Biomass measurements and weight-to-weight conversion factors: a comparison of methods applied to the musselMytilus galloprovincialis

✍ Scribed by P. Palmerini; C. N. Bianchi

• Book ID: 104734356
• Publisher: Springer-Verlag
• Year: 1994
• Tongue: English
• Weight: 491 KB
• Volume: 120
• Category: Article
• ISSN: 0025-3162
• DOI: 10.1007/bf00349688

✦ Synopsis

Wet weight to ash-free dry weight conversion factors were calculated for the bivalve Mytilus galloprovincialis Lamarck; specimens were collected in November 1989 in the Magra Estuary (eastern Ligurian Sea, Italy). Ash-free dry weight was determined by four different methods: (A) mechanical separation of shell and body; (B) shell dissolution with HC1; (C) dissolution of organic matter with NaC10; (D) incineration of the whole organism. The results obtained by these four methods were significantly different, indicating that caution is necessary when comparing biomass data obtained by different methods. Incineration and decalcification with HC1 seem to be the best procedures: they not only combine accuracy with speed, but are also the most universally applicable, being equally suitable for soft-bodied or hard-bodied organisms. Mechanical separation can lead to an underestimation of the biomass, whereas treatment with NaC10 can lead to its overestimation. However, no method can be considered the best in absolute terms, the final choice depending on the particular weight measurement required (e.g. shell-free dry weight) and the nature of the organism concerned (e.g. an organism with a large carbonate content).