| Project/Area Number |
12575032
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 海外学術 |
|---|
| Research Field |
Environmental dynamic analysis
|
|---|
| Research Institution | The University of Tokyo |
|---|
Principal Investigator |
KOIKE Isao The University of Tokyo, The University of Tokyo, Ocean Research Institute, Professor (30107453)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
MKAI Hiroshi Hokkaido Univ., NFC., Professor (00013590)
MOJIMA Satoshi 九州大学, Faculty of Science, Associate Prof. (30112288)
IIZUMI Hitoshi 水産総合研究センター, Fisheries Research Agency Japan Sea National Fisheries Research Institute, Section head(Researcher) (00159550)
KOGURE Kazuhiro Univ.of Tokyo, ORI., Professor (10161895)
NAKAOKA Masahiro Chiba Univ., Faculty of Science, Associate Prof. (90260520)
相生 啓子 東京大学, 海洋研究所, 助手 (90107459)
|
|---|
| Project Period (FY) |
2000 – 2002
|
| Project Status |
Completed (Fiscal Year 2002)
|
| Budget Amount *help |
¥14,600,000 (Direct Cost: ¥14,600,000)
Fiscal Year 2002: ¥4,100,000 (Direct Cost: ¥4,100,000)
Fiscal Year 2001: ¥5,000,000 (Direct Cost: ¥5,000,000)
Fiscal Year 2000: ¥5,500,000 (Direct Cost: ¥5,500,000)
|
|---|
| Keywords | tropical seagrass beds / sediment re-suspension / stable isotope / -Halophila beds / species diversity / benthic population / southern Thailand / coastal conservation / 陸起源物質 / 沿岸生態系 / 沿岸堆積物 / ^<15>N同位体 / 有機懸濁物 / 干出ストレス / 移植実験 / 光光合成曲線 / マングローブ / 潮汐流 / 窒素循環 / 熱帯藻場 / 集水域 / 人間活動 / 堆積物 / 水質 |
|---|
| Research Abstract |
Field studies were conducted under the title "Conservation of tropical seagrass beds with special reference to their role on function of coastal ecosystem" to quantify the stress of terrestrial nutrients, sediment materials and human changes of coastal line on seagrass ecosystem including benthic populations facing to the Andaman Sea side of Thailand. Followings are major research outcomes of this project.
1) We analyzed how the dominated species of seagrass adapts to external environmental change such as sediment supply and decrease of light intensity. And we indicated the importance of morphological adaptation of seagrasses including the fine roots of vertical rhizomes, as well as adjustment of photosynthetic products distribution among upper and below bottom.
2) Stable isotope ratios of nitrogen, carbon and sulfur within the various parts of seagrasses could be used as a good indicator of small scale environmental stress. on seagrass metabolisms
3) Comparison of species diversity and biomass distributing different environmental setting, from the location of big river mouth to that of no river inflow influence, indicated that both biomass and species diversity of seagrass decreased with the increase of river influences at least in this study area.
4) Based on the field observations of physical forcing causing re-suspension of seagrass sediments, we identified three factors, i.e., tidal current, wind induced re-suspension and inflow or terrestrial solids. Even within the rather narrow area of seagrass beds, spatial and temporal variation of these three factors were observed, also effecting on metabolisms of benthic organisms associated with seagrass beds,
5) Food preference of dugong for different types of seagrass species was examined and importance of Halophila beds for the diet of dugong of this area.
|
