Forest fires and their impact on biodiversity

A recent case:

For months, several forest fires have occurred in different localities of the national territory, the most mentioned being the one registered for more than a week in Valle Nuevo, which was even compared to the forest fire that occurred in the same place in 1984 where they burned some 2000 land areas and that today, 39 years later, has not fully recovered.

On this occasion, the fire turned immense carpets of pine, juniper and palo de cruz (Podocarpus) into ashes, which are three species of conifers, endemic or unique in the world, which is why the damage to biodiversity is immeasurable.

The life of the Sabana Yegua depends on the burned area, the flourishing agriculture in Plena de Azua, which not long ago was a true desert, the Jigüey, Aguacate and even Valdesia and Las Barías dams, where the water comes from to the capital.

Who causes forest fires?

According to the National Fire Management Strategy of the Ministry of the Environment and Natural Resources, the majority of forest fires in the Dominican Republic are of anthropogenic origin, either intentionally generated to expand production areas or due to negligence in the use of fire, especially in agricultural burning. Among the main causes of occurrence of forest fires the mainly identified are:

  • Conuquismo (work to prepare the land for agriculture)
  • Livestock (to renew and settle grass)
  • Arsonists in conflicts (people dissatisfied with administrative measures or personal vendettas)
  • Accidentals falling of electrical cables, welders, etc.)
  • Forest users (hunters, beekeepers, fishermen, woodcutters, charcoal burners, ecotourists, night walkers)
  • Electric shocks

Only 2% of forest fires are produced by natural causes, such as electrical shocks.

Either way, fires are one of the main factors in the loss of biodiversity in rainforest ecosystems. After a fire, the affected territory can take 15 to 30 years to recover the lost forest cover.

What are the damages?

  • Fires can be followed by the colonization and infestation of insects that disturb the ecological balance.
  • Burnt endemic species.
  • They are a major source of carbon emissions, contributing to global warming that could modify biodiversity.
  • They modify the volume of biomass, alter the hydrological cycle with consequences on marine systems such as coral reefs, and influence the behavior of plant and animal species.
  • Smoke from fires can markedly reduce photosynthetic activity (Davies and Unam, 1999) and adversely affect the health of humans and animals.
  • It is more likely to occur in subsequent years as trees fall, allowing sunlight to dry out the forest and cause an accumulation of fuel with an increase in fire-susceptible species, such as flammable herbs.
  • The consequence of repeated fires is detrimental because it is one of the main factors in the loss of biodiversity in rainforest ecosystems.
  • Human-induced fires have contributed to drastic declines in the populations of 60 vascular plant species, ten fungal species, eight lichen species, and six moss species over the past two to three decades (Shvidenko and Goldammer, 2001).

In forests where fire is not a mechanism of natural alteration, it can have devastating effects on forest species, vertebrates and invertebrates, such as the loss of habitats, territories, shelter and food. The disappearance of organisms of great importance for forest ecosystems, such as invertebrates, pollinators and decomposers, can significantly delay the rate of forest recovery (Boer, 1989).

The fires cause the displacement of birds and mammals, which can alter the local balance and ultimately cause the loss of wildlife, since the displaced individuals have nowhere to go. For example, the devastating fires of 1998 in the Russian Federation caused increased water temperatures and elevated carbon dioxide levels in lakes and streams, which negatively affected salmon spawning (Shvidenko and Goldammer, 2001).

In burned forests populations of small mammals, birds and reptiles are reduced and also carnivores tend to avoid burned areas. The declining densities of small mammals such as rodents may negatively influence the food supply of small carnivores.

Fires also destroy leaf litter and the arthropod communities that inhabit it, further limiting food availability for omnivorous and carnivorous species (Kinnaird and O’Brien, 1998).