Ecological consequences of fires
The specific threat posed by forest fires is a result of the fact that Polish forests are one of the most flammable in Central Europe. That is the result of, among others, a high percentage of old coniferous foreststands and the domination of pine in the species composition.
The most flammable are the forests aged up to 40 years which make up almost 29% of the forest area of the State Forests.
Material loss is a result of fires, yet incomparably harder are biocenotic losses, which are approximately five times larger than material losses
Fires are a significant threat to the Natura 2000 areas. 20,5% of the State Forests area (1,5 million hectares) are areas of special bird protection, about 13,2% (ca.1 million ha) are special habitat protection areas.
Forest fires cause also a decrease in biodiversity. A direct effect of fires is a total or partial damage of plants, death of soil organisms, animals as well as damage of habitats of many species (including rare and protected species).
One hectare of forest area in the most intense growth period absorbs up to 120 tons of carbon. These forest stands (aged 5-10 years) burn most often. What is more, large amounts of carbon dioxide are excreted during fires (respectively 82 tons per hectare during fires of soil cover and below the surface and 94 tons per hectare during total fires).
During fires carbon monoxide, solid or liquid particles (smokes), hydrocarbons and nitrogen oxides are released.
In times of global climate changes the unfavourable role of this impact caused by fires is indeed crucial.
The weakened trees become easily infected by harmful insects or parasitic fungi. As a consequence, the trees decline and the reproduction of parasites may threaten the surrounding forests.
A subsidiary negative effect of forest fires are abiotic changes of the ecosystems including changes of the microclimate and soil.