Typhoon-induced changes in mangrove and its impact on livelihood resources in Palawan, Philippines | |
| Author | Montoya, Pia Collado |
| Call Number | AIT Thesis no.NR-23-01 |
| Subject(s) | Mangrove forests--Philippines Typhoons--Philippines Natural resources--Environmental aspects--Philippines |
| Note | A thesis submitted in patial fulfillment of the requirements for the degree of Master of Science in Natural Resources Management |
| Publisher | Asian Institute of Technology |
| Abstract | Global climate change fuels more disastrous typhoons threatening mangroves and coastal communities' welfare. There is a 10% mangrove loss yearly due to typhoons, but few studies on the impact of the typhoon on mangroves in Southeast Asia have been done. By 2100, mangrove loss is projected in Asia, including the Philippines, a country also located in the typhoon belt region. This study aims to assess the status of the mangrove after Typhoon Rai and the livelihood impact in Palawan, Philippines. Normalized Difference Vegetation Index was performed using sentinel-2 datasets collected between pre-typhoon (2021) and post-typhoon (2022), representing the vegetation condition before and after the typhoon. A household survey interview was conducted in 266 mangrove-dependent households. Key informant interviews with 12 selected respondents, two focus group discussions, and a field visit were done to validate the results of changes in mangroves and their impact on livelihood. The result shows that between pre-typhoon (2021) and post-typhoon (2022), the dense, sparse, and bare mangrove vegetation relative change to about -96.05% (-15091.1 hectares), 1649.46% (13605.14 hectares), and 191.92% (1485.83 hectares), respectively. The sudden decline of dense mangroves resulted in the above-ground biomass and carbon stocks between pre- and post-typhoon. It is estimated that above ground carbon stocks were reduced by 71.62% (-1274296.45 MgC) between 2022 and 2021. The mangrove changes caused disturbances in ecosystem productivity and impacted livelihood resources. The households had experienced the highest yield decline of shrimp, crab, mangrove clam/bivalve, mangrove snails, sea cucumber, nipa, and ecotourism operations. The derived income from mangrove resources dropped to about 50.27%, equivalent to an income loss of Php 77, 858.59 (1405.57 USD) between pre typhoon (2021). There is no mangrove management or program designed explicitly for typhoon aftermath. Hence, most households recognize that there are mangrove interventions implemented in the community that are typhoon relevant. However, household participation is low. Mangrove intervention, especially in the bare mangrove sites, is necessary to increase the recovery rate and reverse mangrove and livelihood losses. Providing livelihood assistance to the household lacking livelihood strategies helped to sustain their household income while flow of mangrove ecosystem services is still recovering. |
| Year | 2023 |
| Type | Thesis |
| School | School of Environment, Resources, and Development |
| Department | Department of Development and Sustainability (DDS) |
| Academic Program/FoS | Natural Resources Management (NRM) |
| Chairperson(s) | Shrestha, Rajendra Prasad |
| Examination Committee(s) | Sasaki, Nophea;Kavinda Gunasekara |
| Scholarship Donor(s) | Asian Development Bank Japan Scholarship Program (ADB-JSP) |
| Degree | Thesis (M. Sc.) - Asian Institute of Technology, 2023 |