Natural and anthropogenic fire regimes in boreal landscapes of Northwest Russia

Abstract

Patterns in the natural fire regime in different types of geographical landscape and its present-day transformations are considered. Surveys were carried out in the north-west of the Russian boreal zone at the junction of two North-European physiographic domains – Fennoscandian Shield (Fennoscandia) and East-European (Russian) Plain. The resultant data disclose the history of fires and their landscape-related characteristics over the past millennium. The frequency and intensity of wildlife fires may differ drastically among landscapes – from 1-2 in a century to 1-2 in a millennium. Multiple intermediate variants fill the range between these two poles. It is demonstrated that conservation of pristine forests with their spontaneous dynamics in protected areas is possible only under a natural fire regime. The total and average size of fires has been gradually decreasing. In the study area, e.g. the indices have over the past half a century ranged within 100-10 000 ha, and 5-20 ha a year, respectively. Humans have significantly increased the frequency of forest fires. The patterns identified can be quite confidently extrapolated to the whole boreal zone of European Russia. The characteristics of geographical landscapes (the range, ratio and spatial arrangement of their types) and land use history must however be taken into account.