Publication Date:
2014-08-23
Description:
The effects of temperature and salinity on the metabolism of the Asiatic clam Corbicula fluminea (mollusca, Lamellibranchia) were studied experimentally. Firstly, three indexes of basal metabolism (oxygen consumption rate, OCR; ammonia excretion rate, AER; and CO2 emission rate, CER), patterns of diurnal rhythm and O: N ratios were measured for three size ranges (large: h = 25.54 +/- 1.96 mm, medium: h = 22.07 +/- 1.33 mm and small: h = 17.70 +/- 1.43 mm) at two salinities (0.3[per mille sign] and 1.8[per mille sign]). The results showed that: (1) three indexes decreased with increasing body size. (2) no significant difference was found between two salinities for the O: N ratios of the small and large size, but a significant difference was found for the medium-sized one; (3) however, there were similar and distinct diurnal rhythms of metabolic rate at two salinities over a 24 hour period in three size C. fluminea.OCR, AER, CER, O: N ratios and Q10 (temperature coefficient) of small-sized C. fluminea were measured across five water temperatures (4, 11, 18, 25 and 32[degree sign]C) and two salinities (0.3[per mille sign] and 1.8[per mille sign]) in the following experiments. Our results of the small C. fluminea were as follows: there was no significant difference in the O: N ratios among the five temperatures and two salinity treatments; and no significant difference of three indexes between both salinity levels were observed at same temperature controlled; and three indexes increased significantly with increasing temperature from 4[degree sign]C to 25[degree sign]C, while no significant difference was observed in the 25-32[degree sign]C range; and the highest Q10 coefficients (Q10 = 1.825 at salinity of 0.3[per mille sign] and Q10 = 1.683 at salinity of 1.8[per mille sign]) were observed at the 18-25[degree sign]C temperature increase, and the low values were found in the 4-11[degree sign]C, 11-18[degree sign]C and 25-32[degree sign]C interval. It indicates that there is not a synergetic effect of our temperature and salinity on the metabolic rate of small C. fluminea, and a temperature of 18-25[degree sign]C may represent an optimum adequate metabolic temperature range. For the purposes of ecological monitoring and restoration, small individuals of C. fluminea planted are more likely to survive than larger ones.
Electronic ISSN:
2193-1801
Topics:
Natural Sciences in General
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