Temporal beta diversity and plant metacommunity structure dynamics over a 43-year period in an inter-tropical mexican arid region

Understanding the dynamics of metacommunity structure and temporal beta diversity is vital for comprehending ecological dynamics at local and regional scales; it is essential to evaluate impacts of factors such as climate change, dispersal, and biotic interactions. We examined changes in the composition and abundance of 199 perennial plant species in the semiarid Zapotitlán Valley, Mexico, over a 43-year period. We studied three local community types, scrubland, cardonal, and tetechera, with surveys conducted in 1980, 2003, 2018, and 2023. Shifts in species composition and abundance over time were analysed using the Temporal Beta Diversity Index distinguishing between species gains or losses. We investigated the metacommunity structure elements—coherence, turnover, and boundary clumping—in each survey. We observed pronounced temporal changes in species’ composition and abundance across all community types. These temporal changes stem from the losses and gains in species and individuals. Notably, 2023 showed significant losses in species occurrence and abundance, potentially attributable to an extended drought likely exacerbated by climate change. Surprisingly, the metacommunity structure remained Clementsian throughout our study, emphasising the stability of the cardonal in maintaining distinctions between local community types. This suggests that the metacommunity spatial structure is resistant to changes in local community compositions.