Intra and inter annual variation in a seagrass meadow on the Caribbean coast of Costa Rica: 2009-2015

Abstract

Seagrass beds are an important ecosystem on the Caribbean coast of Costa Rica. At Cahuita National Park (CNP) a seagrass bed at Perezoso has been monitored continually since 1999 within the CARICOMP program. Thalassia testudinum is the dominant seagrass species, in some cases mixed with Syringodium filiforme. The results from the 2009 to 2015 monitoring period are presented here, and contrasted with data before 2009. Total (above and below ground tissue) mean biomass of T. testudinum was higher (1 255.4 ± 146.0 gm-2) than biomass before 2009, with an increasing tendency. However, productivity (1.5±0.59 gm-2d-1) and turnover rate (4.3 ± 1.22 %d-1) were lower than previous monitoring periods. In this period, mean leaf area diminished considerably (4.9 ± 2.30 m2), but leaf area index (LAI) increased (1.9 ± 0.80 m2leafm-2) in comparison to prior monitoring. Productivity, density, turnover rate, LAI and biomass showed intra-annual variations; while mean biomass of T. testudinum did not vary significantly among years. No correlations were found between water salinity, temperature and clarity with seagrass measurements. However, most seagrass parameters were strongly correlated with precipitation. These results highlight the effect of external environmental agents acting on the ecosystem. CNP presents a long-term stable seagrass meadow. However, there are indirect signals, such as high biomass and above-ground biomass proportion, along with low productivity and LAI, which point to a nutrient increment in Perezoso’s seagrass bed. To continue protecting this seagrass bed, it is necessary to improve monitoring methods, and seagrass beds should be included in national conservation policies and monitoring programs.

Synchronized sexual reproduction of the seagrass Syringodium filiforme (Cymodoceaceae) in a tropical reef lagoon on the Caribbean coast of Costa Rica

“…In the Caribbean coast of Costa Rica there are six seagrass species and the most extensive meadows are found in Cahuita and Manzanillo (Samper-Villarreal et al 2018 (Fonseca et al 2007;Cortés et al 2010;Loría-Naranjo et al 2018). At the time of this study, Syringodium filiforme grew in these meadows in dense mono-specific patches (Fig.…”

“…There was no variability in S. filiforme shoot length between the months surveyed, in contrast with the seasonality found in other parts of the Caribbean. Seasonal variation in leaf dynamics (Barber & Behrens, 1985;Fry & Virnstein, 1988;Short et al 1993) andbiomass (Van Tussenbroek, 1994) (Loría-Naranjo et al 2018), with biomass and productivity reported to decrease at higher temperatures (Cortés et al 2010). The reasons for a lack of variation in S. filiforme shoot length during our study remain unclear, and potential confounding factors such as grazing dynamics (Valentine & Duffy, 2006) should be assessed at this study site.…”

“…Se delimita las Áreas Protegidas del Sistema Nacional de Áreas de Conservación (SINAC), resaltando el Parque Nacional Cahuita crest, and Thalassia testudinum is the dominant seagrass species. Seagrasses have been monitored regularly in Cahuita since 1999 as part of the Caribbean Coastal Marine Productivity (CARICOMP) Caribbean-wide monitoring program(Fonseca et al 2007;Cortés et al 2010;Loría-Naranjo et al 2018). At the time of this study, Syringodium filiforme grew in these meadows in dense mono-specific patches (Fig.3), which grew closer to the beach or in recent sites of disturbance…”

Las praderas de pastos marinos en Costa Rica

“…Dicho monitoreo se ha llevado a cabo utilizando la metodología del Programa de Productividad Costera y Marina del Caribe (CARICOMP), el cual hace mediciones de densidad, área foliar, productividad y biomasa de los pastos marinos en el Parque Nacional Cahuita. Los datos de dicho monitoreo se han analizado estadísticamente y los resultados se han publicado en múltiples artículos científicos (Fonseca, Nielsen & Cortés, 2007;Cortés et al, 2010;Loría-Naranjo et al, 2018).…”

Integrated Coastal and Marine Management in Costa Rica

“…En el Caribe Sur ha aumentado la presión sobre los hábitats de los arrecifes de coral debido al aumento de la sedimentación, principalmente vinculado a las prácticas agrícolas extensivas de banano y piña para exportación (Cortés y Risk, 1985;Cortés et al, 2010a). Las praderas de pastos marinos han presentado períodos de estabilidad y cambios a lo largo de los años (Cortés, 2010a;Van Tussenbroek et al, 2014;Loría-Naranjo et al, 2018). Los ecosistemas de manglar en el Caribe de costa Rica representan únicamente el 1% del total del país, y están concen-trados casi exclusivamente en el manglar de Gandoca en el Caribe Sur.…”