ID 110978
Title Alternative
THE MAIN CAUSE OF “SINKING EVENT” AT A COMPENSATIVE ARTIFICIAL TIDAL FLAT IN OKINOSU, TOKUSHIMA CITY
Author
Higashi, Kazuyuki
Ota, Naotomo
Hashimoto, Atsushi
Otani, Sosuke
Keywords
artificial tidal flat
bioturbation
Nihonotrypaea japonica
“sinking event”
field experiment
Content Type
Journal Article
Description
徳島市沖洲地区にある人工海浜は,埋め立てられる既存海浜の代償措置として造成されたが,既存海浜の底生生物相を再現できていなかった.決定的な違いはホソウミニナの有無であり,その原因は沖洲人工海浜で確認されている「沈み込み現象」によるものと推察された.筆者らは「沈み込み現象」の発生原因として,ニホンスナモグリに着目した.その結果「沈み込み現象」は,ニホンスナモグリの生息域のみで発生していること,加えてニホンスナモグリを排除すると「沈み込み現象」は発生しないことを示した.また,ニホンスナモグリはホソウミニナの生残に負の影響を与えることも分かった.しかしニホンスナモグリを排除することで,底生生物相が貧弱になる結果も示されており,ニホンスナモグリが干潟生態系へ与える影響は極めて複雑であることが示された.
Description Alternative
An artificial tidal flat was created in 2007, to compensate for the loss of a natural tidal flat, at Okinosu, Tokushima City. However, five years after its creation, it was found that the ecological conditions in the artificial habitat of benthic animals differed vastly from those in the natural habitat. In particular, the mud snail Batillaria cumingi, which dominates natural tidal flats, was rarely found in the artificial habitat.
 We tested the hypothesis that the “sinking event” was caused due to bioturbation by the ghost shrimp, Nihonotrypaea japonica. The “sinking event” occurred only at the places where N. japonica was abundant. Therefore, it seemed that bioturbation by N. japonica was the cause of the “sinking event”. Although exclusive treatment with N. japonica led to a low-biodiversity assemblage, N. japonica has both positive and negative effects on the tidal flat ecosystem.
Journal Title
土木学会論文集B3(海洋開発)
ISSN
21854688
Publisher
公益社団法人 土木学会
Volume
72
Issue
2
Start Page
I_718
End Page
I_723
Published Date
2016
Rights
© 2016 公益社団法人 土木学会
EDB ID
DOI (Published Version)
URL ( Publisher's Version )
FullText File
language
jpn
TextVersion
Publisher
departments
Research Center for Management of Disaster and Environment