|Lepidochronology and internodal length methods for studying Posidonia oceanica growth: are they compatible?|
Peirano, A. (2002). Lepidochronology and internodal length methods for studying Posidonia oceanica growth: are they compatible? Aquat. Bot. 74(2): 175-180
In: Aquatic Botany. Elsevier Science: Tokyo; Oxford; New York; London; Amsterdam. ISSN 0304-3770, more
Age determination; Dating techniques; Growth; Rhizomes; Sea grass; Posidonia oceanica (Linnaeus) Delile, 1813 [WoRMS]; MED, Ligurian Sea [Marine Regions]; Marine
Two techniques to estimate growth of the Mediterranean seagrass Posidonia oceanica are compared. Leaf scale thickness and internodal length of orthotropic rhizomes were measured on the same rhizomes. Yearly cycles from internodal length measurements were in phase with lepidochronological years only after 3 years of rhizome growth. The start of a lepidochronological year roughly corresponded to the yearly maximum of internodal length measurements. Lepidochronology was a more sensitive method for identifying seasonal and yearly cycles. Both methods proved accurate and in agreement when samples exceeded 20 units (rhizomes). A combination of the two methods may improve dating techniques but the limitations should be taken into account when applied to population analysis and to primary production computations.