Post-fire effects on bryophytes in High-Altitude Fields

Abstract

High-Altitude Fields are ecosystems with high bryophyte abundances and diversities. One of the principal threats to these ecosystems are wildfires, which mainly affect terricolous species. Chronosequence studies can aid in understanding post-fire effects on bryophytes. We studied terricolous assemblages of bryophytes in the High-Altitude Fields of Itatiaia National Park (INP) by establishing three 20x1 m transects in five areas: three areas of a post-fire chronosequence (treatments 2017, 2007, and 2001) and two control areas. We analyzed the species richness, floristic composition, life-forms, and floristic similarities of those transects, identifying 27 species of mosses (18 genera; 11 families) and 26 species of liverworts (20 genera; 16 families). Ditrichaceae was the principal moss family and Cephaloziellaceae the principal liverwort family. The life-forms encountered were turf (43 %), weft (38 %), thalloid (10 %), and mat (9 %). Turf predominated among mosses (85 %), and weft among liverworts (62 %). Species richness and floristic compositions varied among the post-fire gradients. The grouping dendrogram and ordination diagram evidenced greater similarity among transects within the same area. However, there was no evident gradient of floristic composition along the post-fire gradient, and further studies will be needed to quantify environmental gradients and their influences on bryophyte composition.

Effects of Fire on Pyrodiversity of Terricolous Non-Tracheophytes Photoautotrophs in a Páramo of Southern Ecuador

“…These families have been previously reported in several studies as characteristic elements of the páramos of Ecuador [2,20,74] and other areas of tropical regions [75]. Therefore, the families noted above have been recorded as pioneers in areas under fire effects [27,62,65,71]. Although our results indicate the effect of fire on terricolous non-tracheophyte photoautotrophs (bryophytes and lichens), other variables such as páramo type, elevation, topography, and microclimatic factors, such as humidity and temperature, are limiting the diversity of these organisms [74]; therefore, these factors should be considered in future research.…”

“…In agreement with our results, Calabria et al [26] pointed out that the composition of terricolous cryptogam communities is influenced by fire. Similarly, Wienskoski and Santos [27] showed variations in species composition among treatments of areas that had suffered more recent fires. Following the same pattern, Pharo et al [71] mentioned that the species composition of terricolous cryptogams was strongly related to the severity of the fire, which was probably of low severity, as reported by Díaz et al [11], who used remote sensing methods in their study area.…”

“…Similarly, Orumaa et al [63] and Pharo et al [71] showed that the post-fire effect has positive consequences on the diversity and richness of terricolous cryptogams due to the increase in nutritional contents such as N, K, Ca, Mg, Fe, and Mn. Finally, Wienskoski and Santos [27] point out that the richness and diversity of terricolous cryptogams (e.g., bryophytes) are limited by the time after the fire, that is, the diversity is greater when the time after the fire increases.…”

“…For this reason, they are known as soil formers [21,22], have good water retention capacity [4], and are considered pioneer species in revegetation of degraded soil [23], increasing soil stability and water input rates that provide greater success in seedling establishment [24]. Therefore, previous studies in the páramos point out that the variables limiting lichen and bryophyte diversity are elevation, topography, microclimate, and edaphic properties [2,20,25], as well as some studies pointing out the effects of fire on diversity [26,27].…”

“…Along the same lines, studies applying the prescribed fire method to the diversity of bryophytes and lichens have been limited in temperate zones [26,42], and only in the Brazilian páramos Wienskoski and Santos [27] have shown the effects of natural fire on the richness and composition of bryophytes, but in South America, prescribed fire has not been applied. Therefore, the present research determined for the first time in Ecuador the effect of prescribed fire on the diversity of bryophyte and lichen communities in an herbaceous páramo in the southern region of Ecuador.…”