The response of the moss Campylopus lamellatus (Leucobryaceae Schimp.) post El Niño: a case study in the Caatinga

Abstract

Biological soil crusts (biocrusts) are important biological components in arid and semi-arid regions because they can serve as ecological facilitators for the vascular flora. Biocrusts of rocky outcrops of the Caatinga biome in the semiarid region of Northeast Brazil are comprised mainly of populations of the pioneer moss Campylopus lamellatus. Meanwhile, the Caatinga is undergoing progressive desertification, which is likely to continue for the next 100 years. Therefore, the physiological responses of C. lamellatus to climate change should be included in predictions regarding the future of the flora of these rocky environments. We evaluated a population of C. lamellatus during a prolonged drought brought about by El Niño, and during the first subsequent rainy season. We used biomass (dry mass) and proportion of chlorophyll as measures of tolerance. We identified decreased investment in biomass allocation and the degradation of photosynthetic pigments during the drought event. In contrast, we observed a rapid increase of chlorophyll during the rainy season, which represents biomass investment via chlorophyll regeneration. We conclude that the resilience of C. lamellatus is rapid, even for a photophilic plant, and should ensure its facilitative function under conditions of water saturation of the environment.

A comparative study of temporal variation of two epiphytic bryophytes in a central Amazonian white-sand forest, Brazil

“…In the following rainy season, they observed a positive investment in biomass and photosynthetic recovery in the same moss species. The recovery in colony density observed here and the physiological recovery observed by Silva et al (2020), points that bryophytes might be able to recover after a drought event, as long as favorable environmental conditions proceed such drought events.…”

“…An study with the moss species Campylopus lamellatus during the El Niño of 2015-2016, also showed a negative response to the prolonged drought event in that year (Silva et al 2020). In the following rainy season, they observed a positive investment in biomass and photosynthetic recovery in the same moss species.…”