Herbicide effects on the growth and photosynthetic efficiency of Cassiopea maremetens

Rowen, David J., Templeman, Michelle A., and Kingsford, Michael J. (2017) Herbicide effects on the growth and photosynthetic efficiency of Cassiopea maremetens. Chemosphere, 182. pp. 143-148.

[img]
Preview
PDF (Accepted Version) - Accepted Version
Download (5MB) | Preview
[img] PDF (Published Version) - Published Version
Restricted to Repository staff only

View at Publisher Website: https://doi.org/10.1016/j.chemosphere.20...
 
3
4


Abstract

Herbicides from agricultural run-off have been measured in coastal systems of the Great Barrier Reef over many years. Non-target herbicide exposure, especially photosystem II herbicides has the potential to affect seagrasses and other marine species. The symbiotic benthic jellyfish Cassiopea maremetens is present in tropical/sub-tropical estuarine and marine environments. Jellyfish were exposed to agricultural formulations of diuron or hexazinone to determine their sensitivity and potential for recovery to pulsed herbicide exposure. Jellyfish growth, symbiont photosynthetic activity and zooxanthellae density were analysed for herbicide-induced changes for 7 days followed by a 7 day recovery period. Both the jellyfish and endosymbiont were more sensitive to diuron than hexazinone. The 7-day EC50 for jellyfish growth was 0.35 µg.L-1 for Diuron and 17.5 µg.L-1 for Hexazinone respectively. Diuron exposure caused a significant decrease in(p<0.05) in jellyfish growth at all concentrations and at levels0.1 µg.L-1, a level that is below the regional Great Barrier Reef guideline valuesvalue. Jellyfish recovery was rapid with growth rates similar to control animals following removal from herbicide exposure. Both diuron and hexazinone caused significant decreases in photosynthetic efficiency (effective quantum yield) in all treatment concentrations (0.1 µg.L-1 and above) and this effect continued in the post-exposure period. As this species is frequently found in near-shore environments, they may be particularly vulnerable to herbicide run-off.

Item ID: 49843
Item Type: Article (Research - C1)
ISSN: 1879-1298
Keywords: jellyfish, inhibition, Great Barrier Reef, diuron, hexazinone, zooxanthellae
Funders: College of Marine and Environmental Sciences, James Cook University (JCU)
Date Deposited: 14 Aug 2017 05:10
FoR Codes: 05 ENVIRONMENTAL SCIENCES > 0502 Environmental Science and Management > 050206 Environmental Monitoring @ 50%
06 BIOLOGICAL SCIENCES > 0602 Ecology > 060205 Marine and Estuarine Ecology (incl Marine Ichthyology) @ 50%
SEO Codes: 96 ENVIRONMENT > 9611 Physical and Chemical Conditions of Water > 961104 Physical and Chemical Conditions of Water in Marine Environments @ 50%
96 ENVIRONMENT > 9605 Ecosystem Assessment and Management > 960503 Ecosystem Assessment and Management of Coastal and Estuarine Environments @ 50%
Downloads: Total: 4
Last 12 Months: 2
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page