Do local environmental conditions affect intraspecific trait variance? Insights from liverwort populations in ecological refuges

Abstract

Understanding trait variation along environmental gradients is crucial for assessing the adaptive potential of species. We analysed the intraspecific variation in six morphological traits of Frullania ericoides across environmental gradients (elevation, canopy openness and distance to water sources) in a humid ecological refuge in Brazil’s semi-arid region. The traits measured (mean and coefficient of variation) were: leaf lobe area, leaf lobule area, underleaf area, stem width, ratio between leaf lobule area and leaf lobe area, and ratio between the number of laminate lobules and the total number of lobules. Seventy specimens from eleven localities (populations) showed greater intrapopulation than interpopulation mean trait variation. All traits, except for the ratio between leaf lobule area and leaf lobe area, presented interpopulation differences. Two trait strategies emerged: one related to water storage and plant size, and the other linked to proportional increases in leaf lobule area and lobe area. The lower the elevation was, the higher were the mean values of leaf lobe area and leaf lobule area, and the variance of stem width. The species exhibited significant trait variation, which can be decisive in the responses of populations to new selective pressures of establishment and maintenance.