Morphological and biochemical responses ofSphagnummosses to environmental changes

Abstract

Abstract•Background and AimsSphagnummosses are vital for peatland carbon (C) sequestration, although vulnerable to environmental changes. For averting environmental stresses such as hydrological changes,Sphagnummosses developed an array of morphological and anatomical peculiarities maximizing their water holding capacity. They also produce plethora of biochemicals that could prevent stresses-induced cell-damages but these chemicals remain poorly studied. We aimed to study how various anatomical, metabolites, and antioxidant enzymes vary according toSphagnumtaxonomy, phylogeny and environmental conditions.•MethodsWe conducted our study in fiveSphagnum-dominated peatlands distributed along a latitudinal gradient in Europe, representing a range of local environmental and climate conditions. We examined the direct and indirect effects of latitudinal changes in climate and vegetation species turnover onSphagnumanatomical (cellular and morphological characteristics) and biochemical (spectroscopical identification of primary and specialized metabolites, pigments and enzymatic activities) traits.•Key resultsWe show thatSphagnumtraits were not driven by phylogeny, suggesting that taxonomy and/or environmental conditions prevail on phylogeny in drivingSphagnumtraits variability. We found that moisture conditions were important determinants ofSphagnumanatomical traits, especially those related to water holding capacity. However, the species with the highest water holding capacity also exhibited the highest antioxidant capacity, as showed by the high flavonoid and enzymatic activities in their tissues. Our study further highlighted the importance of vascular plants in drivingSphagnumbiochemical traits. More particularly, we found thatSphagnummosses raises the production of specific compounds such as tannins and polyphenols known to reduce vascular plant capacity when herbaceous cover increases.•ConclusionsOur findings show thatSphagnumanatomical and biochemical traits underpinSphagnumniche differentiation through their role in specialization towards biotic stressors, such as plant competitors, and abiotic stressors, such as hydrological changes, which are important factors governingSphagnumgrowth.