Links About Seagrass:

http://www.springerlink.com/content/kr902353u7637x1w/

http://en.wikipedia.org/wiki/Seagrass 

http://www.canada.com/vancouversun/news/story.html?id=2fb35467-064e-4335-a26d-779c71486178&k=87947

A lovely book about Seagrass:
http://books.google.ca/books?id=dHV0NA3m2AIC&dq=how+were+Japan%27s+seagrass+levels+affected&q=Japan#v=snippet&q=Japan&f=false