A major effect of climate change on land is evident. Typhoon Lando showed how destructive a typhoon can be on people and land resources.
But fewer people are aware that typhoons also destroy shallow coastal and marine resources as well as resources in the deeper parts of oceans.
During the past few years, we have seen how coral reefs and their associated fisheries were decimated by typhoons.
The affected coral reefs will take decades to recover — if ever they will recover at all. This is true of several reefs situated in eastern parts of islands.
As coral reefs are usually situated on shallow areas down to 40 or 50 meters, we must protect as many reefs on the western sides of islands, including those occurring in deeper waters, to maintain present fishery yields.
Local government units, the Department of Environment & Natural Resources and the Bureau of Fisheries & Aquatic Resources, (including local communities) should make a concerted effort to protect these reef systems by declaring them as no-take reserves.
On the part of research agencies in the country, it is important that research effort be directed to deeper reefs to determine fish species and their abundance that find refuge in these reefs during typhoon events.
Such reefs should be recommended for strict protection. Let us not wait until reduction of fishery yields from reefs becomes evident before taking any action.
I am reminded of a recent television interview of a governor of a province in Central Luzon who said that the destructive floods from waters in the Pampanga and Bulacan rivers due to Typhoon Lando was caused by forest denudation through logging in Nueva Ecija.
If so, why did local and national governments fail to foresee the consequences of the forest destruction? What should government do now to prevent repetition of these destructive floods, which are expected to occur again?
Moving to oceanic waters, climate change in terms of warming of oceans can certainly affect fishery yields.
In these waters, the primary producers are the plant plankton which are exposed to sunlight under conditions of availability of nutrients for photosynthesis.
The upper layers of oceans, such as the West Philippine Sea, are heavily dependent on nutrients coming from the bottom of the ocean through upwelling events.
Such events can happen only under favourable conditions when there is a reduction (or absence) of the thermocline layer, which blocks the connectivity of the upper and the lower layers of water.
During summer, this thermocline is thick (150-200 meters) but during winter months, it becomes thinner (or it disappears).
Other processes such as wind action can help in the mixing of the upper and lower layers of ocean water, facilitating photosynthesis.
High water temperatures during the summer months tend to thicken the upper layers, and prevent mixing with lower cooler layers and therefore, limiting phytoplankton growth and reproduction in the upper layer.
Since oceanic fisheries depend primarily on plankton, fisheries production will be limited under conditions of high temperatures.
Furthermore, as explained earlier, reclamations in the atolls in the West Philippine Sea makes the environment difficult for fish, and their larvae to survive, and be transported by prevailing ocean currents, and therefore, tend to decrease fishery production in the long term.
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Author’s email: suakcrem@yahoo.com
