Influence of a low-intensity fire on a Pinus halepensis Mill. forest seed bank and its consequences on the early stages of plant succession

Abstract

The effect of an experimental low-intensity fire on the soil seed bank and its consequences on the early stages of post-disturbance succession were analyzed. The hypothesis that low-intensity fire may produce a population decline of hard-seeded species by the elimination of established plants and the lack of a seed germination promotion effect was investigated. Consecutive pre- and post-burning soil samplings revealed extremely low impact of fire on seed banks. In contrast, some specific seed banks increased with fire, probably due to a seed rain from fire-opening of capsule fruits. Fire neither promoted germination of hard-coated seeds nor affected their viability. Both the length of the seed-unproductive juvenile phase and post-fire habitat conditions were revealed as critical in determining the recovery of hard-seeded species after a low-intensity fire. Species with a short life cycle produced seeds in the year subsequent to the disturbance, ensuring a progressive moderate recovery from the few individ...