| Project/Area Number |
22580169
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Forest science
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| Research Institution | Forestry and Forest Products Research Institute |
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Principal Investigator |
SHINOMIYA Yoshiki 独立行政法人森林総合研究所, 立地環境研究領域, 主任研究員 (20353716)
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| Co-Investigator(Kenkyū-buntansha) |
OHDOSHI Kunio 高知大学, 農学部, 教授 (00127060)
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| Project Period (FY) |
2010 – 2012
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| Project Status |
Completed (Fiscal Year 2012)
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| Budget Amount *help |
¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000)
Fiscal Year 2012: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000)
Fiscal Year 2011: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000)
Fiscal Year 2010: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000)
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| Keywords | 森林 / 気候変動 / 豪雨 / 台風 / 栄養塩 / 窒素 / 微細土砂 / 平成24年豪雨 / TN / SS / 硝酸態窒素 |
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| Research Abstract |
We investigated nutrients runoff (Suspended solid material, SS; Total nitrogen, TN; Nitrate, NO3 -) from a forested, mountainous catchment in the Shimanto River headwaters, comparing among “event”(total rainfall below 200 mm), “storm event” (total rainfall 200 ～ 300 mm) and “extreme storm event“(total rainfall 742 mm in 18-19 July, 2011). The vegetation of the experimental catchment (73ha), underlying sedimentary rock, is a secondary forest of predominantly evergreen trees. Stream water was collected every two hours using an automatic water sampler for 6 flood events (total rainfall 53 ～ 742 mm). TN runoff during “extreme storm event” (about 5 kg ha-1 yr-1) is equaled to the averaged value of annual TN runoff (4.9 kg ha-1 yr-1) reported by previous studies. The proportion of NO3 --N to TN for specific cumulative output drastically decreased from 28 ～76 % in “event” and“storm event” to 2 % in “extreme storm event”. It revealed definitely that particulate matter runoff overwhelmingly more than dissolved matter for nitrogen during “extreme storm event”.
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