Post-fire changes in plant growth form composition in Andean páramo grassland

Abstract

Questions 14Fire suppression policies have been widely adopted in the páramo grasslands of the northern 15Andes to protect their biodiversity and ecosystem services. Páramos have been regularly 16 burned for many years, and it is not clear how páramo vegetation will respond to significant 17 changes in their fire regimes. This study investigates differences in plant growth form 18 composition, light levels and soil temperatures in páramo plots representing a range of 19 recovery times since the last fire. 20 Location 21Reserva Ecológica El Ángel and La Bretaña Nature Reserve, Carchi, Northern Ecuador. 22 Methods 23We assessed the frequency of ten páramo growth forms, vegetation height, soil temperature, 24 and light intensity in fifteen fire sites with historical records of fire (<1 -15 years since fire), and 25 one recently unburned site (at least 40 years since fire). A chronosquence of sites was used to 26 assess potential changes in plant community composition in post-fire succession of páramo. 27 Results 28The recovery of páramo vegetation after fire comprised three phases: initial recruitment with 29 high growth form diversity, followed by reduced diversity, light and soil temperatures in dense 30 tussock vegetation, and ultimately canopy height stratification with a return of diversity. All but 31 one plant growth forms were represented in each of the three phases, and the changes 32 reflected differences in relative abundance. 33 Conclusions 34Post-fire páramo succession is characterized by clear shifts in the relative abundance of plant 35 growth forms, ending with (co-)dominance of upright shrubs. The long-term consequences of 36 such shifts for biodiversity and ecosystem function, given the widespread adoption of fire 37 suppression policies in the páramo need careful, evidence-based consideration. 38

Analysis of the vascular flora in the Cajas National Park (Central Andes, Ecuador)

“…The vegetation of the CNP has a high diversity of biological types; of the ten main categories proposed by Rivas-Martínez (2004, 2007 only the pleustophytes are missing. This richness of adaptive types was reported by Zomer & Ramsay (2020), with significant differences between localities (Ramsay & Oxley, 1997).…”

Physiognomic responses of páramo tussock grass to time since fire in northern Ecuador

“…A study of tussock grass responses to time since fire in an Australian grassland found that tussocks senesced by 11 y after fire, and subsequent fires did not immediately return the tussocks to a more vigorous state, leading the authors to conclude that ≤5 y fire intervals were necessary to maintain tussock dominance (Morgan & Lunt 1999). While our study did not indicate a canopy "collapse", Zomer and Ramsay (2020b) concluded that the dense tussock canopy might open up in a later succession phase.…”

Plant Diversity and Composition Changes along an Altitudinal Gradient in the Isolated Volcano Sumaco in the Ecuadorian Amazon

“…Abundance scores were established according to the Braun Blanquet scale (1, <5%; 2, 6-25%; 3, 26-50%; 4, 51-75%; 5, >75%); the symbols-'r' and '+' were not used, due to the small size [9]. Then each species was classified according to its lifeform as: cushion, erect shrub, erect herb, prostrate herb, tussocks, acaulescent rosette, basal rosette or stem rosette [62][63][64]. The frequency of each of the life-forms described above was evaluated.…”