Storm runoff and sediment discharge during the typhoon 200514 (Nabi) were
monitored in three forested basins (WS1: 6.6 ha, WS2: 9.2 ha, WS3: 8.2 ha) at the
Sarukawa Experimental Watershed located in Mivazaki Prefecture, southwestern
Japan. Dormant geology in the area is chaotic beds of mudstone and sandstone within
the Shimanto Belt (an accretionary prism). The total amount of precipitation
associated with the typhoon storm event was 1,156 mm. Although the maximum 1-hr
precipitation was 40.5 mm/hr and not exceptionally higher than average annual
record, high and intense rainfall (precipitation >23 mm/hr) continued 19 hours.
During the storm event, the greatest peak and total catchment runoff was observed
in WS1 and WS3 and direct storm runoff coefficient became 83 and 98% respectively.
Sediment discharge volumes measured by deposits behind weir ponds of WS1, WS2
and WS3 were 2.5, 7.3 and 1.9 m3/ha, respectively. Several slope failures occurred
on hillslopes and zero-order hollows in WS2. Hence, the greatest sediment discharge
observed at the weir of WS2 potentially associated with remobilization of deposited
material within the channels and riparian zones, because most of sediment due to
slope failures deposited on the foot of hillslopes. Continuous monitoring of runoff and
sediment discharge will help to understand the spatial and temporal variations of
sediment supplied, deposit and transport in forested watersheds.
雑誌名
地形
巻
28
号
2
ページ
127 - 142
発行年
2007-04-25
ISSN
03891755
書誌レコードID
AN00333248
権利
日本地形学連合
フォーマット
application/pdf
形態
2688588 bytes
著者版フラグ
publisher
日本十進分類法
451.5
その他の言語のタイトル
Runoff and Sediment Discharge Triggered by the Typhoon 200514 (Nabi) in Forested Watersheds, Southern Kyushu, Japan
九州南部の森林流域における2005年台風14号豪雨による出水と土砂流出
chikei28_2_127-142.pdf
(2.69MB)
