Dissolved inorganic carbon and CO2 fluxes across Jiaozhou Bay air-water interface

On the basis of data collected in the Jiaozhou Bay in June and July 2003, the DIC distribution in seawater is studied,and an average air-sea flux of CO2 is estimated. The results show that the content of DIC inside the bay is markedly higher than outside the bay in June, but the content of DIC outside the bay is markedly higher than inside the bay in July. The trend of DIC distribution inside the bay is similar, viz. the content is the maximum in the northeast, then decreases gradually toward the west, and the content is the minimum in the west. The total trend of vertical distribution is to increase gradually from surface to bottom. This characteristic of DIC distribution is determined by Jiaozhou Bay hydrology and there is a close relation between DIC and particulate N,P. Average CO2 flux across the source for atmospheric CO2 in June and July, and the total CO2 flux from seawater into atmosphere is about 740 t in June and 969 t in July.     

Dissolved inorganic carbon and CO2 fluxes across Jiaozhou Bay air-water interface

On the basis of data collected in the Jiaozhou Bay in June and July 2003, the DIC distribution in seawater is studied,and an average air-sea flux of CO2 is estimated. The results show that the content of DIC inside the bay is markedly higher than outside the bay in June, but the contem of DIC outside the bay is markedly higher than inside the bay in July. The trend of DIC distribution inside the bay is similar, viz. the content is the maximum in the northeast, then decreases gradually toward the west, and the content is the minimum in the west. The total trend of vertical distribution is to increase gradually from surface to bottom. This characteristic of DIC distribution is determined by Jiaozhou Bay hydrology and there is a close relation between DIC and particulate N.P. Average CO2 flux across the air-sea interface is 0.55 mol/(m^2.a) in June and 0.72 mol/(m^2.a) in July. Jiaozhou Bay is considered as a net annual source for atmospheric CO2 in June and July, and the total CO2 flux from seawater into atmosphere is about 740 t in June and 969 t in July.     

广州市地面沉降危险性评价

地面沉降是珠江三角洲主要城市地质灾害之一,广州市尤为严重。在GIS技术和基础地理信息数据库的支持下,采用模糊数学层次分析法(AHP)和相应的指标体系对广州市地面沉降危险性进行了评价。广州市主城区地面沉降危险性可分为5个等级,极不稳定级主要分布在珠江沿岸和珠江环绕地区;不稳定级主要分布在北部和东北部部分地段;次不稳定级主要分布在西北角和西南角;基本稳定级分布零散,东部、西部均有所见;稳定级分布在北部和东部的外围地带。     

北黄海及渤海变性水团的初步分析

根据1978—1980年渤海及北黄海70个测站的表、底层温、盐资料,用预先给定控制临界值的聚类方法,在该海域划分出5个水团。分析结果表明。1.渤黄海暧水团在冬季为高盐特征,夏季为中盐性质;其分布范围在冬—春季较小而夏—秋季较大。2.渤海水团为中温中盐性质:其温、盐度变化较小而冬—春季范围较大。3.黄海冷水团是一个高盐水团,它在5个水团中保守性最强,而从5月至8月范围较大。4.渤海沿岸水是一个不稳定的水团,其盐度较低,温度变化较小,春季和秋季范围较大而夏季和冬季较小。5.江河冲淡水是温度变化较大的低盐水,其范围夏季大而冬季小。水团的分布,在地理位置上是从该海区之东向西,一层套一层,而各水团在不同季节有自己的模式。此外,本文还探讨了水团消长变化和渔场的关系。     

北黄海温盐分布季节变化特征分析

利用2006～2007年夏冬春秋4个季节北黄海的大面调查资料,分析了4个季节北黄海温度和盐度大面以及典型断面分布特征,得出以下结论:2007年冷水团势力范围强于2006年,北黄海冷水团的形成受地形影响.黄海暖流冬春季较强,冬季最强,夏季最弱,秋季开始形成.鲁北沿岸流冬季最强,春季减弱,夏秋季消失,但夏季鲁北沿岸存在冬季鲁北沿岸流水的残余体,即鲁北沿岸水.辽南沿岸水4个季节都以低盐为特征,除夏季低盐中心位于庄河口外,其它3个季节低盐中心均位于调查区域的东北角.渤海与北黄海之间的水交换4个季节都存在.春季,断面盐跃层形成滞后于温跃层;秋季,断面盐跃层消失滞后于温跃层.     

Sea surface height anomaly and geostrophic circulation variations in the South China Sea from TOPEX/POSEIDON altimetry

The sea surface height anomaly (SSHA) and geostrophic circulation in the South ChinaSea (SCS) are studied using TOPEX/POSE1DON (T/P) altimetry data. The SSHA, which is obtained after tidal correction based on the tidal results from T/P data, is predominated by seasonal alternating monsoons. The results reveal that the SSHA in the central part of the SCS is positive in spring and summer, but negative in autumn and winter. It is also found that the SSHA in the SCS can be approached with the sum of tidal constituents SA and SSA. The geostrophic circulations in the SCS are calculated according to sea surface dynamic topography, which is the sum of SSHA and mean sea surface height. It is suggested that the circulation in the upper layer of the SCS is generally cyclonic and notably western intensified during autumn and winter, while the western intensification is weak during spring and summer. It is also indicated that the Kuroshio intrudes into the northeastern SCS throuth the Luzon Strait in winter. But ther     

胶州湾水域重金属铬的分布及迁移

根据1979年的胶州湾水域调查资料,分析了重金属铬在胶州湾水域的分布、迁移和季节变化。研究结果表明;春季,胶州湾水城铬污染较轻,大部分海域水质状况较好,而到夏季没有受到污染。在时空分布上,春季,铬污染形成了明显的梯度,由东北向西南方向递减,从112．3μg／L降低到0．2μg／L。夏季,铬的水平分布比较均匀,表层水体铬的含量较低,范围在0．10～1．40μg／L之间波动。因此认为,1979年整个胶州湾水域的重金属铬属于面污染源。而且,当铬进入胶州湾海域后,很快吸附在水体中的悬浮颗粒上,并被水流较快地带离胶州湾水城,几乎没有在胶州湾水域表、底层留下污染痕迹。     

Effect of waves on cavitation and pressure pulses of a tanker with twin podded propulsion

There is increasing interest in optimizing ships for the actual operating condition rather than just for calm water. In order to optimize the propeller designs for operations in waves, it is essential to study how the propeller performance is affected by operation in waves. The effect of various factors that influence the propeller is quantified in this paper using a 8000 dwt chemical tanker equipped with twin-podded propulsion as a case vessel. Propeller performance in waves in terms of cavitation, pressure pulses, and efficiency is compared with the performance in calm water. The influence of wake variation, ship motions, RPM fluctuations and speed loss is studied. Substantial increase in cavitation and pressure pulses due to wake variation in the presence of waves is found. It is found that the effect of other factors is relatively small and easier to take into account as compared to wake variation. Therefore, considering the wake variation at least in the critical wave condition (where the wavelength is close to ship length) in addition to calm water wake is recommended in order to ensure that the optimized propeller performs well both in calm water and in waves.     

江苏省主要湖泊的降水量与湖泊的降水效应

本文分析了江苏境内主要湖泊的降水量特征,揭示了长江是江苏各湖泊不同降水量特征的一条十分明显的天然界线;估算了太湖的降水效应,并据此推估出江苏主要湖泊的降水效应不太明显;江苏各湖泊的降水量与其水位年过程趋势相似,只是后者位相滞后于前者而已。     

SMAP卫星海表盐度产品精度评定与全球海表盐度特征分析

海表盐度是研究海洋变化及其气候效应重要的物理量。本文将2018年SMAP卫星的月均、日均海表盐度产品分别与Argo月均网格化产品、实时散点盐度数据进行比较,评定其精度,并分析全球海表盐度分布特征。结果表明：SMAP卫星月均产品RMSE为0.17,BIAS为0.11,STD为0.17,R为0.98,t检验呈显著相关;SMAP卫星日均产品RMSE为0.28,BIAS为0.23,STD为0.26,R为0.81,相较月均产品,精度较低。SMAP卫星月均产品偏差在中纬度海域较小,在高纬度海域较大;SMAP卫星日均产品偏差在太平洋海域为-0.6~0.6,在地中海海域超过1.0。全球海表盐度在25.0~40.0之间,沿纬度方向呈带状分布,其中大西洋海表盐度普遍高于太平洋和印度洋。     

海底输水管道敷设过程中悬浮泥沙对海洋环境影响的数值研究

海底管道敷设过程中产生的悬浮泥沙会对工程海域的水质和海洋生物造成影响.建立了2D悬浮泥沙输移模型,结合水动力模型,对舟山市临城至虾峙岛、六横岛输配水工程中海底管线敷设引起的悬浮泥沙的输移规律进行模拟研究,预测悬浮泥沙的影响程度和范围,为海洋环境影响评价提供依据.计算结果表明:1号工段管道敷设对海水水质影响最大,2号工段...     

Impacts of a wind stress and a buoyancy flux on the seasonal variation of mixing layer depth in the South China Sea

The seasonal variation of mixing layer depth(MLD) in the ocean is determined by a wind stress and a buoyance flux.A South China Sea(SCS) ocean data assimilation system is used to analyze the seasonal cycle of its MLD.It is found that the variability of MLD in the SCS is shallow in summer and deep in winter,as is the case in general.Owing to local atmosphere forcing and ocean dynamics,the seasonal variability shows a regional characteristic in the SCS.In the northern SCS,the MLD is shallow in summer and deep in winter,affected coherently by the wind stress and the buoyance flux.The variation of MLD in the west is close to that in the central SCS,influenced by the advection of strong western boundary currents.The eastern SCS presents an annual cycle,which is deep in summer and shallow in winter,primarily impacted by a heat flux on the air-sea interface.So regional characteristic needs to be cared in the analysis about the MLD of SCS.     

东海沿岸海区垂直环流及其温盐结构动力过程研究I．环流的基本特征

利用三维斜压流体动力学模型 ,通过对东海沿岸海区冬、夏季的斜压环流及其温盐结构的数值研究 ,揭示研究海区垂直环流及其温盐结构的动力过程及其成因。垂直环流的模拟结果表明 :冬季 ,沿岸海区的垂直环流以逆时针流动 ,近表层为向岸流 ,沿岸为下降流 ,近表层以下为离岸流 ,其在外海有明显的上升趋势 ,沿岸下降流自表层至底层逐渐由强变弱 ;夏季 ,沿岸海区的垂直环流以顺时针流动 ,近表层以下为向岸流 ,沿岸为上升流 ,近表层为离岸流 ,其在外海有明显的下降趋势 ,沿岸上升流自底层至表层逐渐由弱变强。就整个沿岸海区而论 ,冬季沿岸下降流和夏季沿岸上升流的强度都随着岸界地形坡度、风速及风向与岸线偏角的变化而变化。沿岸下降流形成的主要原因是由于冬季东北风与岸界地形的耦合效应及海区温盐分布不均匀所致 ,而沿岸上升流形成的主要原因则是由于夏季西南风与岸界地形的耦合效应及海区温盐分布不均匀所致。     

黄岛电厂取水工程潮流泥沙数值模拟

建立了基于不规则三角形网格的考虑波浪及其破碎作用的二维潮流场和泥沙场数学模型,对黄岛电厂取水海域的潮流场、泥沙场进行了数值模拟和分析,对电厂取水口的泥淤积强度进行了计算。计算结果表明,电厂取水口附近海区流弱水清,取水口泥沙淤积轻微,对电厂取水基本没有影响。     

河北滦南滨海湿地土壤重金属污染特征及评价

滨海湿地作为一种具有多种功能和蕴含丰富资源的生态系统，是人类重要的生存环境之一。湿地土壤重金属污染问题是当前湿地科学领域内的热点话题。为研究河北省滦南滨海湿地重金属污染特征，本文利用单因子指数法、内梅罗综合污染指数法和地累积指数法对重金属污染状况进行评价。结果表明：铜（Cu）、锌（Zn）、铬（Cr）、铅（Pb）、镉（Cd） 的单因子质量指数均小于1.0，说明研究区重金属含量小于土壤背景值，土壤未受到污染。内梅罗综合指数法Cu、Zn、Cr、Pb、Cd 指数均小于0.7，表明滦南湿地土壤重金属污染水平处于未污染。湿地各区域重金属地累积指数为无污染或较轻污染，其中Pb 污染为较轻污染，监测点主要与人类活动有关。利用地累积指数分析认为Pb 在湿地北区为轻度污染水平，经调查发现该区域主要为居民点，人类活动频繁，其他重金属均无污染。河北滦南滨河湿地土壤未受到重金属污染，湿地土壤环境较好。     

大亚湾和大鹏湾两个相邻海湾潮波浅水变形的异同分析

利用实测资料分析重构了大亚湾和大鹏湾潮汐水位“双峰”现象,确定了浅水分潮的异常增长是潮位“双峰”现象的主要成因,其中四分之一日分潮和六分之一日分潮起着至关重要的作用。通过SCHISM模型构建大亚湾和大鹏湾附近海域高分辨率水动力模型,模拟结果表明近岸海域,在大亚湾以东,潮汐类型为不规则全日潮,以西为不规则半日潮,在两个海湾内均为不规则半日潮;研究海域的潮流均表现为不规则半日潮流。四分之一日分潮和六分之一日分潮在大亚湾和大鹏湾的不同变形过程是造成两个相邻海湾水文差异的直接原因。通过构建不同底摩擦强度、消除水底地形以及改变海湾水深的数值实验研究表明,分潮传播方向与水深变浅方向是否一致,是导致两个海湾潮波浅水变形不同的根本原因。     

豪华邮轮耐波性及救生艇砰击载荷特性研究

利用基于三维势流理论的Wasim软件,系统研究了在不同海况下大型豪华邮轮的耐波性能及作用在救生艇上的砰击载荷。首先计算豪华邮轮在规则波和不规则波中的运动响应,分析航速、浪向和海况对豪华邮轮运动响应的影响规律,然后计算救生艇在不同海况下砰击载荷的变化规律,根据变化规律评估救生艇在实际航行中的安全性。结果表明：豪华邮轮运动响应幅值随着航速和海况的增大整体呈增大趋势,规则波中横摇运动响应幅值在浪向90°时最大;当豪华邮轮处于4级和6级海况时救生艇不发生砰击;当豪华邮轮处于8级海况且航速大于10.29 m/s时救生艇发生砰击,为保证救生艇的安全,邮轮应避免在浪向120°和浪向150°下航行,此时建议邮轮以低于12.35 m/s的航速迎浪180°航行。     

多波束测深趋势面系数的主成分估计

在多波束测深趋势面滤波构建趋势面模型的过程中,其模型变量线性相关时,系数阵存在复共线性,因此将主成分估计的方法应用于趋势面模型系数的求解,从而避免了复共线性的影响,最后通过实测数据进行实验,分别利用最小二乘算法和主成分估计求解二次趋势面模型。比较计算结果,验证了主成分估计算法的有效性。     

基于TRMM观测的亚洲——太平洋三个季风区的降水结构特征

The three-dimensional structure of precipitation on a seasonal scale in the Asian-Pacific＇s three monsoon regions is investigated based on the tropical rainfall measurement mission （TRMM） data. The results show that： （1） The maximum seasonal variation of the relative proportional difference of convective precipitation and stratiform rain occurs in the East Asian monsoon region, the second occurs in the Indian monsoon region, and the minimum is in the northwest Pacific monsoon region. In both the northwest Pacific mon soon region and the Indian monsoon region, the convective rain is proportionately larger than stratiform rain in all four seasons. （2） Cloud ice reaches its maximum at around 9 km. Cloud water＇s maximum range is between 3 and 4 km. The large value area of precipitation ice is mainly between 4 and 9 km. The precipi tation water particle is concentrated mostly below 4 km. The largest content is from the ground to 2 km. （3） The most remarkable variance of the content of cloud ice in the Indian monsoon region occurs from spring to winter, and the content of cloud water in the northwest Pacific is always higher than that in the other two regions. （4） The latent heat profile has a similar double-peak structure. The first peak is at 4 km and the second peak is at 2 km. In autumn and winter, the latent heat is higher in the northwest Pacific than in other two regions. In all three regions, the release of the latent heat is higher in summer and autumn than in spring and winter.     

几种海洋生物体内硒含量的测定

本文用石墨炉原子吸收光谱法直接测定几种海洋生物体内的硒含量。本方法的最低检出限为３０ｐｇ，变异系数低于５．９％，回收率９４％－９９％。测定发现；褐藻含硒量比红藻和绿藻低，紫贻贝和海湾扇贝的外套膜中硒含量远远高于肌肉组织。