Experimental studies in the salinity tolerance of turtle grass Thalassia testudinum
Doering, P.H.; Chamberlain, R.H. (2000). Experimental studies in the salinity tolerance of turtle grass Thalassia testudinum, in: Bortone, S.A. (Ed.) Seagrasses: monitoring, ecology, physiology, and management. pp. 81-98
In: Bortone, S.A. (Ed.) (2000). Seagrasses: monitoring, ecology, physiology, and management. CRC Marine Science Series, 16. CRC Press: Boca Raton. ISBN 0-8493-2045-3. 318 pp., meer
In: Kennish, M.J.; Lutz, P.L. (Ed.) CRC Marine Science Series., meer
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| Auteurs | | Top |
- Doering, P.H.
- Chamberlain, R.H.
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| Abstract |
The effects of salinity on the growth and survival of turtle grass, Thalassia testudinum, were examined using laboratory mesocosms. Plants collected from the Caloosahatchee Estuary (southwest Florida} were exposed to five constant salinity treatments (6, 12, 18, 25, or 35‰) for 43 days. Two independent experiments were conducted: one during the winter dry season and the other during the summer wet season. Although there were differences between the two seasonal experiments, these differences were independent of salinity .T. testudinum survived exposure to a salinity of 6‰ for 6 weeks in both seasons. Af ter 6 weeks exposure, number of blades, number of blades/shoot, and biomass of blades were similar in the range 12-35‰, but all three parameters exhibited a relative decrease at 6‰. The final length of blades achieved at the end of the experiment increased steadily as salinity increased. In general, production and elongation of new blades were observed at all salinities. Elongation rates of newly formed blades were positively correlated with salinity. The net production of blades was positive at salinities of 12‰ or greater, but ceased at 6‰. The phosphorus and nitrogen content of blades and rhizomes was inversely related to salinity. The biomass of blades in the mesocosm experiments was within the range observed in the Caloosahatchee. Both in the field and in the laboratory, blade biomass increased as salinity increased. Our experimental results suggest that given unlimited light, parameters of growth in T. testudinum are negatively impacted at salinities between 6 and 12‰. |
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