Life-stage dependent response of the epiphytic lichen Lobaria pulmonaria to climate

Abstract

Lichens are poikilohydric organisms, whose internal water content tends to reflect external humidity conditions. After drying, they can reactivate their metabolic activity through water vapor uptake or liquid water input. Thus, lichen water-related functional traits are important as they are involved in the duration of the hydrated period. Models predicting the effect of environmental conditions on lichens are based mainly on the presence or absence of adult thalli. Nevertheless, ecological conditions required by lichens might vary during their life cycle, for example during propagule establishment or in the first stages of thallus development. Little is known about the different ecological requirements at the different development stages in lichens. In this work, we measured water holding capacity (WHC) and specific thallus mass (STM) of adult and juvenile thalli of the model species Lobaria pulmonaria along a climatic gradient to constrain the process-based model LiBry. The LiBry model allows accounting for the productivity of lichens with different physiological strategies under various environmental conditions. We simulated the activity and performance of adult and juvenile thalli in 9 regions of Italy and Corsica. The model was used to test if adult thalli of L. pulmonaria have a higher survival probability due to their higher aerodynamic resistance. In the current climatic condition, the LiBry model predicts a higher survival probability of adults with decreasing absolute survival rates of both life stages with increasing temperature. Adult thalli also result in having higher active time, STM, and relative growth rate (RGR). We discuss the main implications of our simulation outputs, provide future perspectives and possible implementations of the LiBry model.

Quantifying the effect of competition on the functional assembly of bryophyte and lichen communities: A process‐based model analysis

“…This may provide a potential explanation for the modelling result that no or weak competitive exclusion best explains observed trait distributions. While facilitative interactions are not explicitly included in the model, some positive community‐level effects are represented by parameterized ecophysiological relations of the strategies, such as the decreasing effect of height on evaporation (Di Nuzzo et al., 2022), which only becomes effective when growing in a cushion. Several studies have found that facilitation arises frequently between associated lichens and bryophytes (Colesie et al., 2012), and when interacting species acquire resources in complementary ways (Bowker et al., 2010).…”

The impact of climate aridification on rare lichen communities

“…and Nikolić et al (2024) present methodologies for predicting climate change impacts on lichens, offering a framework for future research in "Burabay" and beyond. Ås Hovind et al (2020) and DiNuzzo et al (2022) explored lifestage dependent responses to climate, which could inform management strategies for preserving lichen diversity in changing climates. Studies byMunzi et al (2019) andYang et al (2023) on the physiological responses of lichens to drying periods provide a mechanistic understanding of how aridification affects lichen biology, complementing our observations of community-level changes.…”