Diversity index of species in sandbar present in estuarine ecosystem of Agusan River, Philippines: Its threat, management and conservation

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Research Paper 03/08/2023
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Diversity index of species in sandbar present in estuarine ecosystem of Agusan River, Philippines: Its threat, management and conservation

Marjorie Jane G. Badilla, Sarah Jane T. Pabatang, Diana Rose Norberte, Rissa L. Mercado, Minie L. Bulay, Julie S. Berame
Int. J. Biosci.23( 2), 47-59, August 2023.
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Estuary is a unique ecosystem due to the gradients of ecological conditions from riverine to marine. In some cases, there is sandbar in an estuary which rarely gets attention in scientific activities and conservation management. At the mouth of the Agusan River, the Philippines, where freshwater from the Agusan River and saltwater from Butuan Bay converge, lies one of Mindanao’s most significant estuaries with the presence of sandbar. The aim of this study is to identify all the available species (flora, fauna, and fungi) in the sandbar located in an estuary along the Agusan River and know the possible threats happening on the sandbar. The study used a descriptive method to examine many viewpoints and discover connections between the complex relationships among species on the sandbar. We utilized diversity parameters formulated as Shannon’s diversity, richness, evenness, and dominance indices. The results showed that the sandbar had Shannon’s diversity index of 1.231 featuring a low diversity level due to anthropogenic activities such as water pollution and habitat fragmentation that can negatively affect the species in the sandbar. Based on the International Union for Conservation of Nature, it appeared that species present in the sampling area were categorized under Vulnerable (VU), Near Threatened (NT), and Least Concern (LC). This meant that some of the species in the sampling area may be gone for approximately 10 years from now if not given proper attention and care. We strongly suggest strengthening the conservation and management plan like continuous mangrove planting and security provided by the Local Government Unit of the place. This study concluded that the place should undergo a more thorough evaluation to come up with better management and conservation planning.


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