Soil pH, organic matter, potassium and phosphorous did not change, but soluble salt content increased significantly in the burnt sites.
Nitrogen as well as phosphorus losses via runoff were significantly higher at the 4 × burnt sites than at both the 1 × burnt and unburnt sites.
Soil N and P content were significantly higher in both burnt sites relatively to the control sites.
Unburnt and ground-burnt patches of short time-since-fire provided habitat for more species and had distinct assemblages from that of severely burnt sites.
Shannon diversity and the number of flowering shoots were higher, and the cover of the dominant grass Festuca pseudovina was lower in the burnt sites.
We compared six unburnt sites, two freshly burnt sites, eight sites which burned once at different times in the last 30 years, and seven sites where fires occurred repeatedly in the last 30 years.
Burnt sites with retention trees serve as pollinator source habitats and contain floral resources, highlighting the importance of natural disturbances and biological legacies in the conservation of pollination services from boreal forests.
LFH samples from burnt sites had a higher pH than from forests, but on average a lower abundance of individual snails (11 vs. 30 in 0.5 l LFH) and 50% lower species density (3 vs. 6 species).
Vegetation and litter cover played an important role in reducing runoff and the associated N and P transport at the 4 × burnt sites, since a decrease in both variables was observed with the increase in vegetation cover after fire.
