Biomass and dynamics of Thalassia testudinum in the Mexican Caribbean: elucidating rhizome growth

Abstract

ABSTRACT. We report here data on biomass and dynamics of shoots and rhizomes of Thalassia testudinum in the Mexican Caribbean based, primarily, on aging of plant material. We found 7 testudinum to be able to reach high biomass (> 1000 g dry wt m-') and develop highly productive populations (1500 to 4500 g dry wt m-' annually, of which 10% were allocated to the rhizomes) in the Mexican Caribbean. The plants appeared to grow slowly, as reflected in longer time intervals in between production of leaves and shoots, and slower rhizome elongation rates and leaf production rates than found in the past, possibly as a result of their low nutrient, particularly phosphorus, content. Calculated maximum shoot life spans ranged between 6 and 9 yr, shoot recruitment rates ranged from 0.02 to 0.07 In units per plastochrone interval (PI) and shoot mortality rate was substantial and averaged about 0.045 In units PI-' Shoots turned over at ca 0.6 yr-', which also represents the rhizome turnover rate.

Growth patterns and demography of pioneer Caribbean seagrasses Halodule wrightii and Syringodium filiforme

“…On the basis of data obtained using plant dating techniques (Patriquin 1973, Gallegos et al 1993, Marba et al 1994, we describe the biomass, and rhizome and shoot dynamics of monospecific Syringodium filiforme and Halodule wrightii meadows in the Mexican Caribbean.…”

“…We studied shallow (1.0 to 1.5 m) monospecific meadows of Syringodium filrforme and Halodule wrightii on the reef lagoon near the town of Puerto Morelos (21" N, 87" W, Yucatan Peninsula, Mexico;Marba et al 1994), using the approach described by Gallegos et al (1993). In August 1991, the time of maximum seagrass biomass in the area (Van Tussenbroek 1994), we randomly collected 6 and 3 cores (20.5 cm internal diameter) from the S. filiforme and H. wrightii meadows, respectively.…”

Vertical growth and short-shoot demography of Syringodium filiforme in outer Florida Bay, USA

“…However, very few short-shoots appear to live beyond year 2 and the oldest shortshoot recorded, was approximately 3.5 yr old. Despite morphologi.cal and density differences, the age structure of the Florida Bay population is very similar to the Mexican population, corroborating that Syringodium filiforme has a shorter lifespan and higher shortshoot turnover rate than Thalassia testudinum (Gallegos et al 1993, 1994, Durako 1994.…”

“…The vertical stems of Cymodocea serrulata (R. Brown) normally grow above the sediment surface (Vermaat et al 1995), while a closely related species, Cymodocea nodosa (Ucria), maintains its vertical meristems at, or very near, the sediment surface . Thalassia testudinum (Banks ex Konig) also maintains its vertical meristem near the sediment surface, to the extent that sediment accretion leads to increased vertical stem growth (Gallegos et al 1993. Where vertical growth keeps up with sediment accumulation, T. testudinum traps sedlments and forms elevated mudbanks which modify local hydrography (Zieman 1982).…”

Habitat-dependent growth in a Caribbean sea urchin Tripneustes ventricosus: the importance of food type

“…Primary production on many coral reefs is dominated by diverse species of macroalgae, whereas seagrass beds are dominated by a few species of seagrass (Iverson and Bittaker 1986;Gallegos et al 1993;Dawes et al 1995;Aronson and Precht 2000;Lirman and Biber 2000;Kendall et al 2004). Seagrasses contain relatively high levels of indigestible, refractory compounds and high C/N ratios (Duarte 1990(Duarte , 1992Enriquez et al 1993;Anesio et al 2003;Montague et al 2005;Vichkovitten and Holmer 2005).…”