Recovery from the impact of light reduction on the seagrass Amphibolis griffithii, insights for dredging management

MARINE POLLUTION BULLETIN

卷:62

Article

McMahon, Kathryn^1,2  Lavery, Paul S.^1,2  Mulligan, Michael³ 

[1] Edith Cowan Univ, Ctr Marine Ecosyst Res, Joondalup, WA 6027, Australia

[2] Edith Cowan Univ, Sch Nat Sci, Joondalup, WA 6027, Australia

[3] Mulligan Environm, Geraldton, WA 6530, Australia

关键词: Dredging;    Light reduction;    Recovery;    Seagrass;    Amphibolis griffithii;    Australia;   

DOI  :  10.1016/j.marpolbul.2010.11.001

来源: Elsevier

【 摘 要 】

A large-scale, manipulative experiment was conducted to examine the extent and rate of recovery of meadows of the temperate Australian seagrass, Amphibolis griffithii to different light-reduction scenarios typical of dredging operations, and to identify potential indicators of recovery from light reduction stress. Shade cloth was used to mimic different intensities, durations and start times of light reduction, and then was removed to assess the recovery. The meadow could recover from 3 months of light stress (5-18% ambient) following 10 months re-exposure to ambient light, even when up to 72% of leaf biomass was lost, much faster recovery rates than has previously been observed for large seagrasses. However, when the meadow had been shaded for 6-9 months and more than 82% of leaf biomass was lost, no recovery was detected up to 23 months after the light stress had ceased, consistent with other studies. Five potential indicators of recovery were recommended. (C) 2010 Elsevier Ltd. All rights reserved.

【 授权许可】

Free