| Project/Area Number |
14580548
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Environmental dynamic analysis
|
|---|
| Research Institution | Toyohashi University of Technology (2004)
Gifu University (2002-2003) |
|---|
Principal Investigator |
INOUE Takanobu Toyohashi University of Technology, Professor, 工学部, 教授 (00184755)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
MATSUI Yoshihiko Gifu University, Professor, 工学部, 教授 (00173790)
MATSUSHITA Taku Gifu University, Research associate, 工学部, 助手 (30283401)
|
|---|
| Project Period (FY) |
2002 – 2004
|
| Project Status |
Completed (Fiscal Year 2004)
|
| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2004: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 2003: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 2002: ¥1,800,000 (Direct Cost: ¥1,800,000)
|
|---|
| Keywords | particulate phosphorus / bioavailable phosphorus / river / runoff loading / 藻類増殖 / 栄養塩 / 富栄養化 / 降雨時流出 / 面源負荷 |
|---|
| Research Abstract |
The sequence extraction method and algal growth potential examinations were applied to suspended solids in river water and watershed soil of the Nagara River watershed and the Asutani River watershed. Particulate Phosphorus were separated and defined as 9 forms by the sequence extraction method. Only particulate phosphorus in suspended solids from the river water or the soil of the watersheds used in the algal growth potential examinations.
The results of this study are the following :
1)During storm events, the inorganic phosphorus compounds soluble in bases, organic phosphorus, and redox-sensitive phosphorus bound to Fe and Mn were dominated among the particulate phosphorus forms of the river water, and the content of these phosphorus forms in particulate phosphorus ranged from 75% to 90%. The ratio of bioavailable phosphorus to particulate phosphorus was between 30% and 40%.
2)About 50% of total phosphorus in forest surface soil was organic, and about 40% in the paddy field surface soil was redox-sensitive phosphorus bound to Fe and Mn.
3)The algal growth potential examination indicated that the particulate form of phosphorus could be available for algal growth.
4)The algal growth potential examinations showed that the ratio of bioavailable phosphorus to total in forest surface soil and in paddy field surface soil were about 60% and 90%, respectively.
5)The ratio of bioavailable phosphorus to particulate solids calculated by the sequence extraction method was higher than that by the algal growth potential examination.
These results suggested that sequence extraction method is useful for the quantitative determination of bioavailable phosphorus in particulates. Further studies are necessary to know the reason of the difference between extracted sequence extraction method and bioavailability by algal growth potential examination.
|
