How a Short Prescribed Fire Affects Soil Physical and Hydraulic Properties, Soil Water Balance, and Emergent Vegetation in a Grassland

A controlled burn was conducted on a grassland in Řisuty, Czech Republic, to study the effects of a short prescribed fire on soil physical and hydraulic properties, soil water balance and emergent vegetation. The grassland was newly established on arable soil three years prior to the study. The experimental site contained a weather station and sensors to measure soil temperature and soil moisture at three different depths. The soil, a loamy Cambisol, was not water repellent. A 5 x 5 m plot covered with sun-dried grass was burnt. The fire reached a temperature of about 700 °C over a period of 15 minutes. The subsequent hydrological regime of the soil was compared with that of a nearby unburned reference plot. Immediately after the fire and at weekly to monthly intervals thereafter, soil samples were taken to determine organic carbon content, soil structure stability, hydraulic conductivity, bulk density and soil texture. The results showed that temporary burning improved the hydraulic properties of the topsoil, with the infiltration capacity and water content of the soil in the burnt plot increasing throughout the year compared to the control plot. This provided a suitable habitat for the colonising vegetation. The findings suggest that small-scale controlled biomass burning can have a positive impact on the soil ecosystem and a temporary improvement in the hydraulic properties of the upper soil layer. The contribution is a result of a INTER‐COST project of the Ministry of Education, Youth and Sports of the Czech republic, grant no. LTC20001.