Abundance, Distribution and Diversity of Seagrass Species in Lagoonal Reefs on the Kenyan Coast

Swaleh Ali Aboud, John Forkpa Kannah

Abstract


The study described the diversity of Seagrasses, measuring the canopy height and relative abundance in Diani, Nyali, Kanamai and Vipingo seagrass meadows along the Kenyan Coast. Using a 1 m2 quadrats along a predetermine line transect, the percentage cover and the species density of Seagrasses were measured respectively to compare the diversity of the observed species between the study sites. The canopy height associated was also documented at each study site. The data collected was subjected to Shannon - Weiner Diversity Index to determine the species density and ANOVA for variation. The index provides more information about community composition by taking into account the relative abundances and evenness of different species. Data was collected from December, 2013 to January, 2014. There was a significant difference in seagrass abundance and canopy height between the four study sites. Kanamai had higher abundance while Nyali recorded high species diversity (p<0.05). T. ciliatum recorded high canopy height and was connected to its higher productivity. It was concluded that Seagrasses species abundance and diversity showed spatial variation within and between the study sites and that levels of protection affect herbivore rates thus higher abundance in unprotected site. The work recommends further research should specifically target the source of changes in seagrass abundance and distribution between the study sites through time, and determine if any other stressors (nutrients, epiphytes, etc.) contributed to the loss of seagrass habitat in these sites.


Keywords


Density; Canopy height; Relative Abundance; Percentage cover; Productivity.

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References


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