CLIMATE CHANGE EFFECTS ON MACROFUNGAL COMMUNITIES IN TROPICAL, TEMPERATE AND MONTANE HABITATS: A SYSTEMATIC REVIEW AND BIOME-COMPARATIVE SYNTHESIS SYED ABRAR* AND ROMANA MIRDHE

Climate change is increasingly reshaping terrestrial ecosystems through rising temperatures, altered precipitation regimes and intensifying climatic extremes, yet fungal responses—particularly those of macrofungal communities—remain comparatively underrepresented in global change syntheses. This systematic review evaluates how climate change influences macrofungal phenology, productivity, community composition and spatial distribution across tropical, temperate and montane habitats, and identifies the mechanisms driving biome-specific responses. Following PRISMA 2020 guidelines, we synthesized peer-reviewed evidence from long-term observational records, elevational gradients, manipulative experiments and modeling studies that explicitly link macrofungal dynamics to climatic drivers. Across biomes, macrofungal responses are mediated by recurrent mechanisms involving temperature thresholds, moisture availability, substrate dynamics and host-mediated carbon allocation. Temperate systems exhibit the clearest climate signals, with multi-decadal datasets documenting delayed autumn fruiting, extended fruiting seasons and shifts in guild composition under warming and changing precipitation regimes. In tropical ecosystems, where temperature limitation is minimal, rainfall seasonality and dry-season intensity dominate macrofungal dynamics, producing strong interannual variability and pulsed fruiting responses that interact with land-use change and disturbance. Montane habitats show pronounced vulnerability, with widespread upslope shifts in fruiting elevation, climatic space compression and increasing risk of mismatch between trees and their ectomycorrhizal fungal partners. Functional guilds respond unevenly to climate forcing. Saprotrophic fungi are strongly regulated by moisture pulses and substrate availability, while ectomycorrhizal fungi respond indirectly through host physiology, carbon allocation and host redistribution under climate change. These differences complicate interpretation because fruit-body observations, belowground community composition and functional activity do not always respond synchronously. We conclude that macrofungal climate responses are biome-dependent, guild-specific and often mediated by indirect pathways. Integrating long-term sporocarp monitoring with molecular approaches, host distribution modeling and hydroclimate metrics is essential for predicting ecosystem-level consequences. Expanding standardized long-term monitoring in tropical and montane regions remains a critical research priority.