Survival, Morphology and Reproduction of Enhalus Acoroides (L.F.) Royle in the Bolinao-Anda Reef System, NW Philippines: Effects of Varying Light Conditions
Date: 2023-06-28
Degree: Doctoral Thesis
Programme: Doctor of Science
Authors: Karen Arano Tagulao
Supervisors: Prof. Rene Rollon, University of the Philippines (Supervisor), Prof. Chan Shek Kiu, University of Saint Joseph (Co-supervisor)
Abstract:
Seagrasses play a critical role in coastal ecosystems worldwide, providing various ecosystem services based on their region and genus. In Southeast Asia, where seagrass biodiversity and coverage are at their highest, the livelihoods and food security of many coastal communities depend on these plants. Despite their ecological and economic importance, seagrasses face global threats from human activities such as pollution and land use changes.
Enhalus acoroides, a widely distributed seagrass species in the tropical Indo-Pacific region, is particularly valuable for coastal management and conservation efforts due to its size and provision of various ecosystem services. Although previous research has indicated that it is less sensitive to environmental changes than other tropical seagrass species, recent reports highlight its vulnerability to siltation and eutrophication.
This dissertation aimed to examine how Enhalus responds and adapts to changes in light availability, taking into account both morphological adaptation and phenotypic plasticity. Field surveys, reciprocal transplantation field experiments, and investigations of sexual reproductive effort were conducted in the Bolinao-Anda Reef system to evaluate the impact of long-term environmental changes on Enhalus populations.
The findings of this study reveal that Enhalus has the capacity to adapt its traits and survive changes in depth, light gradients, and different habitat types. Reciprocal transplantation experiments indicate a high survival rate, indicating the potential for rehabilitation. This thesis underscores the need for further research on Enhalus’ response to stressors, genetic variation, and adaptive capacity to address conservation and management challenges.
