Experimental investigation into the effects of suspended sediment on fertilisation, larval survival and settlement in a scleractinian coral |
| |
Authors: | J Gilmour |
| |
Institution: | (1) Department of Zoology, University of Western Australia, Nedlands, Western Australia 6907, Australia Fax: 0061 (0)8 9380-1029 e-mail: jgilmour@cyllene.uwa.edu.au, AU |
| |
Abstract: | Laboratory and field experiments were used to determine whether high (≃100 mg l−1), low (≃50 mg l−1) and control (≃0 mg l−1) levels of suspended sediment affected fertilisation, larval survival, and larval settlement in the scleractinian coral Acropora digitifera (Dana, 1846). Both high- and low-sediment treatments significantly decreased fertilisation, but post-fertilisation embryonic
development was not inhibited by suspended sediments. Larval survival and larval settlement were significantly reduced in
high- and low-sediment treatments. No difference was found between high- and low-sediment treatments in any of the three post-spawning
processes investigated, suggesting that they are susceptible to sediment concentrations which are not exceptionally high even
under natural conditions (>50 mg l−1). The introduction of an additional stress in the form of high levels of suspended sediments coupled with naturally high
variability in recruitment may have a considerable effect on the successful supply and settlement of coral larvae to a reef.
Given that many coral communities are open reproductive systems, the consequences of disturbance events are not likely to
be restricted to the impact area. Recruitment to a population may be reduced significantly in the presence of high levels
of suspended sediments because of effects on larval survival and settlement. Recruitment of larvae to adjacent populations
may also be affected due to a decreased fertilisation success and potential increases in mortality of larvae passing through
the affected site.
Received: 13 August 1998 / Accepted: 22 July 1999 |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|