Pacific waters

S], [DA], [DP], represent respectively the concentrations of the given element in warm surface water, deep Atlantic water, and deep Pacific water. 

Fig. 15-9 Depth profiles for NOT, POt, and Cd observed at station 64 off the coast of California in April 1977. (Reprinted with permission from Bruland, K. W. et al. (1978). Cadmium in Northeast Pacific waters, Limnol. Oceanogr. 23, 618-625, Society for Limnology and Oceanography.)...

Kharkar DP, Thomson J, Turekian KK, Forster WO (1976) Uranium and thorium series nuclides in plankton from the Caribbean. Limnol Oceanogr 21 294-299 Krishnaswami S, Lai D, Somayajulu BLK, Weiss R, Craig H (1976) Large-volume in situ filtration of deep Pacific waters mineralogical and radioisotope studies. Earth Planet Sci Lett 32 420-429 Livingston HD, Cochran JK (1987) Determination of transuranic and thorium isotopes in ocean water in solution and in filterable particles. J Radioanal Nucl Chem 115 299-308 Masque P, Sanchez-Cabeza JA, Braach JM, Palacios E, Canals M (2002) Balance and residence times of °Pb and 4 o in surface waters of the northwestern Mediterranean Sea. Cont Shelf Res 22 2127-2146 Matsumoto E (1975) Th-234-U-238 radioactive disequilibrium in the surface layer of the oceans. Geochim Cosmochim Acta 39 205-212... 

Krishnaswami S, Lai D, Somayajulu BLK (1976) Large-volume in-situ filtration of deep Pacific waters Mineralogical and radioisotope studies. Earth Planet Sci Lett 32 420-429 Krishnaswami S, Mangini A, Thomas JH, Sharma P, Cochran JK, Turekian KK, Parker PD (1982) °Be and Th isotopes in manganese nodules and adjacent sediments nodule growth histories and nuclide behavior. Earth Planet Sci Lett 59 217-234... 

Pacific waters near Australia. These jellyfish have been known to cause death within hours or even minutes of a stingT Along the beaches of Australia, warning signs are often posted to remind swimmers to beware of the box jellyfish. 

The situation is more complex in the region of Asia and the Pacific. Water quality has many enemies there. First, sedimentation constitutes a major cause of pollution in Asian rivers, since sediment loads are four times the world average. Secondly, hazardous and toxic waste deteriorates the water quality. It is noteworthy that lead levels in Asia s surface water are about 20 times higher than those in OECD countries. Thirdly, eutrophication is faced due to the extensive use of fertilizers in the last 30 years. But the list of problems does not end here. Asian rivers contain three times as many bacteria from human waste as the world average. Finally, urbanization and the release of untreated sewage and industrial waste to the environment are expected to cause severe water pollution problems. 

Lee, D.S. (1983) Palladium and nickel in northeast Pacific waters. Nature, 305, 47M8. 

Livingston, H.D., Bowen, VT., Caso, S.A., Volchok, H.L., Noshkin, VE., Wong, K.M. and Beasley, T.M. (1983) Fallout Nuclides in Atlantic and Pacific Water Columns. GEOSECS Data, Technical Report WHOI-85-19, Woods Hole Oceanographic Institution, Woods Hole, MA. 

Piepgras, D.J. and Jacobsen, B. (1992) The behavior of rare earth elements in seawater precise determination of variations in the North Pacific water column. Geochim. Cosmochim. Acta, 56, 1851-1862. 

Tsunogai S. and Watanabe Y. (1981) Calcium in the North Pacific water and the effect of organic matter on the calcium-alkalinity relation. Geochem. Jour. 15, 95-107. 

Phaeocystis sp. (Prymnesiophyceae). II. Pigment Composition. J Phycol 34 496-503 Wells ML (1999), Manipulating iron availability in nearshore waters. Limnol Oceanogr 44 1002-1008 Wells ML, Price NM, Bruland KW (1994) Iron limitation and the cyanobacterium Synechococcus in equatorial Pacific waters. Limnol Oceanogr 39 1481-1486 Worthen DL, Arrigo KR (2003) A coupled ocean-ecosystem model of the Ross Sea. Part 1 Interannual variability of primary production and phytoplankton community structure. In DiTullio GR, Dunbar RB (eds) Biogeochemistry of the Ross Sea. Antarct Res Ser 78 93-105... 

In solving Equation 9, we have taken the pH of deep Pacific water to be 7.8, the amount of particulate matter to be 15 yg 1 (P. G. Brewer, unpublished data, 1978) and the residence time of particulate matter to be 3.65 years (consistent with the mean sett ling velocity of 2 x 10" cm sec given by Krishnaswami (12)... 

Krishnaswami, S., Lai, D., Somayajulu, B.L.K., Weiss, R. F., and Craig, H. Large-volume situ filtration of deep Pacific waters mineralogical and radioisotope studies. 

Early studies looked at both dissolved free and combined amino acids (DFAA and DCAA, respectively) in total DOM, where HMWDOM proteins are a subset of the DCAA fraction. Lee and Bada (1975) first reported DFAA concentrations in the range of 40—50 nM in surface Pacific waters and total hydrolysable amino acid (THAA = DFAA + DCAA) concentrations that were often 10 times higher. To date, the observed range of TFIAA is approximately 250—650 nM in surface waters (Dittmar et al., 2001, 2004 Hubberten et al., 1995 Yamashita and Tanoue, 2003). Lee and Bada (1975) observed an approximate three-fold decrease in THAA below the euphotic zone (at these depths DFAA became negligible). This trend was also seen in more recent studies where amino acid concentrations decreased to between 160 and 360 nM in mid-depth waters (Hubberten et al., 1995 Yamashita and Tanoue, 2003). McCarthy et al. (1996) found that HMWDOM-DCAA concentrations were 178 and 278 nM in surface waters of the Sargasso Sea and North Pacific Ocean, respectively. 

The nitrate flux from the Arctic to the Atlantic was estimated by Galloway et al. (1996) as 1500 x 10 mol year, with most of the nitrate due to Pacific water... 

Nagata, T., Fukuda, H., Fukuda, R., and Koike, I. (2000). Bacterioplankton distribution and production in deep Pacific waters Large-scale geographic variations and possible couphng with sinking particle fluxes. Limnol. Oceanogr. 45, 426—435. 

Bruland K. W., Knauer G., and Martin J. (1978a) Cadmium in Northeast Pacific waters. Limnol. Oceanogr. 23, 618-625. 

Martin J. H., Knauer G. A., and Gordon R. M. (1983) Silver distributions and fluxes in the North-east Pacific waters. Nature 305, 306 - 309. 

Dissolved and particulate concentrations of Fe have been shown to be quite low in the euphotic zone of the North Pacific oligotrophic and eastern equatorial Pacific waters. The dissolved concentration is normally lower than 0.1 nM and the particulate is about 0.2 nM. The concentration along the water column shows a nutrient-type vertical profile characterized by surface depletion and increase with depth. Iron concentration reaches typically values >0.5 nMat depths below 1000 m (158). 

The California Current flows southward along the western coast, moving cold, North Pacific water toward the equator. 

During the 1980s, it was believed that trace metal concentrations, especially toxic metals such as Cd, Pb, and Hg, in Baltic Seawater should be much higher in relation to Atlantic or Pacific waters because they were directly controlled by riverine (fluvial), atmospheric and sediment-related inputs, and by their biogeochemical behavior. Table 13.1 demonstrates that Baltic offshore waters nowadays show comparatively lower trace metal concentrations than what was expected about 30 years ago. 

The distribution of a number of dissolved species (02, C-14, Ra-226, salinity) in the Central Pacific water column, at depths between 1 and 4 km, has been shown (11) to be consistent with a steady-state model of the water column in which the concentration-depth profiles are stationary and the concentrations at the boundaries 1 and 4 km are stipulated at their present values. The physical model of the water column is based on two transport mechanisms vertical eddy diffusion (eddy diffusion coefficient K — 1.3 cm2 sec"1) and upwelling of deep water (advection velocity U = 1.4 X 10 5 cm sec"1, or approximately 1 cm per day) (11). 

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