Advertisement

Prevention of River-Mouth Closure Using a Jetty and Recovery of Spawning Ground of Horseshoe Crab

  • T. UdaEmail author
  • R. Konishi
  • S. Tashiro
  • Y. Ashikaga
  • Y. Ooki
Conference paper

Abstract

At the mouth of the Maite River flowing into Nakatsu tidal flat which faces the Suonada Sea, a river-mouth jetty using gravel net was extended to block longshore sand transport from the nearby coast into the river mouth. The effect of the jetty appeared within two months after the installation of the jetty, and sand deposition inside the river mouth was mitigated. Sand was deposited immediately west of the jetty, and it was found that such a sand mound was used for horseshoe crab Tachypleus tridentatus as a spawning ground. The recovery of sandy beach west of the jetty was effective for the protection of sand dune as a natural levee.

Keywords

Nakatsu tidal flat Maite River river-mouth improvement gravel net horseshoe crab spawning ground 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Seino, S., Uda, T., Tsuchiya, Y., Maeda, K. and San-nami, T. (2000). Field observation of geomorphological features of the spawning site and dispersion of hatchings of the horseshoe crab Tachypleus tridentatus - towards mitigation planning for the rare species-, Ecol. Civil Eng. Vol. 3 (1), pp. 1-19. (in Japanese)Google Scholar
  2. Seino, S., Ashikaga, Y., Uda, T., Mihara, H., Watanabe, S. and Oki, Y. (2011). Monitoring of sand dune and vegetation zone after setback of coastal defense line on Nakatsu tidal flat in Oita Prefecture, Proc. of Hydraulics, JSCE, Vol. 55, pp. 1687-1692. (in Japanese)Google Scholar
  3. Sakai, K., Uda, T., Seino, S. and Ashikaga, Y. (2011). Sand circulation offshore of mouth of a river flowing into tidal mud flats, Coastal Sediments’11, pp. 2311-2324.Google Scholar
  4. Uda, T. (1997). Beach erosion in Japan, Sankaido Press, Tokyo, p. 442. (in Japanese)Google Scholar

Copyright information

© Springer Nature Singapore Pte Ltd. 2020

Authors and Affiliations

  • T. Uda
    • 1
    Email author
  • R. Konishi
    • 2
  • S. Tashiro
    • 2
  • Y. Ashikaga
    • 3
  • Y. Ooki
    • 1
  1. 1.Public Works Research CenterTokyoJapan
  2. 2.Nakatsu Public Works Office, Oita Prefectural GovernmentNakatsu CityJapan
  3. 3.Nakatsu Waterfront Conservation AssociationNakatsuJapan

Personalised recommendations