A negative impact of global climate change and excessive human anthropogenic load are accompanied by the frequent occurrence of forest fires, especially in pine forests, which are the most fire hazardous. The study attempts to analyze the forest plantation fires in the Boyarka Forestry Research Station, Kiev region, over a 13-year period (2004–2016) by the number and area of forest fires.
The purpose of the study was to examine the distribution of forest fires by years, forest areas, months of forest fire season, days of the week, hours of the day and their association with types of forest conditions over a 13-year period according to data on Boyarka Forestry Research Station.
Materials and methods
The study of forest fire danger was carried out according to the methods developed by Dusha-Gudym and Safronov. We used forest fire data recorded in the pine stands of Boyarske, Plesetske and Dzvinkivske forestries of the Boyarka Forestry Research Station.
According to the statistics of the Boyarka Forestry Research Station, there were 762 fires during the past 13 years. Fire maximums were detected in 2009 (176 fires in the total area of 63.4 hectares) and in 2015 (128 fires in the total area of 21.1 hectares). The greatest number of fires (664) and largest area (253.2 hectares) were in the forests of the Boyarske forestry, which is explained by the proximity of these forests to Kyiv city. In two other forestries, the number of forest fires was almost 7 times less, while the average area of one forest fire in these forest areas was significantly higher. Thus, the average area of a forest fire was 1.06 ha in the Dzvinkivske forestry against 0.38 ha in the Boyarske forestry.
The number of forest fire accidents did not directly depend on the air temperature. As an example, the number and area of forest fires were even higher in April than in May in the Boyarka Forestry Research Station in general. This is due to the fact that in April, after snow cover melting, the last year's ground vegetation, fallen leaves and needles dry up and are flammable. However, the increase in the number and area of fires in August relates to high temperatures, that is, to a high class of forest fire danger according to weather conditions.
The largest number of forest fires was registered on Monday (21.4 %). This can be explained with the fact that the fires were found out on weekends and completely neutralized only on Monday. At the same time, the greatest number of forest fires by the time of day was detected, between 14 and 16 hours, when there were a lot of tourists in the forest.
Comparison of the stands growing in different types of forest conditions showed that most often, forest fires occur in the forest stands growing in fresh and moist fairly poor soil conditions. In moist fairly fertile oak site conditions, the number and area of forest fires were much less, due to the presence of hardwood species in the composition, risk of fire for which is considerably lower. The greatest number and area of forest fires were recorded in the middle-aged stands, which are the most widespread among the pine forests of the Boyarka Forestry Research Station. It was found that 39.9 % of forest fires had in an area of up to 0.1 hectares and 35.6% an area of up to 0.5 hectares.
In Boyarka Forestry Research Station, the fire maximums were detected in abnormally dry years, 2009 and 2015. The most fire-dangerous stands grow in Boyarka forestry, which is the closest to Kyiv city. Based on the number of forest fires, the relative forest fire danger for Boyarske and Plesetske forestry was assessed as “extreme”, for Dzvinkivske forestry as “high”. By the fire area, the fire danger was assessed as “high” for Boyarske forestry, as “medium” for Plesetske forestry and as “lower medium” for Dzvinkivske forestry. The greatest number of fires was recorded in April and in August.
During the year of fire maximum, it is necessary to strengthen the forces and fire-fighting equipment and also to improve roads and access ways for the elimination of fires. Special attention should be paid to the pine stands, which grow in fairly poor soil conditions, where the greatest number of fires occurs.
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