Dolomite bad for Manila Bay; plant mangroves instead – UP scientists


Scientists from the University of the Philippines (UP) are pushing for the planting of mangroves in the shorelines of Manila Bay rather than overlaying is with crushed dolomite “white sand” to help solve environmental issues in the area.

The UP Institute of Biology reiterated that it is “strongly against” the overlaying of crushed dolomite on a portion of the Manila Bay shoreline, a rehabilitation and beautification project currently being carried out by the Department of Environment and Natural Resources (DENR).

“The dumping of dolomite sand on a reclaimed part of Manila Bay is not the best way of spending government money. The fund should have been directed to more viable, scientifically sound projects that can restore Manila Bay to a state that is fit for recreation,” it said.

The Institute also expressed its willingness to assist the DENR in implementing a science-based rehabilitation program for the heavily polluted bay that targets the recovery of its biological functions and services and understands the interplay between natural processes and human activities.

According to the group, environmental problems hounding Manila Bay caused by increasing human settlement and years of use and poor management moved the Supreme Court to issue a mandamus directing government agencies to clean, rehabilitate, and preserve the bay. This began in January, 2019 with three phases – cleanup/water quality improvement; rehabilitation and resettlement; and education and sustainment. 

However, the recent project involving the use of dolomite sand does not address any of these rehabilitation phases, adding that it is “even more detrimental to the existing biodiversity as well as the communities in the area,” it added.

Among those who will be affected by this project are migratory and resident birds, including species classified as “threatened” that use the whole stretch of the bay as a feeding, resting, roosting, and breeding area. 

“The dumping of dolomite in Manila Bay has effectively covered part of the intertidal area used by the birds thereby reducing their habitat,” the Institute explained.

For the rehabilitation program to be successful, the Institute recommended that the project should demonstrate a grasp of land-sea connectivity as well as possible immediate, short-term, and long-term impacts at species, ecosystem, and seascape scales. 

“Its core must be the strategic protection and conservation of biodiversity and ecological integrity providing the ecosystem services: the very reason why we need to rehabilitate Manila Bay,” it said.

Instead of dumping dolomite sand, the Institute pointed out that rehabilitating mangroves is a nature-based solution that is cheaper and more cost-effective.

It is also promoted by the International Union for Conservation of Nature (IUCN) as one of the most effective nature-based solution programs that can contribute in biodiversity conservation and climate change adaptation strategy. 

The group cited as example the mangroves in Las Piñas-Parañaque Critical Habitat Ecotourism Area (LPPCHEA), a protected wetland that is also managed by DENR, which has contributed in biodiversity conservation not just for shorebirds but also for various terrestrial and aquatic fauna. 

“Having ecologically healthy mangroves will also help lessen heavy metal contamination a condition that beset Manila Bay for a long time. A similar ecosystem- and/or bay-wide approach can be implemented rather than in a narrow strip, which is the case in the recent beach nourishment project,” it emphasized.

“Collaborative action among institutions and stakeholders is needed to ensure that efforts to rehabilitate Manila bay will benefit both the environment and the society,” the group added.