Seagrass meadows on tropical Indo-Pacific reef islands: How do water motion and water depth relate to seagrass species composition, and are seagrass communities really controlled by shrimp bioturbation?


Contact
Dominik.Kneer [ at ] awi.de

Abstract

The present study investigated the distribution pattern of six tropical seagrass species on two coral islands in the Spermonde Archipelago, Indonesia. Shoot density, leaf area index, biomass and rhizome length of Halophila ovalis, Halodule uninervis, Syringodium isoetifolium, Cymodocea rotundata, Thalassia hemprichii and Enhalus acoroides were related to water motion and water depth. At research sites with high water motion the seagrass sucession was frequently disrupted by blowouts and moving sandbars, and small seagrass species were dominant. In areas with moderate water motion bare sand patches produced by alpheid shrimp became more prominent, and all six seagrass species were sometimes found forming mixed stands. In sheltered areas mounds and funnels produced by callianassid shrimp were abundant and only the two species T. hemprichii and E. acoroides were present. Assemblages in intertidal areas were dominated by T. hemprichii and C. rotundata. The highest densities of callianassid shrimps were found in deep, sheltered, seagrass-free areas. Shrimp were excluded from experimental plots in one such area and all six seagrass species were transplanted into exclusion, procedural control and zero treatment plots. At the end of a two-year monitoring period, T. hemprichii and S isoetifolium had disappeared from all plots; however C. rotundata, H. uninervis and H. ovalis had successfully established themselves on some of the exclusion plots. There was a marked seasonality, with decreasing water quality during the Northeast monsoon seasons being followed by a decline in shoot numbers inside the plots. Also, seagrass shoots numbers where higher in plots located in shallower water.



Item Type
Conference (Poster)
Authors
Divisions
Programs
Peer revision
Not peer-reviewed
Publication Status
Published
Event Details
International Seagrass Biology Workshop, 25 Nov 2012 - 30 Nov 2012, Buzios, Rio de Janeiro, Brazil.
Eprint ID
31818
Cite as
Kneer, D. , Priosambodo, D. and Asmus, H. (2012): Seagrass meadows on tropical Indo-Pacific reef islands: How do water motion and water depth relate to seagrass species composition, and are seagrass communities really controlled by shrimp bioturbation? , International Seagrass Biology Workshop, Buzios, Rio de Janeiro, Brazil, 25 November 2012 - 30 November 2012 .


Download
[img]
Preview
PDF
Kneer_et_al_ISBW_2012.pdf

Download (2MB) | Preview
Cite this document as:

Share

Research Platforms
N/A

Campaigns


Actions
Edit Item Edit Item