In order to understand the actual effect of endocrine disrupting chemicals on aquatic animals inhabiting the Tama and the Kitakami Rivers as well as the potential health and ecological effects of such chemicals on river wildlife species, the gonado-somatic index (GSI), gonado morphology, plasma vitellogenin (VTG) and thyroxine (T₄) levels, and hepatic microsomal Cytochrome P-450 (Cyt. P-450) content of carp, Cyprinus carpio, caught at lower parts of the rivers were studied in May and November, 1998. No abnormality was observde in the ovaries of female carp from both rivers or in the testes of male fish from the Kitakami River in May. There was no significant difference in plasma VTG levels from female carp collected at the Tama and those collected at the Kitakami in May and November. On the other hand, some male fish from the Tama River displayed testicular abnormalities (about25%) and higher levels of plasma VTG (approximately50%) than those from the Kitakami River in May. Significant negative relationship between GSI and plasma VTG levels was also indicated in male fish from the Tama River at that time. Furthermore, in November high plasma VTG was found in male carp from the Tama River.
No significant difference in plasma T₄ and hepatic Cyt. P-450 content from carp collected at both rive was recorded. A positive relationship between hapatic Cyt. P-450 content and plasma VTG level was found in male carp from the Tama River in May. In November, a significant negative relationship between hepatic Cyt. P-450 content and plasma T₄ level was detected in female carp from the Kitakami River and in male fish from both rivers. A significant relationship between plasma T₄ and VTG levels was not indicated in female or male carp from either river.
On the basis of these findings,(i) it is concluded that the reproductive health and maybe other physiological functions of male carp inhabiting the Tama River which runs through the Tokyo metropolitan area are perhaps being influenced by exposure to oestrogenic substances, while the effects on female carp are not clear, and (ii) it suggested that female and male carp inhabiting the Kitakami River are also incurring endocrine dysfunctions by means of chemical contaminants, though the extent is not so severe as that in the Tama River.

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Manganese oxide adsorbents containing pentavalent metal (V, Nb, Sb, or Bi) were prepared by acid treatment of pentavalent metal-doped lithium manganese oxide with spinel structure. Their lithium adsorptive properties in sea water were studied batchwise. The addition of Nb, V, or Bi caused an increase in the lithium adsorptive capacity by 25-30%. The Nb-containing adsorbent seems to be the most promising adsorbent among the pentavalent metal-doped manganese oxides due to its high chemical stability and large adsorptive capacity for lithium in sea water. The increases in the lithium uptake by doping Nb could be explained by the increase in the number and the acidity of adsorption sites selective to lithium ions.

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The afforestation of arid areas is expected to make an appreciable contribution to global carbon sequestration. The final target of this project is increasing carbon stock by 5-20 times the present level by afforestation using methods such as efficient water harvesting, irrigation, soil-improvement cultivation, careful species selection and a large increase in rainfall. Near Leonora in Western Australia, where the mean annual rainfall is 220mm/y, factors for successful afforestation are water, soil, salt and nutrition for carbon sequestration; to be specific, saturated hydraulic conductivity, depth of soil, salt concentration and nutrition concentration. The results of measurements at eight sites in the area have been reported for saturated hydraulic conductivity rang-ing from 5.0×10^-4 to 2.8×10^-3cm/s, with the depth of soil ranging from 30 to 180cm, salt concentrations ranging from 0.05 to 0.40meq/100g, nutrition concentrations ranging from 0.11 to 0.36meq/100g, and fixed carbon quantity assessment ranging from 0 to 49t-C/ha. Based on these measurement results, a flow chart is proposed for determining the controlling factors and those that should be improved. This paper mainly describes the relation between salt and biomass from the view point of salt concentrations in soil and leaf. Growth of E. camaldulensis needs a saturated hydraulic conductivity of 1.9×10^-3 cm/s, a depth of soil of 180cm, a salt concentration of 0.05meq/ 100g and nutrition concentration of 0.36 meq/100g. The growth of Acacia. aneura needs a saturated hydraulic conductivity of 2.8×10^-3cm/s, a depth of soil of 60cm, a salt concentration of 0.09meq/100g and a nutrition concentration of 0.36meq/100g. Results of Na/K ratio in leaves of Melaleuca sheathiana indicate that it tolerates.

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Bacterial abundances were extensively measured using both the AO direct count method and the DAPI direct count method in the productive layer (upper 200m) of the North Pacific Ocean and the Bering Sea in order to determine the quantitative significance of bacterial biomass as a carbon pool in the euphotic zone. The bacterial abundances measured with the AO method, with a range of 1.5-33×10⁵ml^-1,revealed higher values in the upper 50 mand gradually decreased at depths below 50 min all regions. The bacterial abundances measured with the DAPI method, with a range of 1.0-23×10⁵ml^-1, were lower than those measured with the AO method, at all stations and depths. The difference between the DAPI method and the AO method in bacterial abundance varied in term of both region and depth. This difference meant that the abundance of non-bacterial organic particles varied with the region and with the depth, while real bacterial abundance also varied with the region and with the depth. The bacterial carbon biomass accounted for 2-18%(average;8±4%) of the total particulate organic carbon pool (which including bacterial carbon). This result suggested that the quantitative significance of bacterial carbon biomass might be comparable with that of the phytoplankton carbon biomass in the productive layer of the North Pacific Ocean.

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Dissolved DNA (D-DNA) and Dissolved RNA (D-RNA) in seawater were measured in the productive layer (200m in depth) over a wide area of the North Pacific Ocean (from the central subarctic region to the central tropical region) including the Gulf of Alaska and the Bering Sea. The concentrations of D-DNA and D-RNA ranged from 0.5μg l^-1 to 16μg l^-1 and from 1.8μg l^-1 to 25μg l^-1 at all the stations, respectively. The ratio of RNA/DNA was within a range of 1-15 at all the stations. The concentrations of both D-DNA and D-RNA were higher in the upper water column (50m in depth) and lower in the lower water column (100-200m in depth) in respective regions. The concentration of D-DNA in the upper water column showed some regional variation; higher in the Bering Sea, and lower in the Gulf of Alaska and in the central tropical region. In contrast, the concentration of D-DNA in the lower water column did not show any regional variations. On the other hand, the concentration of D-RNA in the upper water column also showed some regional variations; higher in the Bering Sea and lower in the Gulf of Alaska. The spatial variation of D-DNA concentrations may be directly influenced by the biomass of bacteria. In contrast, the D-RNA concentrations may be directly influenced by the biological activity of bacteria in situ rather than by the biomass of bacteria.

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The concentrations of dissolved deoxyribonucleic acid (D-DNA) and dissolved ribonucleic acid (D-RNA) were measured using both Whatman GF/F filters and 0.2μm Nuclepore filters in the subarctic coastal seawater of Funka Bay, for the purpose of studying the biogeochemical significance of D-DNA and D-RNA in seawater., The concentration of D-DNA in terms of total dissolved portion (filtered out with the GF/F filters) proved to have a temporal variation (1.2-6.0μgl^-1 average; 3.1 ± 1.5 μg l^-1) in the water column between spring and summer. The concentration of D-RNA in terms of the total dissolved portion also proved to have a relatively wide temporal variation (5.8-31.5μg l^-1, average; 13.8± 5.5 μgl^-1) in the water column. The D-DNA concentration and the D-RNA concentration in <0.2μm portion were estimated to be 60-100%(average; 83± 13%) of D-DNA in total dissolved portion and 46-100%(average; 78± 14%) of D-RNA in total dissolved portion, respectively. These results suggested that most D-DNA in total dissolved portion of seawater may be comprised of virus-DNA or free-DNA which have a poor variation temporally or vertically, whereas most D-RNA in total dissolved portion of seawater may be directly influenced by the biological activity of both viruses and bacteria as well as the existence of free-RNA.

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Concentrations of dissolved organic nitrogen and dissolved inorganic nitrogen in the porewater of marine sediment (0-30cm core length) werem easured in various marine environments (Bays, semipelagic sea, pelagic sea). The concentration of total dissolved nitrogen showed regional variations from 40μM in subtropical sediments to 1.3mM, two orders-of-magnitudhe higher, in Tokyo Bay sediments. The ammonium nitrogen concentration also showed regional variations over relatively wider range (three orders-of-magnitude), from 2μM in subarctic pelagic sediments to 1.2mM in Tokyo Bay sedimentsa nd 3-93% of the total dissolved nitrogen. The concentration of dissolved organic nitrogen, however, showed regional variations of relatively narrow range, from 10μM to 180μM and 3-87% of the total dissolved nitrogen. On the other hand, the concentration of nitrate (+nitrite) nitrogen showed regional variations of relatively low values, from 0.3μM in Otsuchi Bay to 49μM in the pelagic sediment and 0.2-70% of the total dissolved nitrogen.
The remarkable regional differences in concentrations and the proportion of respective nitrogen compounds might depend on the outcome in regional differences of diagenesis (ammonification, nitrification and denitrification) in marine sediment. The ammonium nitrogen and dissolved organic nitrogen in the porewater might be an important source for those in overlying seawater in the coastal environment, whereas these nitrogen compounds might not be so important as a source for those in overlying seawater in pelagic environments.

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The adsorption of uranium on a banded fiber adsorbent containing amidoxime groups (Banded-AOF) with a constant diameter (d=5 or 10mmφ) and a constant length (l=5-200mm) was examined by arranging Banded-AOF with a sinker attached to its deep end (σ=W/S=0.001 or 0.01kg/mm², where W is the weight of the sinker and S is the section area of Banded-AOF), in a stream of sea water with a velocity of 27cm/s. The adsorption rate of Banded-AOF increased with an increase in the ratio l/d, and reached a maximum value in the range of l/d>10; furthermore, it increased as the load σ decreased. This adsorptive toward uranium is explained by the shape of Banded-AOF in the stream of sea water: the middle region of Banded-AOF expanded more with an increase in l/d and a decrease in σ. The adsorption rate of Banded-AOF with l/d=20 and σ=0.001 kg/mm² in the sea water stream of 27cm/s was almost equal to that in a column experiment, exhibiting an uptake of uranium of 0.45mg/g for 14 days. The above results were consistent with those of the adsorption of uranium on Banded-AOF in tow in a natural sea area.

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Regularly-arrayed fines appeared in abraded part on the surface of a sodium chloride crystal growing in a flow cell. Liquid inclusions were formed by trapping mother liquor between the developed fines.

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