Regional features of the formation of pyrological environments in the steppes of Northern Eurasia based on Firms data

Abstract

Grass fires are characteristic of the vast region of Northern Eurasia, covering the landscapes of the steppes and adjacent natural areas. The study of the spatio-temporal heterogeneity of fires makes it possible to identify and evaluate the leading factors of the occurrence and spread of fires. Pyrological research is of particular relevance due to the negative impact on various groups of steppe biota and the quality of the environment, the lack of an objective understanding of the causes of the high variability of fire development indicators. The main objective of the study was to identify regional features of the formation of pyrologic environments in the long-term and intraannual aspects. The global archive of thermal anomalies MCD14ML (FIRMS) was adopted as the main source of fire data and the analyzed parameter itself. It is revealed that a specific feature of the FIRMS data archive is the possibility of fixing active fires on arable land, which is almost impossible to carry out directly from satellite images. In this regard, the greatest density of thermal anomalies is observed in the agriculturally developed provinces (western sectors of the steppes and adjacent territories), for which the practice of agricultural bollards remains a traditional way of farming. A comparison of the long-term dynamics of fires in arable land and pasture-hayfields shows a close relationship. Similar results were obtained during the analysis of the intra-annual (daily) distribution of thermal anomalies, the peaks of which occur at the beginning and the period of completion of agricultural work. This serves as indirect evidence that uncontrolled agricultural fires are the cause of a significant part of steppe fires. Regional pyrological conditions in the steppes of Northern Eurasia and adjacent territories have similar features in long-term dynamics and reflect the complex nature of the interaction between natural and anthropogenic factors. Understanding current trends in the development of fires can contribute to solving the problems of managing fire-hazardous situations.