Use of stable isotopes in the studies on cycling of water and ions in ecosystem.
Project/Area Number |
60860008
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Research Category |
Grant-in-Aid for Developmental Scientific Research
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Allocation Type | Single-year Grants |
Research Field |
土壌・肥料
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Research Institution | Hokkaido University |
Principal Investigator |
SAKUMA Toshio Faculty of Agriculture, Hokkaido University , Associate Prof., 農学部, 助教授 (50001756)
|
Co-Investigator(Kenkyū-buntansha) |
HATANO Ryusuke Faculty of Agriculture, Hokkaido University , Instructor, 農学部, 助手 (40156344)
森下 諦三 東京農業大学, 講師
OKAJIMA Hideo Faculty of Agriculture, Hokkaido University , Prof., 農学部, 教授 (60001385)
MORISHITA Taizo The Tokyo University of Agriculture , Leeturer
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Project Period (FY) |
1985 – 1986
|
Project Status |
Completed (Fiscal Year 1986)
|
Budget Amount *help |
¥10,700,000 (Direct Cost: ¥10,700,000)
Fiscal Year 1986: ¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 1985: ¥9,000,000 (Direct Cost: ¥9,000,000)
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Keywords | stable isotopes / deuterium water / <^(15)N> / TCD-gaschromatography / tension lysimeter / intake rate / 物質循環 / 安定同位元素 / トレーサー / 土中水分移動 / 土中イオン移動 / TCD-ガスクロマトグラフィー / 疎水性触媒ビーズ |
Research Abstract |
To solve the problems concerning to the tracer use of deuterium water(HDO) in soils, following studies were conducted : 1) Accuracy of the determination of HDO concentration in purified water samples by using a TCD-gaschromatography, 2) methods to separate and purify the water samples for the analysis, 3)natural abundance of HDO and its fluctuation in marine and terrestrial waters, including soil water. 1) The standard error of the determination of HDO concentration by the TCD-gaschromatography was less than +2 ppm when the low HD carrier gas obtained by electrolysis of light water(HDO conc.=11 ppm) was used. 2) A tension lysimeter method was developed to collect the samples of soil solution for the DHO determination in the field. The isotope effect during the extraction was slight when soil water suction was less than 250cmH20. It is concluded that the extraction by the tension lysimeter method is hardly applicable when soil water suction is higher than 300cmH20. 3) Natural abundance of HDO in soils was in the range from 135 to 150 ppm. Some field experiments were conducted to obtain additional information on the application of HDO as a tracer of water under the field condition. During the determination of infiltration capacity by using the double ring infiltrometer, extremely uneven distribution of infiltrated water was noticed. It was concluded that the scale of cylinder was not sufficiently large in comparison with the scale of macropore systems in soils. In field experiments the added HDO was diluted rapidly and was hardly traceable, especially when the soil wetness was high, as in the case of peat soils.
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Report
(2 results)
Research Products
(8 results)