| Project/Area Number |
17380111
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
General fisheries
|
|---|
| Research Institution | Tohoku University |
|---|
Principal Investigator |
TANIGUCHI Kazuya Tohoku University, Tohoku University, Graduate School of Agricultural Science, Professor (40282082)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SATO Minoru Tohoku University, Graduate School of Agricultural Science, Professor (70050680)
AGATSUMA Yukio Tohoku University, Graduate School of Agricultural Science, Associate Professor (50292256)
ITO Kinuko Tohoku University, Graduate School of Agricultural Science, Assistant Professor (90191931)
|
|---|
| Project Period (FY) |
2005 – 2007
|
| Project Status |
Completed (Fiscal Year 2007)
|
| Budget Amount *help |
¥15,960,000 (Direct Cost: ¥15,300,000、Indirect Cost: ¥660,000)
Fiscal Year 2007: ¥2,860,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥660,000)
Fiscal Year 2006: ¥3,300,000 (Direct Cost: ¥3,300,000)
Fiscal Year 2005: ¥9,800,000 (Direct Cost: ¥9,800,000)
|
|---|
| Keywords | allelochemical / marine algae / herbivore''s larva / sessile diatom / isoyake / bromophenol / inhibition of metamorphosis / tribromomethane / ジブロモフェノール / トリブロモフェノール / 増殖阻害 / ヒバマタ目褐藻 / 海中林 / カジメ / 光合成 / 栄養塩濃度 / クロロフィル量 / キタムラサキウニ / エゾバフンウニ / 変態 / 無節サンゴモ |
|---|
| Research Abstract |
In addition to food web, marine organisms in rocky coastal ecosystem are connected through allelochemicals produced from marine algae. In the present study, a new experimental system demonstrated the hypothesis that marine algae eliminate herbivore's larvae and sessile diatoms. Die-off of macrophyte constituting marine forest during summer autumn and subsequent inhibition of the growth, and the mortality lead to the marine deforestation, "Isoyake". We clarified for the first time that the main factor leading to "Isoyake" is low nutrient level instead of high water temperature. An original experimental system using dibromomethane, a chemical inducer of the larval settlement and metamorphosis showed that the bromophenols produced and released from the brown algae Eisenia bicyclis and Ecklonia kurome inhibit larval metamorphosis of sea urchin and abalone and kill these larvae in the presence of 1 ppm and 10 ppm, respectively. Low concentrations of 1-5 ppm bromophenols also inhibit proliferation of sessile diatoms on the thallus surface. Former studies on the allelochemicals of marine algae have targeted to Laminariales algae. From GC-MS analysis of cultured seawater of 11 Fucales species and Analipus japonicus, we obtained novel results that the five Fucales species and A. japonicus release bromophenols and 10 Fucales species release tribromomethane, which is produced from crustose coralline red algae and more toxic too herbivore's larvae.
These results contribute to elucidate the mechanism of alternative stability of rocky coastal ecosystem, and establish systematization of the ecosystem management with sustainable high productivity.
|
