厦门海域海水对铝镁合金腐蚀的苛刻性及其电化学机理

我国不同的海域的表层海水对铝合金显示出不同的腐蚀性 ,其中 ,以厦门海域海水对铝镁合金的腐蚀最为苛刻 ,而青岛海域海水则对铝镁合金的腐蚀性最为温和 .原因即在厦门海域海水的特殊盐度以及由此产生的“电解质”效应 .文中给出了典型铝镁合金在青岛 ,厦门 ,榆林各海域全浸 ,潮差 ,飞溅区暴露 1 6a(年 )的腐蚀数据和腐蚀形貌 ,进一步证实了“电解质”效应在海洋腐蚀过程中存在的普遍性     

Spatial and temporal distribution of environmental markers from Coastal to Plateau areas in Antarctica by firn core chemical analysis

The chemical analysis of shallow firn cores sampled in coastal and plateau areas in Northern Victoria Land and along a transect from Talos Dome to Dome C (East Antarctica, Pacific Ocean sector) allowed a global view of spatial and temporal changes in chemical composition of snow depositions over the last 100 years. Variations in concentration of primary (sea spray) and secondary (biogenic emission, atmospheric inputs) source markers were observed and discussed as a function of distance from the sea and altitude.

In the stations characterized by relatively high snow accumulation rates, the sub-sampling resolution was sufficient to obtain a stratigraphic dating by using the periodical variations of seasonal markers. In these stations, a subdivision in “summer” and “winter” samples was carried out in order to study the seasonal changes of the contributions of the measured compounds to the snow composition as elevation and distance from the sea increase.

Some evidence of post-depositional effects which are able to change the original deposition of chloride and nitrate, was observed at stations with low accumulation rates. The reliability of the depth/concentration profile of these substances for reconstructing past deposition was also discussed.     

离子色谱法测定南海海水中的硝酸盐和磷酸盐及其对地球化学意义的初探

根据2010年"西太平洋海域海洋灾害对气候变化的响应"航次,从南海海域选取E断面4000m水深全层次站位,采用氧化银沉淀法,结合免化学试剂离子色谱技术分析了该站海水中的NO-3-N、PO3-4-P,NO-3、PO43-的检出限分别为4.84和17.1μg/L,回收率分别为94.5%和101.2%,相对标准偏差(RSD)分别为0.27%和0.15%,结果令人满意。并对其地球化学意义进行了初步分析探讨,为南海及周边海域海洋环境的研究提供了基础数据。     

Types of saltwater intrusion of the Changjiang Estuary

The Changjiang Estuary is characterized by multi-order bifurcations, unsteady submerged sandbars, mid-channel sandbars, creeks and riffles. The following four types of saltwater intrusion are found: (1) direct intrusion from the sea; (2) intrusion during tidal flooding; (3) intrusion from tidal flats overflow; and (4) salt water coming upstream through other waterways. These result in a complicated temporal and spatial salinity distribution. A high chlorinity concentration zone exists from the Liuhekou to the Sidongkou along the South Branch. The salinity during neap tide or ordinary tide is higher than during spring tide.     

Types of saltwater intrusion of the Changjiang Estuary

The Changjiang Estuary is characterized by multi-order bifurcations, unsteady sub-merged sandbars, mid-channel sandbars, creeks and riffles. The following four types of saltwater intrusion are found: (1) direct intrusion from the sea; (2) intrusion during tidal flooding; (3) intrusion from tidal flats overflow; and (4) salt water coming upstream through other waterways. These result in a complicated temporal and spatial salinity distribution. A high chlorinity concentration zone exists from the Liuhekou to the Sidongkou along the South Branch. The salinity during neap tide or ordinary tide is higher than during spring tide.     

METHOD OF INTEGRATED GREEN''''S FUNCTION FOR THE CALCULATION OF TILT LOAD TIDE CAUSED BY THE OCEANIC TIDES

The method of integrated Green's function for the calculation of the tilt(?)load tide proposed by this paper is sn improvement and s development of the current widely used method proposed by Farrell, and it is s new method of calculation. According to this method, the integrated Green's function of tilt load tide has been calculated first, then on the basis of the cotidal charts the tilt load tide caused by the oceanic tides at any point on the continent can be easily calculated through algebraic procedures. As an example of application of this method the tilt load tides of M_2 have been calculated on the basis of cotidal charts of Schwiderski for the following three stations: Wuchang, Tai'an and Xuzhou.     

The UV Index on the Spanish Mediterranean coast

An analysis is made of measured ultraviolet erythemal solar radiation (UVER) data recorded during the year 2003 by the networks of the Catalan Weather Service and the Environment Department of Valencia (both on the Spanish Mediterranean coast). Results show a latitudinal variation at sea level, of 3-4% per degree and an increase with altitude of 10% per km. Based on these data the UV Index has been evaluated for the measuring stations. The maximum experimental value of the UV Index was around 9 during the summer, although higher values were recorded at two stations, one at the highest elevation and the other at the lowest latitude. The annual accumulated doses of irradiation on a horizontal plane have been presented as well as the evolution through the year in units of energy, Standard Erythemal Doses and Minimum Erythemal Doses according to different phototypes. Lastly, the UV Index forecast, determined with a multiple scattering radiative transfer model, has been analyzed. Total agreement or only one unit of difference between measured and modelled values was found in 94% of cloud-free cases.     

SEDIMENTARY PROPERTIES AND ENVIRONMENTAL VARIATIONS FROM CONTINENTAL SLOPE TO DEEP SEA PLAIN IN THE NORTHERN SOUTH CHINA SEA SINCE LATE PLEISTOCENE

The South China Sea is the westernmost marginal sea in the west Pacific Ocean. On thebasis of the analyses of sedimentary components, biofossils, oxygen-carbon isotopes and theirdatings in four seafloor cores which were collected from the deep sea plain to continentalslope in the northern South China Sea, the environmental variations were basically similarto other tropical ocean areas, and their cycle changes in about the ages of 40 ka and 20 kawere more apparent since the late Pleistocene. During the warm climates, the depositionrate on the continental slope was about 2.6 times as rapid as on the deep sea plain margin.The seafloor in the deep sea plain was below the CaCO_3 compensation depth. During thecold periods, however, the deposition rate on the deep sea plain margin was slightly quickerthan on the continental slope due to the sea level reduction on a larger scale and moresupply of the terrigenous clastics.     

Principal component analysis application in polycyclic aromatic hydrocarbons “mussel watch” analyses for source identification

This article aims to show how a careful pre-treatment of data can be used to demonstrate various features embedded in a given data set obtained from a “mussel watch” survey, namely site- and source-specific characteristics and weather-related changes, and to provide indications so as to allow comparison with analyses performed on another substrate matrix. Polycyclic aromatic hydrocarbons (PAHs) biomonitored in the aquatic environment by means of caged mussels are compared by site and by season. Moreover, their fingerprints were compared to marine sediments and atmospheric airborne PAHs. The characterization of the sampling stations by means of the multivariate technique called principal component analysis (PCA) allows distinguishing the prevalence of pyrogenic or petrogenic types of pollution and between two kinds of combustibles. This was confirmed by jointly analyzing the percent composition of sea (mussel) and air (filter) samples.     

Treatment of Red Tide in Ocean Using Non-Thermal Plasma Based Advanced Oxidation Technology*

A Pilot-scale experiment for the treatment of red tide in the enclosure was done in sea area of Shandong Province, P.R. China on Aug. 25, 2002. With the method of micro-gap discharge, O₂ in air and H₂O in seawater are ionized and dissociated into large numbers of OH^• radicals, and then dissolved into a part of seawater to form OH^• solution of high concentration. With OH^• concentration of 0.68 mg/L, the kill efficiencies of 29 kinds of red tide organisms such as Chaetoceros lorenzianus and so on reached 99.89%, in which bacterium and vibrio were reduced below the detection limit, also Gonyaulax cysts and Prei. Cysts with the crust were done the lowest limit of test. At the same time, the content of chlorophyll-a was decreased below the detection limit. DO (dissolved oxygen) saturation of seawater was greatly increased to 100% because the residual OH^• radical was decomposed into H₂O and O₂ after 20 min. Therefore the treatment of red tide using OH^• radicals is a kind of advanced oxidation technology, which realizes zero pollution, zero emission and zero residual in the process of the production of OH^• radicals and the treatment of red tide.*Key project of National Foundation Research from Science and Technology Ministry of China, (2002CCC00900); key project of National Natural Science Foundation of China (NSFC; 60031001).     

Determination of dihaloacetonitriles and halophenols in chlorinated sea water

The cooling effluents in power stations are chlorinated to avoid excessive biofouling. However, this disinfecting treatment leads to the formation of halogenated by-products, mainly trihalomethanes, haloacetonitriles and halophenols. There is therefore a need for precise and accurate methods that allow trace level determinations of these compounds. Experimental procedures combining liquid-liquid extraction and gas chromatography coupled to mass spectrometry were developed in this study to determine dihaloacetonitriles and halophenols. The extraction step was improved and the performance of both methods evaluated. Precise and accurate determinations were obtained, allowing the measurement of the investigated compounds in chlorinated sea water samples from three French nuclear power stations.     

Determination of rare earth, major and trace elements in authigenic fraction of Andaman Sea (Northeastern Indian Ocean) sediments by Inductively Coupled Plasma-Mass Spectrometry

Downcore variation of rare earth elements (REEs) in the authigenic Fe-Mn oxides of a sediment core (covering a record of last ∼ 40 kyr) from the Andaman Sea, a part of the Indian Ocean shows distinctive positive Ce and Eu anomalies. These positive Ce anomalies (Ce* = 1.1 ∼ 1.8) are ascribed to be due to oxidation of deep sea sediments. The large positive Eu anomalies (i.e., Eu* >1.8 to 3.2) occur within a time span near the glacial/interglacial transition (∼ 7000-14,000 yr BP) which could be due to the past hydrothermal activity or to the effects arising from sea level changes. During glacial times, the Andaman Sea was almost completely isolated due to low sea level, leading to a reduction in sediment supply from the Ayeyarwady River. The variations of metal abundances (i.e., Ca, Al, Mn, and Fe) in the authigenic fraction provided independent information to evaluate the water column physicochemical changes during the glacial/interglacial transition period. The studied sediment core records changes in riverine inputs and reflects depositional changes related to sea level fluctuations and climatic events over the past 40 kyr in the Andaman Sea.     

Monthly sea surface temperature records reconstructed by δ~(18)O of reef-building coral in the east of Hainan Island, South China Sea

Stable oxygen isotopic compositions of a coral colony of Porites lutea obtained on acore allowed the reconstruction of a 56-a (1943-1998) proxy record of the sea surface tempera-tures. This coral δ~(18)O data are from the east of Hainan Island water (22°20＇N, 110°39＇E), SouthChina Sea. The relationship between δ~(18)O in the skeletal aragonite carbonate and the sea surfacetemperature (SST) is SST=-5.36 δ~(18)O_(PDB)-3.51 (r=0.73, n=470), dδ~(18)O/d(SST)=-0.187‰/℃; and the thermometer was set at monthly resolution. The 56-a (1943-1998) proxy record of thesea surface temperatures reflected the same change trend in the northern part of South China Seaas the air temperature change trend in China.     

Isolation of a bacterium from mangrove soil for degradation of sea sludge

Sea sludge, which is sediment of fish excrement and sewage on the sea bottom, continues to be a serious environmental problem. It has the potential to cause eutrophication and red tide, resulting in the death of shellfish and leading to an offensive odor. Soil taken from a mangrove swamp was added to sea sludge, which promoted an initial fermentation of the sludge components. This article reports on the isolation of a bacterium from mangrove soil that is involved in that fermentation. Three bacteria were isolated on a marine agar plate after incubating for 12 h at 60°C. One of these bacteria fermented sea sludge. 16S rDNA of this bacterium was sequenced, and it had a high homology with that of Bacillus fumarioli LMG17489^T (AJ250056).     

Long-term morpho-dynamics in special type of estuary

Thousands of rocky hills and islands scattered in the Pearl River delta plain and the adjacent coastal waters in South China have been or will be acted as deposition nucleus during the evolution process of the delta. The Huangmaohai estuarine complex consists of two of the eight major outlets of the Pearl River estuarine system. Since sea level reached the present level approximately 6000 years ago, especially in the last 250 years, the Huangmaohai estuarine complex has progressed to the sea by filling up the sea inlets formed between these rocky islands and between mainland and islands. This 'filling up' process left deep imprints on the long-term mor-pho-dynamic equilibrium in the estuaries. The present paper reveals that the long-term mor-pho-dynamic relation originating from this 'filling up' process in the Huangmaohai estuarine complex is different from that in many coastal plain estuaries in several aspects: (1) longitudinal variation of estuary width, (2) longitudinal variation of tidal range, (3)     

COMPARATIVE RESEARCH ON ENVIRONMENTAL EVOLUTION BETWEEN THE RECION OF ANTARCTIC GREAT WALL STATION AND CHINA

Through comparative analysis between the environmental changes in the region of KingGeorge Island in Antarctic and the characteristics of environmental evolution in the differentregions of China, the paper reveals the important similarity of the environmental evolutionbetween the two regions. The fine correspondence relations between the environmentalchanges of King George Island region in Antarctic, the glacial activities on the mountainousterrain in the western part of China, and the oscillation of the northern boundary of sub-tropical zone in the eastern part of China pointed out in this study serve as evidence to sup-port the interaction between the Northern and Southern Hemispheres. The uniformity of theclimatic changes of the King George Island region in Antarctic with the changes of sea levelof China and the world also supports the similarity of the trend of global changes in tem-perature since the Holocene. One must pay attention to the macroscopic and integrated studyof the whole earth in order     

Long-term morpho-dyn amics in special type of estuary

Thousands of rocky hills and islands scattered in the Pearl River delta plain and the adjacent coastal waters in South China have been or will be acted as deposition nucleus during the evolution process of the delta. The Huangmaohai estuarine complex consists of two of the eight major outlets of the Pearl River estuarine system. Since sea level reached the present level approximately 6000 years ago, especially in the last 250 years, the Huangmaohai estuarine complex has progressed to the sea by filling up the sea inlets formed between these rocky islands and between mainland and islands. This ‘filling up’ process left deep imprints on the long-term morpho-dynamic equilibrium in the estuaries. The present paper reveals that the long-term morpho-dynamic relation originating from this ‘filling up’ process in the Huangmaohai estuarine complex is different from that in many coastal plain estuaries in several aspects: (1) longitudinal variation of estuary width, (2) longitudinal variation of tidal range, (3) unique combination of small-scale dynamic structures, (4) bidirectional jet systems, and (5) velocity field and turbidity maximum.     

Comparison of GOME-2 UVA Satellite Data to Ground-Based UVA Measurements in South Africa

Satellite estimates of surface ultraviolet A (UVA) (315–400 nm) from the Global Ozone Monitoring Experiment (GOME)-2 were compared to ground-based measurements at four stations in South Africa for 2015. The comparison of daily exposure and daily maximum irradiance was completed for all-sky and clear-sky conditions. There is a strong linear correlation between the satellite and ground-based data with a correlation coefficient (r) between 0.86 and 0.97 for all-sky conditions. However, at three of the stations the satellite data are underestimated compared to ground-based data with a mean bias error (MBE) between −8.7% and −20.6%. A seasonal analysis indicated that there is a link between the bias in ground-based and GOME-2 UVA and cloud fraction. Factors such as aerosols, surface albedo, altitude and data resolution may contribute to the underestimations found at the three sites. These results indicate that satellite estimates of surface UVA over South Africa do not exhibit the same behavior as other stations around the world and therefore require further validation.     

Penetration of solar radiation into the waters of Messina Strait (Italy)

The optical properties of the waters of five different stations, three located in the Messina Strait and two near the Strait (open sea), were analysed. Direct spectral measurements of the downward solar irradiance (290 - 800 nm) at different depths (0.5 m, 7 m, 10 m, 13 m, 20 m) were made using a cosine sensor connected to a spectroradiometer. Water samples were collected in the surface layer and their absorption spectra were analysed. The natural fluorescence profiles, along the water column, were determined using a fluorometer (SBE 911plus - Sea Teach). The spectral attenuation coefficient (K(lambda)), the variation of K(lambda) in different wavelength ranges (deltaK(deltalambda)), the wavelength corresponding to minimum value of K(lambda), the spectral depths of penetration of both 1% and 10% of the sub-surface irradiance values (P(lambda)), the depths of 1% of penetration of UVB, UVA and PAR, the depth ranges of the maxim concentration of Chl a and superficial CDOM were measured at each station. The maximum solar UVB penetration was about 65% of the photic zone and the maximum UVA penetration was nearly 100% (data of the Ionic sea station). Thus, a large part of the photic zone was exposed to UV radiation sufficient to cause a possible reduction in the photosynthetic activity of phytoplankton. The spectral penetration of solar radiation, especially UVB radiation, was significantly different in the three stations of the Strait with respect to the two stations studied in the open sea. This shows that variations in the spectral attenuation along the water column can be used as an indicator of properties of the water body.     

CLAY MINERALS IN THE CHINA SEA AND ADJACENT SEAS

The clay minerals in the surface sediments from 354 stations have been analyzed qualita-tively and semiquantitatively. The obtained data are dealt mathematically. According to thecalculated results, the distribution laws and the trends of content changes of clay mineralsare discussed. The studied area is divided into four main provinces of sediments with differ-ent sources. Finally the author approached the laws of the migration and dispersal of thefine-grained matter carried into the seas by the Huanghe River, the Changjiang River, theZhujiang River and the Philippine Archipelagoes, and set up the transport model of the fine-grained matter in the China Sea and adjacent seas.