshore area was characterized by Paracandacia truncata, Subeucalanus subtenuis, Euchaeta rimana, Pareucalanus attenuatus, Rhincalanus cornutus, Cosmocalanus darwini, Centropages gracilis, Undinula vulgaris, Nannocalanus minor and Paraeuchaeta russelli. Canonical Correspondence Analysis (CCA) was used to identify relevant biotic and abiotic parameters that can best explain the distribution of calanoid copepods. CCA showed that during the summer of 2006, salinity, nutrient variables, especially SiO₃–Si, NO₃–N and DTN, Depth and Chl a were the environmental variables that strongly impacted the distribution and community structure of calanoid copepods.     

长江口表层沉积物中正构烷烃的高分辨分布特征及有机碳来源解析

于2014年3月对长江口及邻近海域的表层沉积物进行了高分辨率采样,分析了沉积物粒级组成、比表面积、总有机碳含量及其稳定碳同位素组成(δ¹³C)、正构烷烃及其相关分子指标,讨论了此区域沉积有机碳和正构烷烃的高分辨分布特征,并结合基于主成分分析-蒙特卡洛模拟的三端元混合模型,对沉积有机碳的来源进行了定量解析。结果表明,长江口及其邻近海域表层沉积物中总有机碳含量为0.45%±0.16%,近岸泥质区总有机碳含量较高,外海砂质区含量较低。总正构烷烃(C₁₄-C₃₅)的绝对含量和相对于总有机碳的含量分别为(1.42±0.73)μg/g和(0.34±0.21) mg/g。泥质区以长链正构烷烃占优势,具有较强的奇碳优势;砂质区以短链正构烷烃占优势,且具有一定的偶碳优势。长江输入、老黄河口输入、闽浙沿岸小型河流输入和水动力分选等因素制约了正构烷烃的输运和分布特征。模型结果显示此区域沉积有机碳来自海源、土壤和高等植物的混合输入,其中以海源为主,其贡献为42.70%±18.18%,由陆地向外海贡献逐渐升高,其次是土壤和高等植物,其贡献分别为2...     

粉质土海底边界层动态演化过程波浪水槽实验

The objectives of this study are carried out a series of controlled large wave flume experiments using fine-grained sediment from the Huanghe River Delta, exploring the complete sequence of sediment behavior in the bottom boundary layer(BBL) during wave-induced liquefaction. The results show that:(1) The BBL in silty seabed is exposed to a progressive wave, goes through a number of different stages including compaction before liquefaction, sediment liquefaction, and compaction after liquefaction, which determines the range and thickness of BBL.(2) With the introduction of waves, first, the sediment surface has settled by an amount S(S=1–2 cm) in the course of wave loadings with an insufficient accumulation of pore water pressure. And a thin high concentration layer formed the near-bed bottom.(3) Once the liquefaction sets in, the liquefied sediment with an ‘orbital motion' and the sub-liquefied sediment form a two-layer-sediment region. The range of BBL extends downwards and stopped at a certain depth, subsequently, develops upwards with the compaction process. Meanwhile, resuspended sediments diffuse to the upper water column.(4) During the dynamics process of the BBL beneath progressive waves, the re-suspended sediment increment ranked as sediment liquefaction erosion before liquefaction compaction after liquefaction.     

大沽河地下咸淡水过渡带的水-岩作用模拟

大沽河是青岛市最大的地下水源地,过量开采导致严重的地下咸水入侵,研究地下咸-淡水的地球化学作用对于地下咸水的治理具有重要的指导作用。本文选取大沽河地下咸淡水过渡带作为研究区,在地下水动态监测的基础上,通过地下水水质和含水介质矿物分析,借助当前成熟的水文地球化学模拟软件—PHREEQC 2.0,计算地下水中主要离子和络合离子的含量,定量确定矿物的饱和指数和地下水流向上矿物相与水之间的物质交换量。研究结果表明:(1)地下水中钠、钾、镁、钙主要以单一离子形态存在,硫、碳主要以络阴离子形态存在,而硅和铝主要以络合物形态存在;(2)在地下水流动路径上,方解石、白云石、伊利石、高岭土处于过饱和状态;而石膏、CO2、氯化钠、萤石、玉髓处于不饱和状态;(3)咸淡水过渡带地下水化学类型由HCO3-Ca·Na型水向Cl-Na型水转变的趋势。     

基于氮稳定同位素的九龙江口鱼类营养级研究

采用氮稳定同位素技术对2013年6—8月九龙江口采集到的隶属于13目42科61属共71种鱼类的营养级进行研究。结果表明,九龙江口鱼类的δ15 N值跨度较大,介于7.23‰~14.66‰之间。以菲律宾蛤仔(Ruditapes philippinarum)为基准生物估算出鱼类的营养级介于1.70~3.89之间,营养级最低与最高的鱼类分别为少牙斑鲆(Pseudorhombus oligodon)与多鳞鱚(Sillago sihama)。与Fishbase同种鱼类的营养级数据进行比较,83.1%的鱼类的营养级均值处于Fishbase同种鱼类的营养级范围内,但81.7%的鱼类的营养级均值比Fishbase同种鱼类的营养级均值略低;与传统的胃含物分析结果比较,58.3%的鱼类的营养级在0.5个营养级的误差范围内。基于氮稳定同位素估算的鱼类营养级较低的原因可能与本研究样品中低龄鱼及幼鱼比例较大有关。与其他方法相比,稳定同位素法在研究体型较小的幼鱼和低龄鱼营养级更具优势。鱼类营养级随其个体大小的变化明显,但存在种的差异性:不同体长的髭缟鰕虎鱼(Tridentiger barbatus)和绿鳍鱼(Chelidonichthys kumu)的营养级跨度较大,分别为1.54和1.43;而鳓(Ilisha elongata)等的营养级则跨度较小,这可能与不同鱼类的食性变化有关。     

人类活动对海洋生态系统影响的空间量化评价——以莱州湾海域为例

本文针对海域管理中难以量化人类活动对海洋生态系统影响的问题,提出人海关系空间量化模型,通过完善概念模型、构建指标体系、确定权重及标准,最终利用作用强度和位置关系量化人类活动对海洋生态系统的影响,数值在0—1之间,等分为四个影响程度,由弱到强依次为微弱、中等、强烈和极强,并将该模型和量化方法应用于莱州湾海域。研究结果表明:整个莱州湾受人类活动的综合影响均值为0.425,处于中等影响程度;其中污水排放、围填海工程及港口航运是对莱州湾生态系统影响比较强烈的人类活动;研究海域中40%受到人类活动的强烈影响,44%为中等影响,16%为微弱影响。空间量化分析显示,人类活动对莱州湾近岸海域的综合影响比邻近外海强烈,其中影响较强烈的区域出现在西南近岸海区,而影响较微弱的海区则为莱州湾北部外海。该方法空间量化结果与莱州湾实际情况相符,说明人海关系空间量化模型适合定量化评估人类活动对该海域生态系统的影响,可为"山东半岛蓝色经济区"海域管理提供技术支持。     

珠江三角洲地质灾害的模糊综合评价

珠江三角洲地质灾害种类的多样性与其所处的复杂地质环境和多变的气候条件密切相关。文章选用了地震活动、活动断裂、地壳升降运动、软土地基、地面塌陷以及冲、淤积等６个主要因素作为评价指标，并用模糊数学方法对珠江三角洲内１７个小区作了计算，结果表明该区大部分地区属于轻灾害区，只有滨海沿岸地区属于较重灾害区。