Disentangling the effects of climatic variability and climate extremes on the belowground biomass of C3- and C4-dominated grasslands across five ecoregions

Elucidating the variation in grassland belowground biomass (BGB) and its response to changes climatic variables are key issues plant ecology research. In this study, BGB data for five ecoregions (cold steppe, temperate dry savanna, humid temperate) were used examine effects of variability extremes on C3- C4-dominated grasslands. Results showed that varied significantly across ecoregions, with highest levels cold steppe lowest savanna. The results indicated growing-season temperature, maximum minimum temperatures their interactions had positive single-harvest C3 plants colder (i.e., steppe) C4 arid savanna). savanna ecoregion declined increasing temperature during growing season. Growing-season precipitation exerted significant ecoregions. Annual negatively impacted annual ecoregion, because dominance plants. Increasing cumulative elevated mean reduced both categories Compared normal climates, extreme events season enhanced tended increase wet decrease moderate compared climates. This study suggests differential can be explained by differences types, These findings responses constitute important scientific evidence emphasizing need maintain ecosystem stability