THE INFLUENCE OF NUTRIENTS ON THE DISTRIBUTION OF SEAGRASS IN THE MALINDI MARINE PARK AND RESERVE
KOMBE, CLARICE AMANI
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This study examined the influence of nutrients on seagrass. Seagrass are marine angiosperms that serve a critical role in the conservation of marine species and promotion of coastal livelihoods. Seagrass continue to record huge declines around the world due in part, to nutrient enrichment associated with expanding coastal cities, increase of agricultural activities and climate change. Spatial and temporal variations of nutrients (nitrites, nitrates, phosphates and ammonium) in water and sediments of Malindi were studied from October 2015 to May 2016. Samples were collected from three stations; inside the Marine Park, Buffer zone and Reserve and were analysed colometrically for nutrients. The results from this study showed that seagrass attained a higher mean percentage cover in the reserve (90%) as compared to the park (60%) and the buffer zone (70%). Nutrient levels significantly varied in sediments than in water. The concentration of nutrients in sediments for site 1, 2 and 3 ranged from 0.055-82.214 mg/l, 0.083-36.38mg/l, 0.05-35.012, and 0.26-25.824mg/l for phosphates, ammonia, nitrates and nitrites respectively, while the concentration in water for site 1, 2 and 3 ranged from; 0.002 - 0.176mg/l, 0.001 - 1.554mg/l, 0.002 - 0.167mg/l and 0.001-0.158 mg/l for phosphates, ammonia, nitrates and nitrites respectively. Overall higher levels of nutrients were found in site 1 as compared to site 2 and site 3. Silt was a major component in sediments followed by sand then clay. Correlation analysis indicates that ammonia, nitrates and nitrites play a role in influencing seagrass biomass; the other nutrients did not show any significance. This study recommends continuous monitoring of data on the concentration levels of nutrients in water and sediment of seagrass-based protected areas in relation to the distribution of seagrass. This will help in strengthening the design and presence of seagrass-based protected areas and their efficacy in managing land-based pollution.