| Project/Area Number |
02454057
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
土壌・肥料
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| Research Institution | HOKKAIDO UNIVERSITY |
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Principal Investigator |
SAKUMA Toshio FACULTY OF AGRIC.,HOKKAIDO UNIV. PROFESSOR, 農学部, 教授 (50001756)
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| Co-Investigator(Kenkyū-buntansha) |
TANAKA Yumiko EXPERIMENT FOREST, FACULTY OF AGRIC., HOKKAIDO UNIV. INSTRUCTOR, 農学部・附属演習林, 技官教務職員 (60221397)
SATOH Fuyuki EXPERIMENT FOREST,FACULTY OF AGRIC., HOKKAIDO UNIV. ASSIS. PROFESSOR, 農学部・附属演習林, 助手 (20187230)
HATANO Ryusuke FACULTY OF AGRIC.,HOKKAIDO UNIV. ASSOC. PROFESSOR, 農学部, 助教授 (40156344)
FUJIWARA Koichiro EXPERIMENT FOREST, FACULTY OF AGRIC., HOKKAIDO UNIV. PROFESSOR, 農学部・附属演習林, 教授 (00001503)
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| Project Period (FY) |
1990 – 1992
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| Project Status |
Completed (Fiscal Year 1992)
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| Budget Amount *help |
¥6,000,000 (Direct Cost: ¥6,000,000)
Fiscal Year 1992: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1991: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1990: ¥5,200,000 (Direct Cost: ¥5,200,000)
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| Keywords | Acid rain / Forest degradation / Forest soils / pH-buffering / Geo-chemical cycle / dry deposition / Forest hydrology / Channel water quality / 森林土譲 / pH緩衝作用 / 土壌生成作用 / 酸性土壌 |
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| Research Abstract |
Observations on the material cycling in some forest ecosystems were conducted and the influences of acidic deposition on the processes were discussed. The composition and pH of acidic deposition were strongly modified by accumulation, intake, base release, and excretion of organic compounds from forest canopy. Under deciduous forests, throughfall pHs were significantly higher than rainfall pHs, but those under coniferous forests were generally lower than rainfall pHs. Apparently, conifers were more effective as the collector of air pollutants. The efficiency of Pinus strobus were more than three times of mixed deciduous forests. The O horizon of forest floor showed strong pH-buffering, especially under deciduous forests. It acid neutralizing capacity was estimated as large as 20 - 30 times of present H^+ load in the area under consideration. On the other hand, the pHs of soil solution were largely controlled by soil processes, such as nitrification and base exchange phenemena. The cycling of sulfer and nitrogen in the forest ecosystems was not, so far, affected by atmospheric inputs, but self-controlled by characteristic biochemical processes of the forest ecosystems. The discharge and water quality of stream channels were also affected by biological processes in forest stand and surface soil horizons. In addition, the flux of dry deposition onto snow surface was considerable, 30-100mumolc m^<-2> day^<-2> for major ions. The influence of acidic air-pollutants was enhanced by accumulation and transport in snow-pack during winter time.
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