Shifting Sands: A Meta-Analysis of Climate Change Impacts on the Distribution and Phenology of Key Woody Plant Species in the Kalahari Ecosystem, Botswana (2020-2024)

This study encompasses a meta-analysis of surveys conducted from January 2020 to December 2024 focused on the effects of climate change on the distribution and phenology of the most dominant woody species in the Kalahari ecosystem of Botswana. The anticipation of these challenges is the basis of the conservation and adaptive management. The meta-analysis to the 35 studies included in the research confirms the presence of a significant trend in range shifts toward the poles and uplands for some dominant woody species (weighted average effect size d = 0.42, p < 0.001), indicating a reduced extent of favorable habitat at lower latitudes and elevations. The most pronounced changes in flowering and leafing phenology were more than two standard deviations and were accelerating at a rate above the long- term trend (weighted average effect size: d =-0.31, p<0.001). This indicates shifts in the functioning of ecosystems and plant-pollinator dynamics. In particular, meta-regression analysis revealed range shifts were predicted by the degree of seasonality in rainfall, where species in regions with more pronounced dry season pairs showed greater shifts (dry β =-0.15; p<0.01). Does the same hold for the species that perform poorer during dry spells and are known to develop shallower roots? These are the species that showed a greater rate of advance in leafing phenology (β=-0.12; p<0.01), and that is perhaps because of their greater sensitivity to soil moisture changes.