2000 Fiscal Year Final Research Report Summary
Water and mineral cycle in seasonal ground freezing basin
| Project/Area Number |
11691163
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| Research Category |
Grant-in-Aid for Scientific Research (B).
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| Allocation Type | Single-year Grants |
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| Section | 海外学術 |
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| Research Field |
林学
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| Research Institution | HOKKAIDO UNIVERSITY |
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Principal Investigator |
SASA Kaichiro Hokkaido Univ., University Forests, Prof., 農学部・附属演習林, 教授 (70125318)
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| Co-Investigator(Kenkyū-buntansha) |
NOMURA Mutumi Hokkaido Univ., University Forests, Lec., 農学部・附属演習林, 助手 (20271629)
UEMURA Shigeru Hokkaido Univ., University Forests, Asso.Prof., 農学部・附属演習林, 助教授 (80250497)
SATOH Fuyuki Hokkaido Univ., University Forests, Asso.Prof., 農学部・附属演習林, 助教授 (20187230)
SHIBATA Hideaki Hokkaido Univ., University Forests, Lec., 農学部・附属演習林, 助手 (70281798)
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| Project Period (FY) |
1999 – 2000
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| Keywords | Sakhalin / Northern Hokkaido / Seasonal ground freezing / Sasa community / Water cycle / Mineral cycle / Change of environment / 環境変化 |
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| Research Abstract |
Vegetation, snow depth, ground freezing, discharge of water and mineral cycle were investigated at the basin in which the ground freezes and one in which the ground does not freeze in Sakhalin and northern Hokkaido.
The existence of three species of sasa (Sasa krilensis, Sasa senanensis and Sasa nipponica) in Sakhalin was confirmed. Sasa krilensis and Sasa senanensis communities can survive in mid-winter environment only in area with a thick snow cover. And distribution of sasa communities provided mid-winter environmental indices in a cold and windy region. Most of snow cover in Sakhalin was depth hoar or solid-type depth hoar. And it became clear that forests in cold and windy region has function as snow accumulation and prevention of ground freezing. The depth of snow cover in area with no ground freezing exceeded 100m, indicating that at least 100cm of snow cover was needed to prevent ground freezing in Sakhalin, twice the depth needed to prevent ground freezing in Soya hills in northern Hokkaido. Daily mean amounts of water discharge in early January in the basin in which the ground freezes and one in which the ground does not freeze were 0.08mm/day and 0.13mm/day, respectably. These values, even though they were mean value for early mid-winter, were much smaller than the daily mean amount of water discharge recorded in Soya hills.
The results of this study suggest that, if global worming would advanced, forests in Sakhalin play a greater contributory role than do forest in nor thern Hokkaido in snow accumulation, prevention of ground freezing and discharge of water in mountain stream in winter.
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