Runoff of Suspended Soil and Nutrients from an Upland Watershed, Okinawa Island

• Nakandakari Tamotsu

  The United Graduate School of Agricultural Sciences, Kagoshima University

• Yoshinaga Anshun

  Faculty of Agriculture, University of the Ruckus

• Sakai Kazuhito

  Faculty of Agriculture, University of the Ruckus

• Akiyoshi Yasuhiro

  Faculty of Agriculture, Miyazaki University

• Osawa Kazutoshi

  Graduate School of Science and Technology, Tokyo Institute of Technology

Bibliographic Information

Other Title

• 沖縄本島の畑地帯流域における浮遊土砂と栄養塩の流出
• オキナワ ホントウ ノ ハタチタイ リュウイキ ニ オケル フユウ ドシャ ト エイヨウ エン ノ リュウシュツ

Abstract

Suspended soil and nutrients have caused sea water pollution in coral reef seas in Okinawa. The purpose of this study was to research on runoff of suspended soil and particulated nutrients from a small upland watershed in Okinawa island. For the purpose of this study, we observed the runoff at several rainfall events occured during 2006. At the outlet of the watershed, discharge and rainfall data were collected through the year. Water samples were collected at the outlet during each event. Concentrations of suspended soil, nitrogen and phosphorus were analyzed. From the observed results, the runoff concentrations of suspended soil and nutrients were higher than that during non-rainfall periods. Time series of concentrations of participated nitrogen and phosphorus showed the similar trend to that of suspended soil. The participated nutrients were the main component of the total nutrients flowed out of the watershed. High correlation coefficients between suspended soil load and nutrient load were estimated. In conclusion, the results indicate that runoff of suspended soil and particulated nutrients from an upland watershed are closely linked, and further suggest that the runoff management contributes to conservation of sea water quality environment.

Journal

• Journal of Rainwater Catchment Systems

  Journal of Rainwater Catchment Systems 13 (1), 37-43, 2007

  Japan Rainwater Catchment Systems Association

Keywords

• Suspended soil
• Particulated nutrients
• Reddish soil runoff management
• Sea water pollution in Okinawa

Details

• CRID: 1390282679462013312
• NII Article ID: 110006381572
• NII Book ID: AA11657953
• DOI: 10.7132/jrcsa.kj00004675585
• ISSN: 21866228
• ISSN: 13438646
• NDL BIB ID: 9404070
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I9404070
• Web Site: https://www.jstage.jst.go.jp/article/jrcsa/13/1/13_KJ00004675585/_pdf
• Text Lang: ja
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed