Autecological studies on Audouinia capitata. 8. Fire

Autecological studies on Audouinia capitata (Bruniaceae). 8. Role of fire in regeneration
J.H.de Lange & C.Boucher 1993 South African Journal of Botany 59 188-202 https://doi.org/10.1016/S0254-6299(16)30752-9

In A. capitata the protracted juvenile phase, the longevity of plants and their effective vegetative fire regeneration, are all possibly adaptively linked to poor sexual reproduction. After a fire-free period of more than ten years, averages of only 4.7 and 0.4 seedlings per plant were recruited following summer and winter burns, respectively. The positive correlation between the prevalence of fynbos fires from January to March and the germination response of soil-borne seeds when treated with smoke at different times of the year, suggest that the species has evolved in a fire-prone vegetation in a climate with a seasonal rainfall distribution similar to the present one. The vegetative vigour of shoots, the size and numbers of inflorescences, and seed set were increased by fire. The continuation of a policy of late autumn and winter burns may be fatal for survival of the species. Plants responded favourably to fire at a post-fire age of 11 years. Some populations, however, were still vigorous and sexually productive at a post-fire age of 20 years.
&

"A. capitata seedlings are recruited in the same or the following season and only after fire. A total of 110 seedlings were found in three populations (Sirkelsvlei North, Bonteberg East and Klaasjagers Plateau) at the commencement of the present A. capitata project in July 1987, 17 months following an extensive fire in the Cape of Good Hope Nature Reserve on 1 February 1986. The environment at the Teeberg population is strewn with loose rocks and the quick post-fire regrowth of the vegetation precluded a reliable survey for seedlings here. In populations burnt in the same fire, but discovered later, an additional 38 seedlings were recorded. A number of dead seedlings were observed.
The controlled bum in the Sirkelsvlei West population (21 February 1989) .. for the first four months following emergence showed no signs of predation despite the small size of the burnt area. Prior to the bum, 45 flowering plants were marked and mapped. At the end of September, seven months after the fire, a total of 334 seedlings had been recorded, all of them in close proximity to the parent plants"

more? see the paper.

Publicado el junio 16, 2022 08:22 TARDE por tonyrebelo