One of the reasons that a very small budget has been allocated to the ENR department of the Philippines as identified above could be that the investments made in trying to protect the environment show a very slow rate of return. Benefits of the investment are long term and unlike other investments that seem to show a rate of return almost immediately, the fact that the benefits are not seen as quickly may deter them from allocating a more substantial budget to the ENR department.
Also, it might be that though the environmental crisis is an exorbitant problem in the Philippines, the effects of this problem are not as easy to imagine in vivid imagery as are instances of death arising from more dramatic and sensational events such as car accidents. This is known as the availability heuristic. Effects of global warming and ozone layer depletion are not easy to imagine, and people might undermine the seriousness of this problem, though it may require immediate and prolonged attention and effort.
Image Source: Stephdress
Another possible factor can be accounted for by the prisoner-of-experience principle. Humans have trouble conceptualizing hazards that they have not personally experienced. No one has of yet experienced the catastrophic threats of complete deforestation or biodiversity loss, and the possibility of this situation may seem to the people of Philippines to be almost out of the realm of possibilities. As such, the problems of biodiversity loss may seem difficult to take seriously, and the people and government authorities may tend to underrate, ignore or deny them.