Rhizome elongation and seagrass clonal growth

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 174:269-280 (1998) - doi:10.3354/meps174269 Rhizome elongation and seagrass clonal growth Núria Marbà1,*, Carlos M. Duarte2 1Centre for Estuarine and Coastal Ecology, NIOO, Korringaweg 7, 4401 NT Yerseke, The Netherlands 2Centre d'Estudis Avançats de Blanes, CSIC, Camí de Sta. Bàrbara s/n, E-17300 Blanes, Spain *Present address: Centre d'Estudis Avançats de Blanes, CSIC, Camí de Sta. Bàrbara s/n, E-17300 Blanes, Spain. E-mail: marba@ceab.csic.es ABSTRACT: A compilation of published and original data on rhizome morphometry, horizontal and vertical elongation rates and branching patterns for 27 seagrass species developing in 192 seagrass stands allowed an examination of the variability of seagrass rhizome and clonal growth programmes across and within species. Seagrass horizontal rhizomes extend at rates ranging between 1.2 and 574 cm yr-1, develop a branch, with an angle from 19 to 72°, for every 6 to 1800 horizontal internodes, and add a new shoot for every 1.1 to 7.5 cm of rhizome produced. Vertical rhizomes elongate at rates between 0.1 and 34 cm yr-1 and the probability that they will branch varies over 3 orders of magnitude. Much (between 40 and 173%) of the variability of seagrass horizontal rhizome and clonal growth programmes is species-specific, largely (21 to 63% of the variance) associated with differences in size among species, although seagrasses also show important intraspecific variability. The broad repertoire of seagrass rhizome and clonal growth programmes explains the different rates and efficiency at which the species occupy space. The implications of specific growth programmes for space occupation were examined by simulating the development of seagrass rhizome networks of 3 seagrass species encompassing the range of horizontal rhizome growth (Halophila ovalis, Thalassodendron ciliatum, Posidonia oceanica). This exercice showed that small, fast-growing species achieve a much lower spread efficiency (m2 of ground covered m-1 of rhizome produced) than the large, slow-growing species. Differences in rhizome branching angles greatly constrained the form of rhizome networks. The results show that clonal growth patterns are a primary component of seagrass productivity and, therefore, the key to the development and maintenance of seagrass meadows. KEY WORDS: Seagrasses · Clonal growth · Plant allometry · Rhizome diameter · Spacer length · Rhizome elongation · Branching rate and angle Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 174. Publication date: November 26, 1998 Print ISSN:0171-8630; Online ISSN:1616-1599 Copyright © 1998 Inter-Research.