ПОЖЕЖНІ ПРОЯВИ В ЦІЛИННО-ЗАЛИШКОВИХ ДІЛЯНКАХ ПІВДЕННОГО СТЕПУ В МЕЖАХ МИКОЛАЇВСЬКОЇ ОБЛАСТІ ТА ЇХ ОСОБЛИВОСТІ

Abstract

The article reflects the results of the first stage of monitoring studies of the impact of fires on the state of locally small areas of the Southern Steppe, existing as part of the mosaic agricultural landscape of the Mykolaiv region. The spatial-temporal and seasonal specifics of the manifestation of steppe fires have been established, the main patterns and causes of occurrence have been clarified. The main background condition for conditionally spontaneous fires in steppe biotopes is the presence of a layer of vegetative-detritus sediment and a uniform wind flow with speeds from 12 to 17 km/h on the soil. Temporary and less fast wind currents are not able to move the front of a fire that tends to self-extinguish for a long time. Also, excessively powerful winds with pronounced gusts (20-28 km/h) in most cases lead to the over-ground spread of fire and its attenuation in areas of absence of tall dry vegetation. The seasonality of the manifestation of steppe fires consistently demonstrates two peaks - early spring and late summer. Summer-autumn fire manifestations in the steppes are more frequent, but they are localized due to the mosaic nature of the modern agricultural landscape and mainly secondary development from primary ignition sites. The main reason for the occurrence of the latter is the burning of stubble, ignition of roadside strips of vegetation and burning on the rural outskirts, from which the fire spreads to neighboring areas of steppe vegetation. The main causes of steppe fires during the research period (1994- 2024) show certain dynamic changes due to a decrease in the area of hayfields and pasture exploitation and the normalization of the timing of the implementation of agrotechnical measures in field biotopes