Valor nutritivo das ervas marinhas na Baía de Bazaruto

Abstract

The study on the nutritional value of seagrasses in Bazaruto Bay was carried out in August 2007. Six seagrass species were collected, namely Halophila ovalis, Halodule uninervis, Thalassodendron ciliatum, Cymodocea rotundata, Thalassia hemprichii and Nanozostera capensis. Samples were randomly collected from various seagrass mats in Bazaruto Bay. Sampling consisted of collecting whole plants and about 500 g of fresh samples were taken for each species. In the second phase, the samples were transported to the laboratory, dehydrated, mo ied and analysed for the following parameters: organic matter, ash, total nitrogen, total starch, neutral detergent fibre and lignin, separated into two fractions, above substrate (ACS) and below substrate (ABS). All analyses were done in triplicate. Halodule uninervis was the species with the highest nitrogen content (1.5 ± 0.03%). Halophila ovalis was the species with highest ash content (39.3 ± 1.74%), highest dry matter content (88.8 ± 0.47%) and lowest organic matter content (60.7 ± 1.74%). Thalassodendron ciliatum had the lowest ash content (7.4 ± 1.74%), highest organic matter content (92.6 ± 1.74%), neutral detergent fibre (52.3 ± 1.03%) and lignin (17.4 ± 0.91%) relative to all other species collected from Bazaruto Bay Nanozostera capensis was the species with the lowest FDN content (31.7 ± 1.03%), and highest starch content (8.3 ± 0.16). Cymodocea rotundata was the species with the lowest dry matter content and intermediate for all other nutritional parameters. Most of the nutrients were concentrated higher above the substrate, except for organic matter where the concentration was higher below the substrate.(TRADUÇAO NOSSA)