A Community Based Mangrove Rehabilitation of High Energy Coasts in Pedada Bay, Philippines
Keita Furukawa, Jurgenne H. Primavera, Rona Joy A. Loma, Christian L. Montilijao, Jofel D. Coching, Yvainne Y. Sta. Maria, and Fernando P. Siringan
For coastal communities, fringe mangrove forests can help to protect their coasts from high energy waves and provide various ecosystem services. Nevertheless, these forests are under threat of damage caused by climate change and variability and stress related to development. Coastal hydrology / morphology is one of key processes to be monitored and assessed to implement an appropriate management especially for mangrove rehabilitation. This paper reports on the lessons learnt from the Community based mangrove rehabilitation of a fringed mangrove project in the Pedada bay, Philippine. The sea floor level in the area was too low (less than 0.5 m below the Mean Sea Level or MSL) and exposed to high energy waves from the sea. A pair of breakwaters was constructed for reducing the wave energy, but sea floor level could not be amended artificially in January 2010. Thus, the first plantation attempt failed. Nevertheless, continuous monitoring of sea floor level has been conducted and the ongoing sedimentation processes been traced. The maximum sedimentation rate was recorded at 0.5 m / year in the region during 2012-2013. The survival rates of Avicennia marina, Sonneratia alba, and Rhizophora mucronata were 44.0 %, 73.6 %, and 0 %, respectively (during 2010-2013), due to differences in natural succession and tolerance of species. In 2013, the area was battered by Typhoon Yolanda (Nov. 2013), but the breakwaters and sheltered mangroves survived. These attempts emphasize the importance of an integrated management with community participation and a science based approach.