scholarly journals Interaction between Groundwater and Surface Water / Sea Water

2001 ◽  
Vol 43 (1) ◽  
pp. 41-42
Author(s):  
Makoto TANIGUCHI ◽  
Hiroyuki TOSAKA
Keyword(s):  
Radiocarbon ◽  
1980 ◽  
Vol 22 (3) ◽  
pp. 684-692 ◽  
Author(s):  
Georgette Delibrias

14C measurements were carried out on sea water samples collected in 1973, in the Indian ocean. The results obtained for 9 vertical profiles between 27° S and 48°S are presented. In surface water, the bomb 14C content is maximum at middle latitudes. A time lag relative to the north hemisphere bomb 14C delivery is apparent. In the more southern latitudes, 14C content remains very low.


1988 ◽  
Vol 25 (5) ◽  
pp. 701-709 ◽  
Author(s):  
A. E. Aksu ◽  
G. Vilks

Oxygen and carbon isotopic analyses have been performed on the tests of Planulina wuellerstorfi and three size fractions of sinistral Neogloboquadrina pachyderma recovered from 33 Arctic Ocean surface-sediment samples. Stable isotopic compositions of N. pachyderma are found to be dependent on the test size: larger specimens show considerable enrichment in both δ18O and δ18C. The difference between the isotopic compositions of the 63–125 and 125–250 μm size fractions in N. pachyderma can be explained by biogenic fractionation effects during foraminiferal test growth. Larger (250–500 μm) N. pachyderma displayed accretions of secondary calcite, i.e., the outermost shell contained significant amounts of inorganically precipitated magnesium calcite. Thus, larger foraminifera may not be suited for down-core stable isotopic studies. There is a difference of ~2‰ between δ18O values of surface samples from the eastern and western Arctic Ocean, reflecting large differences between surface-water salinity in these regions. Therefore, oxygen isotopic data may have limited use as a chronostratigraphic tool in down-core studies in the Arctic Ocean, but we can use them to infer past variations in surface-water salinities. Planulina wuellerstorfi also showed depletions of both δ18O and δ18C in its calcite tests relative to calcite precipitated in isotopic equilibrium with ambient sea water; these depletions ranged from −0.8 to −0.9‰ in δ18Oand −1.2 to −0.9‰ in δ18C. This taxon is found to deposit its shell very close to the δ18C of ΣCO2 of bottom waters.


1957 ◽  
Vol 8 (4) ◽  
pp. 369 ◽  
Author(s):  
DJ Rochford

In this paper an examination of all available data on the hydrological characteristics of the Tasman Sea, prior to and including the year 1954, has permitted the identification and naming of eight surface water masses. Certain of their properties and general features of their season and region of occurrence and method of formation are summarized. Although little quantitative data are available some general features of the circulation of these water masses in the Tasman Sea are deduced from a study of their seasonal occurrence in relation to source regions. The Coral Sea water mass (chlorinity 19.60-19.70‰, temperature 20-26� C) flows from a source region in the north-west Coral Sea along the western side of the Tasman Sea and reaches maximum velocity off Sydney in October-December. The South Equatorial (chlorinity 19.50-19.60‰, temperature 24-26� C) also flows south along the western side of the Tasman Sea but reaches maximum velocity between February and March. These two water masses constitute the East Australian current. The Sub-Antarctic (chlorinity 19.15-19.30‰, temperature 10-14°C) is found at the surface in the south-eastern Tasman Sea between July and September. The Central Tasman (chlorinity 19.65-19.75‰, temperature 15-20‰C) flows to the west from its region of formation and generally flows north along the southern New South Wales coast in late winter. The South-west Tasman (chlorinity 19.50- 19.60‰, temperature 12-15°C) flows to the east in latitude 38�S. and curves south in a clockwise gyral off eastern Tasmania between October and December. The Xorth Bass Strait (chlorinity 19.66-19.75‰ temperature 12-17�C) flows from South Australia to the eastern approaches of Bass Strait. The East Central New Zealand (chlorinity 19.10-19.30‰, temperature 15-20°C) flows west through Cook Strait into the Tasman Sea in midsummer. The East and West Tasmanian (chlorinity 19.40- 19.50‰ temperature 10-14°C) form in midwinter in the southern part of Bass Strait and flow along the east and west coasts in the spring.


2020 ◽  
Vol 11 ◽  
Author(s):  
Lijuan Yan ◽  
Nan Hui ◽  
Suvi Simpanen ◽  
Laura Tudeer ◽  
Martin Romantschuk

The brackish Baltic Sea is under diesel oil pollution risk due to heavy ship traffic. The situation is exasperated by densely distributed marinas and a vigorous although seasonal recreational boating. The seasonality and physical environmental variations hamper the monitoring of microbial communities in response to diesel oil spills. Hence, an 8-week simulation experiment was established in metal basins (containing 265 L sea water and 18 kg quartz sand or natural shore sand as the littoral sediment) to study the effect of accidental diesel oil spills on microbial communities. Our results demonstrated that microbial communities in the surface water responded to diesel oil contamination, whereas those in the littoral sediment did not, indicating that diesel oil degradation mainly happened in the water. Diesel oil decreased the abundance of bacteria and fungi, but increased bacterial diversity in the water. Time was the predominant driver of microbial succession, attributable to the adaption strategies of microbes. Bacteria were more sensitive to diesel oil contamination than fungi and archaea. Diesel oil increased relative abundances of bacterial phyla, Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Flavobacteriia and Cytophagia, and fungal phylum Ascomycota in the surface water. Overall, this study improves the understanding of the immediate ecological impact of accidental diesel oil contamination, providing insights into risk management at the coastal area.


1975 ◽  
Vol 32 (8) ◽  
pp. 1275-1281 ◽  
Author(s):  
William R. Penrose ◽  
Robert Black ◽  
Michael J. Hayward

Moreton’s Harbour, Newfoundland, has been exposed to arsenic-bearing drainage and leaching from a stibnite mine for at least 38 yr and possibly longer than 84 yr. Measurements of inorganic arsenic in sea water and sediments and total arsenic in some marine organisms revealed a very limited influence of continuous exposure to arsenic in the small harbor. Arsenic concentrations in surface water declined to normal within 200 m, and in sediments within 50 m. Animals did not show significantly higher levels nearer the mine, with the exception of the sea urchin Strongylocentrotus droebachiensis, which accumulated significantly higher levels of arsenic adjacent to the mine site.


2009 ◽  
Vol 6 (5) ◽  
pp. 416 ◽  
Author(s):  
Itay J. Reznik ◽  
Jiwchar Ganor ◽  
Assaf Gal ◽  
Ittai Gavrieli

Environmental context. Since the 1960s the Dead Sea water level has dropped by nearly 30 m and over the last decade the rate of decline accelerated to over 1 m per year. Conveying seawater to the Dead Sea to stabilise or even raise its water level is currently being considered but may result in ‘whitening’ of the surface water through the formation of minute gypsum crystals that will remain suspended in the water column for a prolonged period of time. This paper is a first step in attaining the relevant physical and chemical parameters required to assess the potential for such whitening of the Dead Sea. Abstract. Introduction of seawater to the Dead Sea (DS) to stabilise its level raises paramount environmental questions. A major concern is that massive nucleation and growth of minute gypsum crystals will occur as a result of mixing between the SO42–-rich Red Sea (RS) water and Ca2+-rich DS brine. If the gypsum will not settle quickly to the bottom it may influence the general appearance of the DS by ‘whitening’ the surface water. Experimental observations and theoretical calculations of degrees of saturation with respect to gypsum (DSG) and gypsum precipitation potentials (PPT) were found to agree well, over the large range but overall high ionic strength of DS–RS mixtures. The dependency of both DSG and PPT on temperature was examined as well. Based on our thermodynamic insights, slow discharge of seawater to the DS will result in a relatively saline upper water column which will lead to enhanced gypsum precipitation.


Author(s):  
W. R. G. Atkins

1. Measurements of hydrogen ion concentration, of phosphate concentration, and of temperature all show at certain seasons a well-marked gradient from surface to bottom. The upper 10–20 metres is more alkaline, notably depleted of phosphates and warmer.2. Settled summer weather and deep water, free from irregularities of the bottom, favour the formation of such a gradient. Its breaking up is occasioned by wave action and the cooling of the surface water in autumn.3. Thermal stratification in the English Channel arises at each station, and is not due to the inflow of warm over colder water.


Author(s):  
Kazuyuki Ouchi ◽  
Sadayuki Jitsuhara ◽  
Takayuki Watanabe

DOW (Deep Ocean Water: The sea water below 200m depth) which has three major characteristics, Low Temperature, Rich Nutrient and Very Clean, is expected as a future renewable resources in the ocean. Toward the era of environment and low carbon, utilizing the ocean renewable resource is absolutely important because the land base resources are now peaking out. In order to making use of DOW effectively and economically, multi-purpose utilizing of DOW is recommended because it has many aspects of characteristics and advantages. First, Electric Power generation by OTEC (Ocean Thermal Energy Conversion) is carried out using the difference of water temperature between the cold DOW (5°C) and the warm surface water (25°C). Second, a fresh water generation by a desalination of the sea water is carried out using residual difference of temperature after OTEC operation. Third, the DOW after discharging cold temperature in the heat exchanger of fresh water generator is scattered into a photosynthetic surface layer in the sea and its nutrient enhances primary production of the sea and eventually make a rich fishing ground. Forth, Lithium and some other rare metal are absorbed from DOW by putting special filters in the continuous large quantity flow of DOW. In this paper, the multi-purpose DOW platform which generates the electric power, the fresh water, the fishes and the Lithium from only DOW and surface water is proposed as a supplier of infra-structure for an isolated island. Technical and economical feasibility study is carried out and the result is that the enough sized multi-purpose DOW platform is very feasible for the forthcoming environment era.


A blue-sensitive multiplier phototube was used to measure light scattered from a parallel beam in distilled, tap and sea water, the first named serving as a check upon errors from extraneous sources of light. Forward and back scatter are closely the same for distilled water, but with natural waters by far the greater part of the effect occurs through angles less than 25°. A minimum is found for a deviation of about 110°, back scattering increasing somewhat for greater angles. The relative importance of forward scatter increases with turbidity, and in sea water about three-quarters of the effect is due to matter removable by filtration through a collodion filter of average pore diameter 1 μ or by sedimentation; further passage through 0·6 and 0·2 μ filters produces little change. Scattering is greater in blue light. Plymouth tap water scatters more than surface coastal water and the latter more than surface water 20 miles out, station E 1. Surface water scatters more than deeper—the water column being remarkably homogeneous even when a well-marked thermocline had existed for weeks, but a small increase was detectable at the top of the cold water. E 1 surface water increased in scattering between August and January, and decreased till May. Deep water showed little change. Extinction due to scattering between 20 and 155° amounted to less than one-sixth of that found for a similar sample with a Pulfrich photometer, so probably much scattering occurs below 20°. This explains why Pulfrich extinctions are so much greater than vertical extinction coefficients found in the sea. The preponderance of forward scattering within the range 20 to 155° and the effects of filtration suggest that such scattering is due chiefly to refraction through transparent mineral particles, large compared with the wave-length of light. The refractive index of organic matter is too near that of water to produce refraction through angles as large as 20°. Such matter may, however, be responsible for some of the scattering through smaller angles which apparently accounts for most of the turbidity found with the Pulfrich photometer.


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